Transcript for:
Elementary Particles and Standard Model

[music] Elementary particles it's intuitively clear what this means something so very basic what can no longer be split into pieces cannot be find out what this particle consists of historically at the same time concepts changed probably the most elementary particles atoms were once considered because the ancient Greeks understood that people the world consists of some tiny things elements and such elements were considered Atoms But this continued until we couldn't get inside the atom Approximately 100 years ago rutherford bombardiers alpha particles thin foil discovered that the atoms are empty what is in the middle of the atom what was later called is found atomic nucleus which is approximately a thousand times smaller than the size of an atom and probably then one could say that elementary particle is atomic nuclei But besides atomic nuclei which have electric charge atoms have no charge should have been something else and that something else later got the name Electron So we have two elementary particles were obtained nucleus and Electron Well, that wasn't the end and pretty soon it became clear that the nuclei of different atoms are actually made of something else there are no single objects that can be consider elementary around the 30s of the last century Heisenberg in Germany and Ivanenko in Russia has put forward a hypothesis that the nuclei consist of two elementary particles protons and neutrons and we already have three elementary ones particles Proton Neutron and Electron for a long time this was the case but during this time quantum was born mechanics is a science that actually explained how the atom works Why Electron rotating in stationary orbits around the nucleus do not fall on this core in fact, according to the laws of classical Physics Electron as an electric charged particle should have been all the time emit light lose energy and very quickly fall on the core of this is not what is happening and the reason for this it turned out that Electron obeys the laws of quantum mechanics so here are three elementary particles Proton Neutron and Electron, it seems formed the whole world that we see in front of me, but naturally the question arose why don't they fly off to different places sides Why two Protons that have positive charge does not fly apart different sides under the influence of clones forces Why are they so closely connected with neutrons in the nucleus and another question If this is a particle Elementary if they are not made of anything consist and nothing can happen to them happen then Therefore they must live forever and not the throne as it turned out it disintegrates and quite quickly at that disintegrates into a proton, an electron and something still elusive this elusive thing was noticed by missing energy that is if measure the energy of the electron of the proton the energy of the original Neutron turned out to be some strange energy disappears somewhere Pauli suggested that these were new the elementary particle at that moment is it was completely revolutionary because it was thought that there were new elementary particles no longer, we already understand everything but it turned out not so field assumed that exists a small particle that does not carry electric charge has an extremely I suggested calling the small mass of the farm its neutrino so the number of elementary particles began to increase Proton Neutron electron and neutrino The neutron decayed into a proton, electron and nitrina Well, antinetrin actually but it's not that important now but it turned out that not everything should be was to tie protons and neutrons together And these are not electrical forces at all. because they are very weak Japanese physicist Yukawa suggested that there is another elementary particle which responsible for nuclear forces That is, for the forces that hold protons together neutrons inside the nucleus he suggested that there is another elementary particle nuclear force exists due to the exchange elementary particles of a new kind which in the latter subsequently were named pi-mesons greek letter pi so number elementary particles began gradually grow soon was also opened heavy electron consequences named myonom and physicists began to study space rays cosmic rays are radiation coming to us from space fly to us protons fly towards us electrons fly towards us antiparticles are flying and as it turns out, towards us some more strange objects are flying in in 1947 in Cosmic Rays was new elementary particle discovered which was called a camisole This particle had a number of strange properties properties in fact there were three misons One positive electric charge another negative electric charge and the third one turned out to be neutral, so here it is these three particles behaved in a somewhat strange manner and that's what it was called, oddity suggested that they possess some new property called strangeness and people became studying these strange particles turned out to be that the stone zones are not the only strange ones parts gradually the number of particles began increase in cosmic rays they fly to us Particles that can live a long time if they don't live long, they have time to fall apart before flying to us from space The question arises: How long do these live? Elementary particles what do we know about them to date Well, here's Electron How we are now seems to live forever we don't know what how can it fall apart the thing is that Electron is the most popular today light particle having an electric charge and therefore by virtue of the law of conservation energy is simply impossible for him disintegrate therefore today according to the idea Electron lives forever but generally speaking I could disintegrate but today we we know that his time of life measured experimentally exceeds 10 in 34 degrees of years but for comparison it is necessary say that the age of the universe is Proton lives for about 10 years, that is practically forever by these standards But here it does fall apart in the end though or does not disintegrate, this remains open question This is a question for an experiment which must determine whether it will fall apart or not the theory allows the proton fall apart Well, I already said that the proxitron lives. a fairly short time breaks down into Proton but inside nuclei or netron lives practically forever because it goes on and on back The process of converting a Proton into metro further kame-zone epimi zone which I am about said it turned out they live quite well short period of time type 10 minutes six seconds nine seconds then there is simply by human standards disintegrate instantly but by standards particle physicists they live quite a long time to it should also be added that they move at very high speed flying to us from space That is, from at a speed close to the speed of light and according to the general According to the special Einstein's theory of relativity time fast moving objects slow down so their own time flows very slowly it's practically worth it and therefore these particles Despite the fact that they seem to be at peace were supposed to disintegrate into elusive shares seconds actually live quite a bit long and manages to fly to us from space Well, cosmic rays are sources new particles new elementary particles they were once opened there and their number began to gradually increase and it became more and more further These particles began to be discovered on accelerators and in front of us formed a whole zoo of these particles particles of steel called by Greek letters appeared Roma Omega Zone bison are bison to seven zones sigma zones and so on and so forth furthermore and also other particles became so big that it will arise a natural desire to somehow classify like a table Mendeleev's periodic table as It is known that all elements have a very a good classification they fall into periods on rows and now thanks In quantum mechanics we understand how they arranged Why is there such a classification chemical elements chemical elements And here are the Elementary particles of them I would also like to do something about it classify As soon as there are so many of them many Well, naturally we need to look at properties of these particles how do they differ and try to somehow divide them into separate classes according to their properties one of such wonderful properties the presence of angular particles was found moment, that is, the particles represent from a classical point of view something similar to tops they spin very large angular momentum classical describe this angular momentum it would not work if the particles had some size had this angular the moment we measure is what happened what would be the surface of this particle rotates at a speed exceeding the speed of light what is impossible So classic describe this rotation not it works out that's why it's given to do only quantum mechanics But this one angular momentum as it turns out quantum mechanics it is quantized that is it acquires only whole or half-whole values In some units called with the Bor radio tape recorders, so it turned out that all particles can be divided into two class those with integer angular momentum and those who have half an integer angular momentum This particle has two different names particles with integer angular momentum are called bosons because when they gather in large numbers in a certain ensemble they obey statistics which is called the Boz statistic Einstein a particles with semi-integer angular At the moment they behave completely in other ways they obey completely other statistics this statistics has The name of the farm is Cancer and it turns out that that particles with the floor as a whole spinal from half-whole spinal This is completely two different classes of particles Well, if we talk about those particles that I already mentioned protons netrons electrons neutrinos this is all fermions, that is, particles with spin 1/2 But the pi-zones of the stone zones have spin 0 is flowerpots So units have Rome zones and it's so interesting that the light turns out to be the quantum of Light is also quantized Photon has a spin of one. That is, this is also Boson So the first classification is ready. we have sermions we have bosons we divided particles into two classes completely different properties but this it turned out to be little it turned out that the particles in addition to the fact that they have an angular moment They are still with each other interact one of the interactions We know well that they have electricity. there is electromagnetic interaction they have an electric charge sometimes particles with a positive charge negative charge with zero charge But it turned out that in addition to this particle still takes part of others interactions for example protons neutron is subject to nuclear forces which hold them and here is the second one ready for you classification some particles participate in strong nuclear forces other not those Particles that participate in strong interactions received The name of hadrons hadron is Greek the word hed ross means hard or heavy here are all the particles involved strong interactions are like this heavy particles there is another class of particles that is not participates in the interaction by their example is Electron these particles are enough light they got the name leptons from words leptus light So there are particles heavy A drones are light particles leptons it turns out that all particles which we deal with in nature can be divide into these two classes into drones or Ptons Besides this there are Particles which are related by interactions example is a Photon these particles belong to special class carrier class interactions These include Photon as I already said but later it was it was discovered that all the others interactions are also carried over particles appeared so-called intermediate vector base galleons Graviton and so on are new class particles are associated with the interaction thus with from the point of view of physical properties we are all particles are divided into three classes strong interacting with drones weakly interaction of epileptons and carriers interactions but the story is not over and here, as it turns out, hadrons are not truly elementary particles as it was subsequently discovered that they consist of smaller objects which came to be called fundamental particles as opposed to elementary ones particles of new terminology such particles of which all nuclei are composed particles were found that were named quarks thereby new fundamental particles or elementary particles if you like became the quarks from which everything is built hadrons and leptons which are still unknown such a structure does not exist in our country either in today's understanding is true elementary So we have some number of quarks Some amount leptons and also Here are the carrier particles interactions that I have already mentioned These particles are currently the most elementary indivisible fundamental particles we How to find out what they are made of elementary particle How to pour inside Elementary particles and understand if there something inside It is impossible to see this with a microscope So we need to do something somehow if you wanted to know how it works some other subject we would try break it Oddly enough, let's say watch we look at the watch and we can understand what's inside them If we break the watch gears will fly out from there looks like some wheels and we find out How a watch works How to be elementary particle it turned out that the quantum world is arranged differently It turned out that there were Elementary inside particles actually there is nothing maybe there is nothing at all we don't even understand yet if the structure elementary particle but still how to penetrate it which was found is the way to disperse this particle as much as possible to the very high energy and hit something target if we hit some target a remarkable transformation begins new particles are born and it's interesting that it is not that these New particles are inside those particles that we collide or inside the target No they are born from the energy of the collision here the wonderful Einstein works formula what is the rest energy of a particle equals MC squared, that is, mass multiplied by the square of the speed of light and if we dispersed some particle to very high energy and collided such particles then from collision energies can be generated new particles whose energy less than this genetically or mass which are less than so kinetic the energy to which we accelerated the particles here is a device that accelerates particles to very high energies is called particle accelerator and such accelerators began to appear very long ago in the simplest the accelerator is the electric field If you have electrical potential or the potential difference is electrical charged particles will move in this potential and accelerate in exactly the same way the magnetic field also acts, that is, in essence we use electromagnetic interaction electrical magnetic fields to accelerate particles Well, the simplest is something like this capacitor with potential difference and here it will slightly accelerate the particle but we would like to accelerate the particle not just speed it up a little bit to very high energies, these are cosmic rays such a natural accelerator cosmic rays are flying at us big member but in cosmic rays there are few particles It's quite difficult to study them, although at first the accelerator was the Universe but then decided that what are we going to expect from Universe Let's learn ourselves accelerate particles began to build speed up it is clear that if the acceleration is the length at which if a particle is accelerated, it is small, then it is not will have time to simply gain more energy the idea of the ring road was born in the center accelerator, that is, the particle will be move around the ring faster and faster and its electric or magnetic field they will constantly whip you like this the trainer whips the horses circus arena and the particle will accelerate stronger stronger such first accelerators were created in the middle of the last century They are called cyclotrons and strive was to receive maximum particle energy to accelerate when maximum speed The energy of the accelerator is measured in units which are called electron volts Electronic Volt is the energy that acquires an Electron if it passes potential difference of one volt Hence and the name of the electronic one is like this accelerators accelerated particles to millions of electrons the first accelerators were these units are usually referred to in abbreviated form as we you and here the particles accelerated to several memes these are millions of electrons Volts this is on actually quite large energies the speed of movement of particles it is already begins to approach the speed of light what's going on further on the way this particle can be used as a target just a piece of some metal or some gas or something else and particles hits this target the moment of impact a colossal kinetic energy is released energy of particles and from this energy new objects are born new objects are born particles were discovered in this way particles of which we didn't know that is to say, in fact, that it was just unclear and necessary to be born there it was to study the products of this very thing interactions The question is how to study them. How to see them. what was born on the accelerator it is desirable to somehow fix the particle there the particles are fixed or detected is usually called a detector At first, photographic films were detectors photo emulsions on which particles left a trace of some kind of gas chambers in which magnetic the field and particles left a trace like reverse trace of the plane in the sky but gradually modern times we we move on to computer registration detectors of what was happening there became very large but modern detector at the Large Hadron Collider is approximately like this four-story house And in this one the detector records all impulses particles angle at which it flies out charge particles there are special detectors which are recorded light particles leptons are particles are a special detector that records hadrons In short, it turned into a huge industry but the accelerators themselves were constantly increasing your energy in Russia or rather in the Soviet Union in at one time they were also built accelerators and the first cyclotrons appeared post-war years next is this accelerator science has been improving and the task was to increase everything increase the energy of particles Dubna near Moscow was built Synchrophasotron was the name of the accelerator which was built on a new principle so called autophasing That is, when magnetic field that whips particles to make it faster and faster moved automatically synchronized phase of motion and as a result of the particle accelerated to very high energies here The synchrophasotron which was built in in the late 50s in Dubna he accelerated particles up to an energy of 10 billion electrons naturally similar accelerators were in Europe in the United States and was some kind of competition to see who will have more energy next big machines were built in the Soviet Union accelerator in Serpukhov or Serpukhov accelerator for energy for energy already 70 billion electrons, that is, seven times more than in Dubna, but this record did not last long. A few years later it was built 400 billion electron accelerator Volt or 400k modern accelerators even more at the same time Accelerators are divided into two more classes: accelerators that accelerate electrons and accelerators that accelerate protons and other particles live very long time Therefore nothing happens to them, they can be accelerate moving along the ring of this huge accelerators and the rings keep growing and growing in size if Dubninsky accelerator has a radius of about 20 meters The Serpukhov accelerator is already in order there two hundred meters, let's say a ring accelerator in Geneva which is now there in which was first built electron accelerator and then protons The accelerator ring is size 27 kilometers in circumference, that is approximately like the Moscow metro's Circle Line the accelerator becomes completely gigantic structures But why is it necessary Why build such a big accelerator? such huge sizes are needed The thing is that trying to achieve more and more we need more energy all the time and the greater the magnetic field that will be wrap the particles in a ring otherwise they they will just fly away The smaller the radius acceleration The stronger they need to be wrapping means more is needed magnetic field creating strong magnetic fields this complex Technical task Therefore, if we build an accelerator a larger radius can be used smaller magnetic fields from here the size of the accelerator but that's not the only thing another reason The second reason is that that moving in orbit around the ring accelerator electrically charged particles electrons and protons emit light this light is called synchrotron radiation so here's what The stronger the Electron wraps itself the more it emits light and loses it energy at some point energy loss will be comparable comparable to that the energy that we pump in to accelerate the particle therefore exists natural limit Greatness of radio with accelerator we reduce these losses by we can accelerate the particle to the Big Ones energies So accelerating particles to the Big energy We strive to increase the radius accelerators so that losses are minimal and therefore the accelerator is very large and such accelerators accelerate particles which then strike in the target it is called an accelerator with a stationary target But soon it was It is understood that a large amount of energy the accelerator is simply spent on the fact that particles hit the target trying move the target from its place And in fact energy goes into the movement of target molecules that is, in the warmth a very large amount is lost energy that could go to the formation of new particles an idea was born colliders collider is when there is no stationary target when we accelerate two beams of particles they collide with each other with a friend Means from the English word kalight collision and such modern accelerators of this type mainly colliders For example, the large hadron collider in Geneva which is now works on which there have already been openings that we are expecting new discoveries this is the collider there two proton beams collide, that is accelerates in one direction around the ring protons and in the other direction and then they collide at the points of intersection of these rings and this is the collider problem colliders of course consists in the fact that these two beams which are very narrow are not must pass each other They must collide that is to say it should be very tight focusing of these beams is also a big technical problem that to fortunately I found my solution and now the colliders have started working in Geneva that very ring where the big one was built Hadron Collider where they collide protons before this in the same ring electron positrons collided was Electron Positron Collighter then there is a modern accelerator, it is a collide but there is another class of acceleration that's true called linear accelerator linear There is no particle ring in the accelerator at first accelerated in ring accelerators Then it goes straight to the road like this such a high-speed track and they are already flying towards each other if at the expense of special technology to provide very large acceleration gradient then despite that they pass this section speed only once but these particles manage to gain colossal energy and collide with each other in this case there is no energy loss because no particle rotations are made they just rush towards each other so called linear colliders already exist But now there are large international linear project the collider is 50 km long, this is the length is determined by what you want to get very high energy And the longer the length the more energy here is a project like this There is no international collider It is possible that in a few years its construction will begin in Japan each accelerator has its own of course advantages and disadvantages but Home the task he solves is to disperse particles to the maximum possible records that have been achieved now acceleration is 200 billion electrons volt for electrons and positrons in big large ring collider so called power transmission line Electron positron collider in Geneva set a record for huge colliders is the large hadron a collider in which protons are accelerated up to an energy of 7 trillion electrons This is currently the greatest achievable Energy and It allows give birth to particles with large masses that still exist were inaccessible to research and first an example was the birth of Hex boson at the Large Hadron Collider the present moment of physics hopes that this will not end and they will wait new particles and drones are strongly interacting particles once upon a time there were few Drones Proton Neutron and the bimeson proposed by Yukova but then there were a lot and it became necessary some classification and the first classification It's pretty obvious it is connected with angular momentum it turned out that All drones either have whole angular moment proper angular moments or spin as it is commonly called or semi whole and drones are half whole angular moment is called baryons and hadrons in general, angular momentum is called misons here we have the world of baryons and Mizon Proton Neutron are baryons pemizon is meson it turned out that there are a lot of them and they are needed it was necessary to understand how it all works and why are there many of them and how will they arrange and when there were about a hundred of them, it was clear that This classification was not just supposed to be place them in the classroom but also explain their properties and it turned out that there is very interesting mathematical schemes in which particles fit in This is somewhat unexpected and This is called group theory mathematics the concept of a group in mathematics in general Of course this needs to be explained somehow but it is intuitively clear that if there is some transformations that we can do for example turn around on one leg around yourself This is it the transformation we made is clear what if you roll over once or turn around a second time it's all the same that turn twice like this transformations and is called the transformation of the group is a bit like that I explain the primitive on the group model this is a transformation that can be done one and the other are equivalent to the third there is an inverse transformation, that is turn around on your foot in the opposite direction or single transformations, that is don't turn around at all and all that forms what mathematics is called groups group all classified their a finite number of them have certain dimensions certain properties here It turned out that A drones can do everything classify mathematical by group theory there are special groups of matrices The matrix is a table, let's imagine it Tables Two by two elements 4 2 columns and two rows of the table, this one Matrix and it turns out that there is such a thing matrix transformation group and here hadron particles get into something like this the elements of these matrices are here such tables and particles fall into the elements of these there are matrices tables there Two by two there are three by three there are four by four if you guess the group correctly then we can say how many elements tables means particles should sit in in these elements if some particle is missing And there are tables, you need to try to find them a new particle that is exactly will fill this matrix Here is approximately this is the path these tables or these took matrices are associated with a group that bears the name special unitary non modular group with three elements su3 it turned out like this that all particles can be arranged tables in accordance with this group these tables form eights nines tens and all the particles sit in these elements and it turned out that all hadrons you can plant them in such a successful way these matrix elements were thus New hadrons predicted To fill there are gaps in these tables and it would seem that we finally understood how it works this world of baryons of their drilled zones their tables were hit bison leptons were included in other tables and everything seemed to fall into place but then suddenly some started to appear Particles that are not in these tables got there and it turned out that it seemed like probably the table is not complete but on the other hand sides seem to be if there are tables behind there should be some kind of maybe behind this too there should be a clearer understanding if particles about a hundred then naturally arises the same question as arose in the atomic physics if there are about a hundred atoms chemical elements maybe they are from something simpler consists of them just how to deal with these from a cube elements Well, like atomic nuclei, there are about them hundreds of them are built from Proton neutrons are just needed a certain number of protons and collect neutrons there and you get it atomic nucleus same thing with drones it turned out it turned out that these are these tables these are the symmetries as they are accepted they are called related to what is smaller objects from which it is possible build android first these objects were perceived solely as math toy because the mathematical group was formed and here is a mathematical toy two the person was actually offered these objects are one of them prednazol suggested calling them aces but He probably loved card games and that's why the terminology is so card-like It is interesting that when he wrote the scientific work and proposed a classification of all hadrons with the help of these aces and They refused to publish in the magazine, they said that card terminology is not suitable and another one suggested calling them quarks quark is such a strange word comes from a novel by James Joyce pominkinu and there is such a poem there where it says three quarks for mister mark This is a strange word quark was taken by Muram Hermann Nobel the laureate who was involved in this classification and another physicist who suggested suggested calling them aces Georges Wyke This is his terminology the terminology took root and here it is It turned out that all these are classifications of everything hadrons can be understood if we assume that they consist of smaller particles called quarks and at that moment there were three quarks, it turned out that all baryons, that is, particles from the back, all drones with a spin half whole are built from three quarks and all zones, that is particles from the back the whole is built from two parks turned out to be Everything is very simple There are three types of quarks and they are what everything is made of world all strongly interacting particles some of three quarks, others of two quarks this is the quark scheme at once explained the structure of these matrices in which hadrons were put in and it turned out what are strong interacting particles They are not really elementary Elementary they are all made up of quarks spun around quarks soon quarks were recognized as real particles not just a mathematical scheme The thing is that in experiments in Russia on accelerators hadrons very similar to the experiment and Rutherford when he bombarded the foil and discovered the atomic nucleus like this In experiments in Russia it was discovered that indeed, inside the baryons there is something like there would be three grains, three quarks, and inside bison eat like two grains quark what is quarks it really such Particles that are inside but the amazing properties of these particles they never fly out This property is not yet fully understood but it is established quite accurately that it turns out that these particles are always as if are trapped inside hadrons then yes, we know that there are three of them inside they never fly out of the baryon they are connected to each other by very large forces and when they try these masonry will fly apart in different directions then the forces are like springs, they are pulled tight and do not let them in And if this spring breaks then at the end a new quark is formed and new drones are formed in this way from one drone during interaction many hadrons are produced, they all consist of from the quarks of the world of Drones was understood thanks to the quark models that have received great development and confirmation has been around for a long time now three types of quarks they were called up Lower and strange these three quarks existed until new ones were found Particles that didn't fit into the pattern those matrices and it turned out that for them explanations A fourth quark was needed and further This story continued Well I I don't want to talk about it anymore now quarks about quarks but the structure of hadrons it began to emerge quite clearly that if they consist of quarks then it is necessary just go through all the possible ones combinations these are all possible combinations must exist but interesting thing that indeed all hadrons consist either two or three quarks the question arises: why not from four? or Why not five of these hadrons were also subsequently discovered. Although they not as reliably open as usual nuclear they are called exotic hadrons this is what it is now current topic exotic hadrons are built from four five or maybe six quarks what what happens to drones when they collide On the accelerators here we are we say Large Hadron Collider there hadrons collide in this case we we say Proton collision Proton is the simplest hadron is a baryon it consists of three quarks what happens when two drones collide in boosters It would seem that they should. As if flatten out the quarks should come out but this does not happen due to amazing property of quarks due to those interactions that connect quarks with each other it turns out that when the collision of two hadrons is born new hadrons these New hadrons fly out from at high speeds in the form of such jets From a large number of hadrons in one a huge number of particles are born in the event if the energy of the original protons is high then more and more heavy ones are being born hadrons it turned out that some particles they are very heavy they have mass approximately the mass of the average atom But all these hadrons turn out to be short-lived and since they are they usually get heavy very quickly decay decay time very strongly varies from 10 - 6 seconds to 10 minus 17 18 seconds Particles that live so long are usually called resonances for short cannot be seen as normal particles they are so fast they fall apart they are simply observed in processes in research in the form of some peaks their distribution by energy Like this resonances of huge were discovered very many but they all fell under that the classification that I said all of them fall under this scheme and they all consist from quarks and knowing the quark structure we can talk about the properties of these particles naturally the question arises: They are not there is nothing new there are some new hadrons that we know nothing about here As the energy increases as as the masses increased, new ones were born particles It seemed to me that some of them they disintegrate so quickly that they simply don't manages to exist in the form of related states of quarks, generally speaking, if we say that particles consist of let's say something and the drone consists of quarks This means that these quarks are bound. between themselves Usually they talk about connected states so these are connected states may simply not form if they don't have enough energy and that's it some drones actually practically does not exist because the condition is not related to this in the sense that it is possible that we have already achieved on accelerators of some limit further which heavy particles will not be will be formed because they will be disintegrate faster than it forms related states such examples We have already exist but the properties of hadrons as particles which interacts strongly they Hadrons are fairly well understood electric charge therefore in addition strong interactions they accept participation in electromagnetic interactions and also disintegrate and the decay is carried out by weak interactions when as a rule a neutrino is emitted. That is, a hadron is Particles that take part In almost all known to us interactions they participate in strong interactions in both electromagnetic and weak Well and also gravitational which really very weak [music] the mysterious word quark sounds unclear And this is what attracts us the word actually appeared in the novel James Joyce was even there at the Fox a poem that was called three quark for mr mark What did these quarks mean? it's not clear from the word "liked" and when sixties scientists were engaged in constructing a theory elementary particles under elementary At that time, particles were understood mainly what we now call a baryon or misons typical representatives are Proton or netron which forms the atomic nucleus so that's when we were working on building the theory these particles And at that time it was very many of these quarks came to they began to use them in the yard whole Use came up with this scheme American physicist Murray Gelman he the winner of the Norilsk Prize is very a famous person and was the second one the man's name was Zweik he used another word for aces, he called them aces apparently the quark took root and turned out to be more with a beautiful word nature as it seems to us now that we for now we understand that it is built according to the Russian Matryoshka principle that is, there are several layers of us we open a new layer each time and there something new appears there is an atom in it there is no atomic nucleus the nucleus consists of protons and neutrons were once thought to be these protons and neutrons are Elementary particles Then it turned out that there were such particles much more first in Space rays then became accelerators discover more and more new particles of them several dozen were formed and there was a desire to somehow classify create something like the periodic table that were what rows of columns are all these particles were doing their own stave in this table and it turns out that this can be achieved create something like a table Mendeleev if we assume that everything particles consist of certain components that is, Matryoshka goes further into the depths what protons neutrons camisons Rome zones and so on and so forth those Particles which we discovered that they consist of even smaller components that they suggested calling it a quark it turned out at that time that in order to to make up all the particles is enough three of these bricks These bricks were given three names top bottom and strange here is the mind d and s English words Up Down and Strange Well, how are particles built from these? the most quarks but very simple Well for example Proton we take two uquarks 1D quark uud is proton Neutron take udd this is Neutron possible take trium you can take 3D you can take UDS is possible In general, everything is listed possible combinations and it turned out that all known particles can be constructed from these three That is all that we knew before it is still possible to build from these three combinations, that is, just like that, from three components could be built the whole world of elementary particles it was great but it wasn't just like that this is how the game is in the cube behind these cubes there was some kind of mathematical construction This Theory is called in a difficult to explain way groups Well, let's put it this way this theory said that everything the particles should form well like this families these families could consist from three particles from eight particles from 10 particles and it turned out that everything Elementary particles which are also time they were open very well they fit into these very same simistas and thus we even got some unoccupied places in families and then they it was as if this path was open particle construction it was named in the eightfold path is connected just group theory I probably won't explain Well, everything was so wonderful and good until then 74 in my year there was no open any a new particle that is not in this scheme was fitting in Well, at first there was a lot of incomprehensible noise. then it turned out that in order for her I had to come up with another one to explain particle another quark 4 and it turned out four quarks, that is, this one wonderful poem three quarks Mr. Mark Well, I had to a little bit I had to leave him to give birth to the fourth Quartz moreover it turned out that when Physicists tried to build a theory that describes not just the presence of particles describe their properties, their interactions and mutual transformations of three quarks turned out to be a bad combination It turned out that, for example, some decays particles that for some reason do not exist in nature what happens in this theory is the opposite should happen were good to happen And when it all analyzed and realized that if only 4 there were quarks at all if there were an even number there were quarks then everything would be just like that It is precisely these decays that would be needed are forbidden and all nature would fit in that's why the fourth quarks said earlier but it was opened in 1974 the particle of quarks became 4 and all were happy and everything worked well but after The Fifth Quarter was opened for a while by the way, they discovered the fifth particle 4 The quark was named the Charmed Quark or in English This Enchanted Quark has reborn a whole physics charm or enchanted and then they discovered the fifth quark which got the name backwork or in English the word Bottom or from the English word Beauty, that is lovely or beautiful and appeared lovely physics the quarter became five and again there was that the biggest problem is with their transitions alone particles are different and it is clear that the road was already everyone started talking about the beaten track there must be a sixth one, they started looking for a sixth one and at the end of the last century it was found the sixth quark it was called T or top or Coward and Here is a system of six quarks Now we say that there are 6 of them But when i became 6 it became possible already think not just about the fact that all particles they are being built from, one could already think about own classification of the quarks themselves there are six of them and it turned out to be very It is a curious property that these quarks are grouped in pairs the first pair is y and d quarks, these are the ones from the very beginning there was a second pair - this is S and C quark or CS is more correct to say and third pair This is top and bot and these pairs quarks turned out to have absolutely each pair has identical properties The only thing that distinguishes them is that each the next pair is heavier than the previous one A otherwise they are absolutely identical and then the idea was born that in fact we we are dealing with well, as if what we received the name of the generation may not be the most a lucky word sometimes in English uses the word Family, that is, family there are three families or three generations here the first quarks are the first generation second pair second generation third pair third generation and they are absolutely identical only one generation older another in the language it's harder to start in this case, here it is three generations the question arises why it is actually necessary three generations What the world consists of which we see with you, it consists of there are no more protons and neutrons but also Electron but about Electron I'm still I'm not talking about quarks, but there is a Proton and Neutron why did you need two more quarts? then two more quarts This riddle the whole visible world remains, that's what we are we see each other what we are sitting on where we are we walk the air we breathe everything that we observe stars around us that want consists of two quarks More precisely speaking consists of protons and neutrons which are made of two quarks It's very interesting how these quarks are properties Well, let's say a proton has electric charge in units of electron this charge is plus one Neutron has no charge primer if they form protons and neutrons must have an electric charge so that the total charge is the desired amount because the Proton consists of three quarks it is quite natural to assume that electric charging cooking multiple 1/3 This is how we choose an electric charge the charge of a quark is two-thirds of the D of a quark minus 1/3 means Proton how it turns out uud two thirds plus two thirds minus 1/3 it turns out plus 1 And how is Neutron made udd 2 3 minus 1/3 Minus 1 is 0 all baryons are strongly interacting particles having half an integer spin 1/2 3/2 and so on, these are all the baryons consist of three quarks each quark has a spin of 1/2 of the three these same halves are collected half-integer spin of the baryon and, accordingly, We always build combinations of three quarks And here are the so-called nizons have spin 0 so they are built from two quarks, say with spin or plus half or minus half Here for example the famous pemizon pi meson is carrier of nuclear forces it has a dorsal and its charge is either plus one either minus one or 0 it consists of two quarks how to do it for example take or antid I forgot to say Probably that all particles have antiparticles as well quarks are antiparticles antiparticles have opposite electrical charge, if we take, say, quarks antidequak charge 2/3 at declark minus 1/3 accordingly plus at the bottom So everything else is like this in the form of quarks with fractional charges all observed Elementary are constructed particles leptons light weakly interacting particles one of the leptons We know well this is the electron particle that was was one of the first to open over 100 years ago back The electron is the very particle that leaks in the wires when there is one electric current turned out to be Electrons are not the only particles in of this family of liptons soon after the electron was discovered another particle which was named mion she turned out to be almost a complete copy the electron is only 200 times heavier in general The electron is the lightest charged lepton if its mass measure in units that are accepted in particle physics And this is energy units it follows from Einstein's formulas what is rest energy equals mass times square the speed of light, so the mass is usually measures in energy units mass an electron is equal to half a million electrons beon is 200 times heavier the next particle that was discovered from the family of leptons This is a taulipton she even more difficult I must say that all these three charged particles are they are almost exact copies of each other absolutely identical properties electric charges And in general they conduct themselves are identical and differ only in mass But it turned out that these three particles are not exhaust the entire family of liptons in decay time together with electrons another elusive particle is born At first it was unclear where it went missing energy and then pauli suggested that she be carried away neutrally a light particle which the farm offered call it by the word neutrino, that is a small neutron, so physics entered nitrine inside on very small mass and there is no electric charge it does not takes part in strong it is very difficult for her to interact discover nevertheless she is born weak interactions so together with electron is born from electron neutrino and what is born with the mion too a neutrino is born and at first they thought that these two particles are just the same but then it turned out that no, they are different from each other and then decided that each Lipton most likely enters with his partner Electron with electron neutrino mion with mion nitrine and Tau he became us netrine by the way, there was a town nitrine opened in 2000 This is the last particle from the standard model that we we know which was opened in the past century so here we have 6 leptons three charged and three neutral all these electrons satisfy one and the same equation is usually called Dirac equation and satisfies particles with spin 1/2 quarks as particles with spinal 1/2 also satisfies dero equation but with nitrine the story is more complicated. The thing is that nitrine has no electrical charge And if the particles have no electric charge then she could satisfy another one too equation such an equation exists it is called the Mairan equation in Honor of the Italian Physicist and Tore marjoram so this is the level it satisfies nitrine Gerakovsky or Mayranovsky or in other words is mine nitrine de Rakovskoy particle or Majorana particle What is the difference? The difference is that if the particle is Majorana then it is its own antiparticle it means that there are two such particles Having met in the Universe they can Mutually annihilate If it is Iraqi particle is a process impossible to understand how it really is what equation is nitrine arranged on satisfies need to conduct an experiment and check if this is happening mutual annihilation of two neutrinos such An experiment is currently being conducted called this is netrin-free double beta decay and so far the result such that we cannot answer the question is neutrino-Dirac or Majorana perhaps in the future we will find the answer to this riddle what are remarkable neutrinos besides this The thing is that all quarks are leptons and other particles during interaction they pass quarks of the same to each other varieties are transformed into quarks of another variety leptons of the same type also transfer We observe these processes of a different sort but with her three on a special article The thing is that such a transition of particles of one varieties in another usually occurs on distances that are completely impossible experimentally notice But if the particle is very light and not trines presumably very light then these distances become noticeable and already reach macroscopic proportions meters or even kilometers and here it turns out that what usually happens is is called an oscillation phenomenon when nitrine is distributed in the environment and at first we observe one variety not trine at some distance for example from the reactor if not three is born in the reactor after some time distance from the reactor We see that the number of varieties of this netren It happens But then another neutrino appears sorts this law is described by sine sine functions that is what happens oscillation of one type of netrin and another this effect is called effect neutrino oscillations I already said that with other particles we don't see this because of the distance which are where the oscillations occur is completely microscopic They are inversely proportional to the mass A in this case the mass is very small therefore the distance is big so these are not 13 Were experimentally discovered It must be said that the transition of particles of one varieties in another is impossible if particles without mass it happens only then when particles have mass Therefore netrin oscillations are clear to us indicate that nitrine is massive particles Although the mass of this extremely small I wonder what we still have we still don't know what this mass is because untrained oscillation confirms itself the fact that this mass exists allows measure only the difference in oil between various nitrines but does not allow measure the absolute scale of mass therefore What is the mass of a non-twin? This is also still the case. remains a mystery We hope that other experiments which are already sensitive to the mass itself will allow us to answer this question experiments with neutrino searches are always it is very difficult to explain this because neutral particle practically does not interact with the environment those nitrines that fly from the sun permeate the earth and we are completely unaware of this we don't feel it because there is interaction very weak We are practically transparent to neutrino is therefore very difficult register the interaction of this particles to do this detectors must have a huge volume to increase the likelihood interaction of nitrine with any a particle of this huge volume for underground ones are specially created for this laboratories underground because you need to try shield the experiment from space background from those particles that fly to to us from space, that is, cleaner than the laboratory the more likely it is that we will be able to register the items of interest to us events And here are such underground Large installations are being created in laboratories in which they are trying to register signals from nitrine here is an example bring the so-called laboratory super kamikanta which is located in a salt mine near Japan kamioka villages are a barrel the size of 40 meters high and 15 meters in diameter filled with the purest water and all the walls it is occupied by photo multipliers any signal that happens there this colossal volume will then be transmitted via photo multipliers detecting something like this the size of the installation is made underground which are capable of editing not three what did you manage to detect? It turned out to be very interesting before only the signal from nitrine is detected coming to us from the sun for a long time there was a mystery that according to the models of the sun a certain amount of stuff should fly to us the number of electron neutrinos to us arrives and much less thought that there must be something wrong with ours understanding and then the riddle was solved It turned out that the phenomenon of neutrinos oscillations explain everything part of nitrine which fly to us from the sun electronic neutrinos turn into meme days trines therefore the number of electronic Dmitry on It turns out less Like this and like this phenomenon of oscillation phenomenon of solar neutrinos have been explained but there are others neutrinos are showcases that fly in to us from cosmic rays as a rule it is million and these mine nitrites also turned out to be not as much as necessary And again the phenomenon oscillations made it possible to explain why the amount of nitrines is not met our initial expectations There are several at the moment There are so-called sources of neutrinos solar neutrinos are cosmic neutrinos are nitrines from nuclear reactors but nevertheless all this neutrinos of three types are electron neutrino mionic wind taonic neutrino But it turned out that all of them associate, that is, get confused with each other friend and generally speaking it is necessary somehow it turned out that it was possible to unravel all this all these confusions are described a certain number of angles three angles well, like the usual turning angles these three angles are now experimental measured and it turned out that everything experiments on both solar and atmospheric reactor neutrinos are good are described by a standard model with a certain the rotation matrix is the Matrix by the way called the Pantecorovo Matrix maki nakagawa sokata there is one here Italian physicist who worked in In the Soviet Union Bruno the Pantheon-cow and three There are Japanese ones in the Park sector too This is the Matrix, it is usually called matrix cabiba cabaya shimaskal also one Italian physicist and your Japanese analogy between quark and lepton sector has manifested itself and there is mixing flavors as is customary speak in clark sector exactly the same mixing of aromas in in the electronic sector these two matrices mixing explains all the transitions of quarks and leptons of the same type into quarks or lepton of a different kind Well and in particular explain all phenomena neutrino-hasculations now all these angles well measured, everything matches expectations and there is still one small one left the riddle is the phase that is in this matrix Well if anyone knows what it is complex number then complex number there are modules phase so here is the phase that there are still some things in this matrix that are not yet very well known Although also experimental measurable quantity of themes the very picture that emerges looks like so we have three generations quarks and three generations of leptons first generation is the upper and lower quarks electrons electron neutrino second generation Charmed quark strange quark neonion nitrines and the third generation up quark down quark and that's it taonic this is three generations it turns out such a complete analogy between leptons and quarks I just wonder why these three are needed generations are a mystery that still remains to be answered But here are three generations quarks electrons are the basis of the modern model of elementary particles I must say that nitrine which present in the lepton sector plays a very important role in cosmology is the matter of that nitrines are stable particles and as stable particles but it just doesn't exist into which there is no lighter particle to decay She has existed since she was born in early universe and properties of the early The universe and the general properties of the modern The universe depends very much on that How many types of nitrine are there in this universe? there is a distribution so here it is heavy elements in the universe microwave fund of the universe and many other facts indicate that the number of neutrinos is most likely equal to 3 This means that the number of generations is equal 3 If we talk about quartlipton symmetry and talking about generations is not really true there's still some snack left It's possible that In addition to the three generations, there are still trines that do not participate in any what interactions are not in electromagnetic neither in strong nor weak such nitrites are called sterile Experimental window for sterile neutrinos still exist perhaps the nearest experiments remain will allow to answer the question is there sterile neutrinos or not sterile neutrino If not then quark electron the analogy will be complete if there is one so it turns out that neutrinos are giving us something after all new riddles symmetry It turned out that this is the most important concept in physics elementary particles from the point of view Mathematicians are essentially physicists elementary particles are theories of symmetry on the other hand, a common concept symmetry should be very good for everyone I know, symmetry is some kind of thing the similarity or unchangeability of something when transformations Well, for example the human body here we are looking at it is symmetrical in relation to a person reflection relative to the axis passing through center of the body left side of the body and right body part is the same Here are the symmetries the simplest symmetry of reflections but we we know that the heart on the left means symmetry incomplete So it is only visible but however if you don't talk about human entrails then this is an example symmetry another example from everyday life Another everyday example is a snowflake snowflakes are very beautiful they are there hexagonal or octagonal there are no such things But nevertheless they always have some kind of beauty symmetry What does symmetry mean what if rotate the snowflake, nothing will change but you just need to rotate it and arbitrary and accordingly on such angle so that the snowflake coincides with itself So there is, as they say, a group snowflake invariances these are the groups Well, there are realities, physics is everywhere. so if we formulate the concept strictly symmetry is the immutability of something for specific transformations Here's about the human body we are talking about reflection about the axis for a snowflake we are talking about revolving around Russia It turns out that all transformations can be classify it is called theories groups and different groups play very particle physics plays an important role in this the transformation can be as continuous when the parameter is simple arbitrary number and can be like this interdiscrete when we say we turn only at a specific angle we don't just rotate, but we turn on angle let's say pi in half or 15 This is a discrete transform the reflection of the human body is also discrete transformation because we just change left to right when we look in the mirror and we see there the display is also a transformation Reflection say you know that if you look in mirror then the left hand becomes the right and right left so if there is sameness then the mirror world coincides with our world If our hands are somehow different, then we don't have worlds that don't match, for example the heart is already the man's heart in the mirror with another sides So we don't have a full symmetry mirror world all this manifests itself physically If we talk about discrete transformations that are the most popular transformation is reflection spaces that is changes directions in space here are the theories that describe physics elementary particles they are usually invariant, that is, unchanging relative mapping of space there is a time display, that's different transformation we know that in everyday life you can't turn back time in life time flows only in one direction A here is particle physics can particle physics as a rule it is formulated So that time can be converted another transformation change of sign of electric charge so we'll just go ahead and replace the signs electric charges and all particles electronic will have a positive Proton charge negative charge and so on further the question is will the world change whether or not there are some elements from the world some will not change some will change This too symmetry it is not exact there is a continuous symmetry Well, let's say It is known from quantum mechanics that there is a so-called wave the function is a complex number for him there are phase modules It turns out that the phase can be continuous change And at the same time the observed value will not change. So there is symmetry with respect to dimension phases phases can be changed continuously this continuous symmetry or phase symmetry turns out that with every the laws are related by symmetry save something must be saved if there is symmetry Well here is the phase symmetry leads to conservation electric charge here it would seem abstract transformation she explains Why is electric charge conserved? there are other examples it turns out that if you find symmetry then you can find the properties of the theory or vice versa we need to formulate the theory so that it had a certain symmetry then those principles will be observed which we put into it principles that underlie special theory of relativity associated with immutability physical phenomena when the system changes countdown so we have to include it in the theory symmetry with respect to changes in the system This is commonly called the Lorentz UFO reality That is, this is the symmetry that changes the frame of reference or changes coordinates in space It turns out that the construction of any particle physics should have a lot of all sorts of symmetries are very limits the construction of the theory at the same time time tells us what is right build a theory when did particle physics become develop was discovered There is there are many other symmetries that we haven't seen before It is known Here are some interesting ones, for example properties of quarks it turned out that the quarks that form hadrons are fermions and thus cannot be in at the same time ground state with the same energy Because when you rearrange them the sign of the wave function will change if they are absolutely identical then it is lunar the function will be equal to zero None there will be no hadron This problem was solved by introducing color like this called quark in color it is conditional concept you could take any word and postulated relative symmetry that you can change the color continuously in any way it is symmetry finds mathematical embodiment in the form of so called special unitary group strive for colors and therefore the theory of quarks is constructed so that it is invariant regarding this very group it turned out that the presence of symmetry is not only leads to conservation of charge But in in this case with quarks conservation color charge but also tells about what interactions between these particles here modern theory of elementary particles This is essentially a theory of symmetry often very saying that standard The model is based on three groups Symmetries all these groups are very similar on top of each other this is a special unitary groups are group su3 su2 and o1 this is how they are designated in mathematics here is every theory it should to satisfy accordingly certain symmetry If we talk about modern theory of elementary particles then in addition to these three symmetry groups which I named There are also discrete symmetries which are also mentioned this reflection of time reflection space of particle replacement antiparticle And there is also relative change of reference system here is the modern theory of elementary particles it has all these 7 And how I already said that the presence of symmetry is not just determines what particles are there but it also defines how they are among themselves interact It turns out that from the presence of phase symmetry which I spoke ensures preservation electric charge so here At the same time, this symmetry leads to the emergence of a photon or ordinary Light which is a carrier electromagnetic interactions And here let's say the presence of color symmetry of quarks leads to the fact that there is special particles that are carriers of strong interactions quarks these particles were named galleons from the word glitch glue that is, symmetry essentially determines the whole particle physics sometimes even so they say that it doesn't matter how you are formulate formulate a theory the main thing is what kind of symmetry is this theory has symmetries may not be exact this is very interesting situation when symmetries it's a little bit broken here again complete analogy with the human body It seems like there is left-right symmetry but one eye might be a little squinted or one ear may be slightly different other and left right symmetrically It's a little bit broken. Here's the physics. elementary particles exist the same situation some symmetries are violated As an example, let's say symmetry relatively reflection of space and time is not violated at all electromagnets interactions and is not violated at all strong interactions But weak ones interactions break this symmetry usually spatial symmetry call the letters p but symmetry with respect to reflection time of the letter t asymmetry relative the replacement of a particle with an antiparticle is called letters C and there is even one like this the theorem it is called cpt theorem about that that the theory of elementary particles should be an option regarding cpt transformations It turned out that it turned out that they were strong electromagnetic interactions but real relative to all these transformations separately but here weak interactions No at first there was It is understood that parity is a reflection spatial symmetry not it is saved then it was discovered that charge symmetry is not conserved and the concept of combined was introduced symmetries when we replace space reflection of space and replace particle to antiparticle in fairy mana the lectures even have a wonderful phrase that positron is the antiparticle to the electron An electron that moves backwards time this is indeed so but in the future it was discovered that this is also a symmetry this very interesting phenomenon is violated particle physics what weak interactions are disrupted and this is it combined symmetry and only combination of all three symmetries of the CPU and t is not violated another example of broken asymmetry is this the fact that any asymmetry always leads to the fact that the particles must have zero mass those particles that are responsible for interaction Photon has zero mass symmetry is not broken Glen has zero the mass of symmetry is not broken But the weak interactions of particles carrying these their interaction is called intermediate vector bosons They have neither zero mass This means that symmetry must be violated This is a completely separate interesting topic. about how it violates the symmetries of physics particles as the symmetry of the weak is broken interactions This is usually called spontaneous symmetry breaking that is, symmetries can be broken there may be some inaccuracy however even if the symmetry is broken still, part of it remains and determines in fact, the configuration of the entire theory I wonder what to answer to the question what symmetry is sometimes more complex than find some particle because this symmetry does not always come easy it is not without reason that the success of hadron physics can be seen and the classification of Drones was related to that that symmetry was found and then called so3 symmetry which allowed classify all particles modern development of particle physics too is associated with new symmetries on one sides are the asymmetry between quarks and leptons which are also possible is expressed as a mathematical formula which has not yet been found, but on the other hand sides the emergence of completely new ideas symmetries for example symmetries between particles of integer and half-integer spin are called boson particles and fermions here symmetry between the base farmers is such symmetry was named supersymmetries if the theory has supersymmetry then this means that each flowerpot in theory has its own partner fermion That's about the same as The electron has nitrine A as its partner here it is connected with the group so2 A here the Electron must have its own partner some scalar particle such particles do not yet exist in nature discovered so is it symmetry of the correct symmetry of nature or not it is unknown However it is is now the subject of the most intense searching is in some sense a task number one modern collider Since school physics we have been faced with the concept of power there are different forces, there is the force of attraction there is friction force there is rolling force there is elastic force There are many different forces us to what not all of these forces are fundamental often very strong are a secondary phenomenon Well, here it is the friction mercilo is secondary this phenomenon is actually interaction of molecules and even the interaction of molecules can be secondary For example, molecular Physicists have van der waltz forces these forces are a secondary consequence electromagnetic interactions I want to get to the bottom of it fundamental force what is it fundamental forces in nature which defines everything without which all these secondary forces are built Well, here are electromagnetic forces or electrical forces are such fundamental interactions as we we understand Now we will say Coulomb's law This is known from school physics fundamental law but it is generalization it follows from the equations Max Maxwell's equations generally describe everything electric magnetic forces in nature therefore electromagnetic interaction are fundamental forces of nature another example of fundamental forces nature is gravity again, the law is known from school Newton's universal gravitation which now I have already received a generalization in Einstein's equations we now have Einstein's theory of gravity gravity forces are also fundamental interaction in nature and once it seemed that only these two fundamental forces exist but later we realized that no, it's not so in particular the atomic nucleus when it were when it was opened and arose the problem is to understand why the particles are retained within the core and do not the concept of nuclear was introduced forces these nuclear forces were measured understood described but later it turned out that they too it is not fundamental that nuclear forces in in some ways resemble the Van der forces waltz truth fundamental forces providing strong interaction are the forces between quarks quarks interact with each other and how secondary effect of each other protons and neutrons interact in core fundamental interaction is the interaction of quarks with by means of the exchange of so-called gliones So this is the third fundamental force in nature Well, here the story is not it ends up that the decays particles and particles disintegrate all heavy the particles break down into lighter ones like this here is the decay of elementary particles are described by a new interaction which was named weak interactions are weak because forces this interaction is noticeably weaker than electromagnetic strong But it turned out that the theory of the weak interactions which initially existed and described very well All decays worked poorly when increased energy and it was replaced with a new one the theory of weak interaction which turned out to be completely universal and built on the same principle which all the others are built there are interactions in the modern world four fundamental interactions damn it I'll also say this like these four fundamental interactions electromagnetic strong weak and gravitational is built on one in principle consists of this the forces between particles arise due to exchange with some intermediary carrier of interaction electromagnetic interaction is built based on the exchange of a quantum of light or quanta of electromagnetic waves are Photon Photon is a massless particle charged particles are exchanged and due to this exchange arise interaction between force particles between particles Coulomb's law is also like that is described another strong interaction there too there is a mediator there is also a particle which exchange quarks these particles They are called glions, there are 8 of them, that's also massless particles third particle third interaction is weak interaction And here too the mediators are the Particles which are called intermediate vector bosons these there are three of them but they are massive there are they quite heavy of this mass the gravity of these particles and explains why weak interaction is so weak the fourth interaction of this gravitational and it is carried out by exchanging a quantum of gravitational the fields are called Graviton it is worth saying this Graviton is still experimental if quantum gravity had not been discovered we we don't fully feel it yet and we don't fully understand it describe So all interactions are the act of exchanging some particles here we return to the concept symmetries any such interaction related to symmetry symmetry says about how many such particles are there and what is in their mass if symmetry exact mass photon has zero mass 0 carbon has mass 0 if symmetry is broken the mass is not zero in intermediate vector bosons bosons mass is not zero there is symmetry broken gravitational symmetry is not broken graviton also has mass 0, so there are four fundamental interactions they actually explain everything we see all other forces are just that a secondary effect of these interactions but In 2012 a new one was discovered a particle that became very famous this is the so-called hex bason Hicks's bason is also carrier of interactions between quarks and between leptons therefore Now is probably the right time to talk about it that the Fifth Force appeared as the carrier of which is Hicks bazon Here, too, the symmetry is broken Hicks Boson is massive particle thereby number of fundamental interactions particle physics usually uses the word not force but interaction number fundamental interactions have reached 5 if new interactions actually in fact we don't know this standard models of particle physics of other there are no interactions, there are only these five But it is possible that that model which we are now considering and which describes everything so beautifully experimental data all phenomena which we observe in the world Perhaps still this model is not complete and then maybe some other new ones will appear forces and new interactions Well, for example, if there is something like this called supersymmetric particles To there is if there is a new symmetry in nature is new asymmetry in nature will lead to the emergence of new particles who are intermediaries between other particles will thus arise new fundamental force in nature so this is still a possibility It remains interesting that all sorts of new things interaction always leads to some new phenomenon Let's say if there were no weak ones there would be no interaction decay If there had been no decay, we would not have observed it nuclear reactions there would be no nuclear reactions the sun wouldn't shine if the sun were not there, the Earth would not be able to life could exist So here it is the presence of such interaction turned out to be it is vitally important for us that there will be no strong there would be no stable interactions there would be no atomic nuclei there would be no nuclei there would be no atoms there would be no us that is, it turned out that all the forces somehow in general, it seems like they are necessary electromagnetic interaction we we get energy from the sun these are rays Lights that come to us from the sun This is an electromagnetic interaction. if it were his Earth would be cold it turns out that all those interactions we know they are needed for something here Hex interaction with Kyiv the base provides the mass of the particle fundamental particles gain mass due to interaction with the Higgs field It's also like you can't live without it But about gravitational interaction I do not I say we would fly away from the surface planets that is, it turned out that everything interactions that exist in nature which are now open they are all vital for everything to happen we understand and know and we ourselves do everything existed A What would have happened if there had been what new interaction which yet not open Well here's another example The proton in the nucleus is stable, it is very important that it is stable otherwise it wouldn't have happened again life but experimentally the lifetime of the Proton now limited limited 10 34 degrees of years means that Generally speaking there is no prohibition so that the Proton decays but for this a new force and a new interaction are needed There are theories that predict the collapse There is a higher group of protons in them symmetries and they have new ones interactions that we don't know so much Is this a question for experiment for now? So all interactions the fundamental ones are now being built like me I already said on a single principle in this in the sense that there is such a unity of nature sometimes the question arises, is it possible? explain in some way how much interactions exist in nature That is how to understand the reason why they are like this four or why there could be 5 more there are more there are different versions how could one explain the presence a certain number of fundamental interactions such theories often are called Grand Unified Theories These theories are united by each other different types of interactions as if in this one reminds me of a tree growing there a single trunk and then it continues to branch out and you get different branches, that's the idea consists of approximately the same thing that is the single root of all interactions as if a single trunk and then as a result symmetry violations this trunk begins to branch out and several fundamental ones are formed interactions that we we observe experimentally the verification of this the hypothesis requires physics at very high energies energies that inaccessible to modern experiments will probably never be available but you can get around this problem in Finally we have an accelerator naturally this is the universe some processes leading in the Universe allow us to test these bold hypotheses that there is a single root all interactions are very different interesting task in understanding interactions in nature is to understand how Gravity is related to all other interactions Gravity stands somewhat apart Although the principle the construction of the theory is very similar to its At that time Einstein tried to build a unified the theory of gravity and electromagnetism then it seemed very real but the theory never worked out Now we a little more We know we know that there is still strong interaction weak interaction Therefore if now It seemed to build some kind of unified theory I would like to include all these others too interactions together but nevertheless there is still no such unified theory we still haven't managed to create combine Gravity with the rest interactions all interactions except gravity obeys the laws quantum physics is quantum theory all particles are quanta of a certain quantum gravity fields are not yet such exists until it can be created What is the reason that we are doing it wrong? we don't understand yet all this remains still a mystery But the quantity fundamental interactions that already openly says that it is likely some kind of unified scheme exists Symmetry plays a very important role in particle physics with the help of symmetry we classify particles with With the help of symmetry we even predict what interactions exist The point is that the known carriers of all types strong weak interactions electromagnetic is particles which are dictated by the symmetry of their sometimes called gauge fields This is due to the fact that the symmetry group elementary particle physics are called calibration groups of this group which depend on space-time point or as sometimes it is customary to say local symmetries so these local symmetries are essentially the deeds determine the whole appearance of the theory elementary particles at the same time, symmetry sometimes occurs imprecise or as we sometimes say broken what does this mean what does this mean that some exist or interactions or some terms included in the model that does not have property of symmetry or symmetry it violates the violation of symmetry in general It can be twofold This applies not only physically elementary particles are obvious violation of symmetry Well when something like that clearly falls out of symmetrical properties and it happens when in Overall, the entire system remains symmetrical. well let's say if something is described equations symmetrical equations or it's just the appearance it turns out symmetrical and some initial or the boundary conditions are not symmetries in this case it is customary to say about spontaneous disorder what does this mean more precisely? Well, let's go Let's look at this example, let's say Let's look at a bottle with a convex bottom if this bottle stands vertically table then it has symmetry rotation about the axis passing through its center in order to turn bottle nothing will change Now let's imagine that you are slightly tilt the bottle, now it's symmetrical got lost let's say we threw the bottle inside pea while the bottle was standing upright the pea got to the bottom of the bottle and we even we can't say where she is will fall because any position on the bottom of the bottle is exactly the same from the point of view of potential energy energy is equal to a pea can fall any position here we tilted the bottle the symmetry was immediately broken and the pea of course it will get to the place where it is the most low energy Imagine that we returned the bottle to its original position again the symmetry was restored but the pea is already lying in some a certain place and the very position of this peas break the symmetry here we are received an example of spontaneous violation symmetry when the whole system is still symmetrical and initial position peas another example let's imagine that we have there is some kind of magnet that located in a horizontal plane and all positions of this magnet are absolutely all positions inside the magnet are the same we are talking about symmetry with respect to isotropy relative to shifts or rotations in the plane Let's say we imposed a magnetic field inside the magnet domains were formed with a pronounced magnetic field they seem to the dipoles inside the magnet lined up this field and symmetry has already been broken the magnet is already inhomogeneous Now if we turn off the magnetic field domains will remain That is, as if in we will have a symmetrical situation conditions that violate symmetry are another example of spontaneous violation symmetries Here it would seem What does all this mean relation in particular the bottle to physics elementary particles are the most direct The fact is that the physics of amber particles there was a problem Problem was associated with the masses of all particles exact symmetry usually indicates that the particles are massless because mass members or mass if introduce into the theory they violate symmetry Photon let's say it's a massless particle what is a photon without a mass particle consequence of the phase symmetry of quantum electrodynamics Gly he particles of strong interactions also particles without mass this is a consequence symmetries of strong interactions but if there were weak interactions the symmetry was exact too carriers weak interactions would exist without massive but we know that these their carriers call them intermediate vector bosons w and Z are very even massive they have a very large mass Approximately one hundred times greater than the superior proton mass So it turns out that there is symmetry mass forbids these particles and particles possess masses Well, it would seem that it would be possible then abandon symmetry but property symmetries of weak interactions it experimentally very well verified installed from experimental data is symmetry was born then The question is how resolve this contradiction with one On the one hand the particle has mass and on the other side symmetry prohibits this mass asymmetry is correct, that was the solution found by using the mechanism which is called the spontaneous method symmetry breaking for this purpose a certain scalar field is introduced, which the potential is exactly similar in shape That very bottle I was talking about. Sometimes it is also customary to talk about potential in the shape of a Mexican hat, which is approximately the same so if you look at this the potential is of course invariant relative to rotation around the center and just like at the bottom of the bottle potential is such a lower state which is degenerate with respect to rotations and the minimum can be at any point but as soon as we give the field some classical meaning or as is customary tell particle physics give him an average value or vacuum mean value how immediately this is equivalent to what are we at lunch this bottle or this potential chose a specific position this particular provision immediately violates symmetry while the whole potential is the whole theory all equations remain symmetrical is just the case spontaneous symmetry breaking What does this give us? And this is what it gives us it turns out if we assume that the field which is a quantum the object has a classical component constantly injuries to this very thing the average value itself can be to perform a simple shift operation we let's assume that the field is equal to classical part plus quantum and here it is in this form we will substitute it into our equation and then it turns out that gauge vector bosons carriers carriers of weak interactions will acquire mass this the mass will be just proportional to this to this very average value of that classical field that we introduced Moreover, it turned out that not only carriers of weak interactions it turned out that he needed such help quarks or ptons could not have either mass if there were no symmetry discovered This is due to the fact that the theory weak interaction is left right asymmetrical That is if replace left with right that's the theory this will not change in this case electrodynamics This is not the case strong interactions Therefore, in electrodynamics in strong interactions of electrons or quarks may well have a lot of non-violations no symmetry but also quarks or ptons participate in weak interactions therefore It is necessary to maintain another mass member which is invariant with respect to and weak interactions but it is forbidden and it turns out that the introduction of that very the fields that I was talking about which are behind the account of its average value provided mass of double Z base this is the same field provides mass to the quark-electron and they all gain mass proportional to the average value of this fields this is the mechanism of spontaneous symmetry breaking was proposed at first not even a physics particle statistical physics but then migrated to particle physics and allowed so that everyone gets mass particles without breaking symmetry equations It turned out, however, that there is an underwater the pitfall is that that as was proved this theorem that If to produce something spontaneous like this symmetry breaking if you give the field the mean value is not equal to zero then theories inevitably arise massless state In particle physics this is called a theorem ties These massless states are called Galstunovsky bazons by the name of the tie who suggested it in statistical mechanics this was done Bogolyubov proved the corresponding the theorem that a massless state arises state it's all exactly the same phenomenon both in particle physics and in statistics mechanics so it turned out that you and I having solved one problem by giving mass to particles due to spontaneous symmetry breaking we created another problem we created these the most massless Galstun states which do not exist in nature, how can this be solved? the problem that has arisen It turned out that you can kill here right away two hares it turned out that there is a mechanism which even received a name by name the authors of this mechanism It is called the Higgs-Engler-Brout mechanism which showed that without mass galstunskie bosons connect to vector bosons double z-base and together form a massive particle as a result in the spectrum are completely absent without mass I remind you that we initially had the following states the doubles were without mass and Galstun bosons were massless only together as a result of unification they disappear and a single one appears massive vector particles having three degrees of freedom this is the mechanism that received experimental confirmation with discovery of the Particles that are now are called Boson Hicks because particles this was predicted in the work namely Higgs himself but the mechanism I repeat, it is named after three authors Prorots who are independent of their work this is to propose a mechanism spontaneous symmetry breaking of physics particles are used to make everything particles carriers of weak interactions Z basons as well as quarks or ptons That is all particles that participate weak interactions have acquired a mass because in case of spontaneous violation not all symmetries are broken but only the weak group is violated interactions then accordingly and acquire the mass of the particles involved weak interactions those Particles that do not participate weak interactions mass does not acquire here Photon remains without mass Glen too remains without mass in fact a problem that arose in particle physics thus the matter was resolved successfully the only thing left was to find it its confirmation in the form of discovery hiksky bazon which is what happened in 2012 year thus the mechanism of spontaneous symmetry breaking as a mechanism formation of masses of all fundamental particles was experimentally confirmed It should be noted that when we when we talk about particle masses we mean really double Z bazons quarks or we don't mean Ptons Particles which are made up of quarks, that is For example, a proton is made up of two ukvats and one dvorok so here it is the mass of the Proton is not obtained as a result of this mechanism As a result of this the mechanism turns out to be a mass of components particle of quarks and the mass of the constituent particles it is formed from the total mass components plus the binding energy in this in the sense that our world consists of massive particles most of the mass which consists simply of binding energy due to strong interactions but the original ingredients are quarks or ptons got their mass as a result spontaneous symmetry breaking [music] the last third of the 20th century was marked by the fact that it was created confirmed experimentally accepted crowned with the Nobel Prize standard model of fundamental interactions what is this First of all, it is a model that describes fundamental particles of matter and all their interaction model this is model of quantum field theory and is formulated as a Lagrangian quantum field theories This means that a theory that is described as quantum mechanics fields whose quanta are elementary particle I includes all fundamental particles of matter There are not so many of these particles, that's six quarks and 6 Lipton They participate in three types fundamental interactions strong weak and electromagnetic gravitational interaction in this in this case we ignore the forces of its smallness and it is not included in the standard model So there are three types of interactions and 6 types particles the standard model has a structure that is structure is usually associated with groups symmetries Three types of interaction Three groups Symmetry all these groups belong to to the same class it is so called unitary groups electromagnetic interactions symmetry groups o1 are described unitary group with one parameter and respectively one carrier particle electromagnetic interactions are Photon weak interactions have a symmetry group so2 there are already three parameters here and accordingly there are three particles the carrier of weak interactions is w and z-bazon strong interactions are described group su3 here already 8 parameters and respectively 8 carrier fields interactions they are called galleons that's what concerns interaction carriers the particles of matter themselves also belong to representations of symmetry groups from the point of view of the strong group interactions A and only those involved in them quarks quarks act as standard triplet models that is, they have quantum numbers acquiring three meanings often this call the color by the word blue red green weak interactions all particles appear as doublets this is also a lower representation representation of the weak symmetry group interactions We have up and down quarks. electron and nitrine are examples of two doublets I wonder what quarks or ptons are repeat each other This is called generations there is the first generation the second generation And the third generation of standard models Generally speaking it's not very clear why nature chose three generations There is the first generation of particles of which the entire observable world is a copy the second generation is the third copy of this third generation standard model includes three generations these particles are fundamental in the sense that we don't see any structure in these particles Generally speaking, it is an absolute statement it can't be done because earlier we will say about that it also seemed particles without structure and then this the structure was discovered so it is impossible say that those Particles that we are now we consider non-structural to be such forever maybe in the future something will happen to us it will be revealed that it is unknown now but on today those Particles that make up the standard model is structureless particles point particles these quarks or ptons as I already said they are represented as point particles standard model if we want to describe some process occurring in nature usually in them It is not the quarks themselves that participate, but the particles are made up of quarks, that is, hadrons leptons are electron-mion taon still observed in the form of free particles or interacting particles in nature therefore processes that they are described with leptons are directly described by the standard model with drones indirectly as I already said but nevertheless, one way or another, any interactions and any transformations which we observe in nature both on both at short and long distances distances describe standard models in this sense the standard model is the crowning glory The whole building of elementary physics particles and in a sense the whole building fundamental physics because describes the most fundamental laws of nature which are known today What properties do particles have? included in the standard model But first In general, we are used to describing quantum the world with the help of so-called quantum An example of a quantum number is electric charge electric charge this is the characteristic of the Particles that we It's clear particles are positively charged negatively charged not at all charged and electric charge is actually quantum number that is conserved in conservation of electric charge in nature The standard model describes the corresponding symmetry groups from symmetry of the theory should be preserved electric charge but it is not the only characteristic of particles since as is known standard The model has three symmetry groups strong interactions describe color objects color of course concepts are conditional just a quantum number that acquires three meanings conveniently to indicate the color for clarity like this the color charge also has a group symmetry and also conserved value the color charge of quarks is conserved weak interactions have their own charge it is called a little left isospin a complex name with a historical origin the reason but this is also a characteristic weak interaction is also a charge which is thus preserved all particles have quantum numbers or have quantum charges that are conserved as follows from the symmetry of the standard models the standard model has properties that at first glance it's not very clear Well for example when we talk about quarks we we say that quarks cannot be observed in in a free state that is, we are so confident that quarks exist inside hadrons that the fact that we can't directly It doesn't seem to us to watch anymore Weird But properties that particles have very can be easily verified experimentally therefore, we confirm this experimentally all the properties of the standard model are there characteristics that are not obvious Well For example the standard model describes the masses particles and it describes the transitions of some one type of particles and others at the same time maintaining the necessary symmetry Well, here it is interesting example of weak interaction in which a series violation occurs symmetry in particular violation spatial parity or to solve charge conjugation when the particle replaced by anti-clean what else is included in the standard model in addition to quarks or optones standard model included hicks base Hicks's Boson arose in theory because the reason that it was necessary to find a mechanism which would give mass to all particles standard model This was achieved by spontaneous symmetry breaking by introducing additional theory scalar fields, that is, possessing spinal 0 which was named hicksovsky bazan thus full composition The fields of the standard model consist of six quarks six leptons one Hicks boson and carriers of all three types of interactions all these particles the latest ones have been experimentally discovered the discovered particle was the Hicks Boson which was opened in 2012 all the rest were discovered in the 20th century The last to be discovered was the neutrino It's called taone3 on 3 nitrines but it was opened in 2000 thus the 20th century completed the standard model excluding the Hicks boson and all particles experimentally confirmed the question arises does the story end here or maybe there are some other Particles which have not yet been included in the standard model but they will have to enter there or maybe there is something completely other which is not described standard model to all these questions there are different answers we don't know the truth yet But first of all, if we talk about new ones particles such as new quarks and new leptons that have not yet been discovered like me I already said there are three standard models generations of these particles The question is: Is there is the fourth one yet Experimental fourth generation it is not visible, moreover, there are indirect ones data How is it related to experiments particle physics and cosmology that maybe the fourth generation and no case in that the standard model is so called quar-klipton symmetry how many quarks so many or ptons And here naleptones More precisely, there are nitrines limitations from cosmology that quantity independent along the trine line is equal to 3 there there is a small loophole for 4 but throughout it is likely that it will also be closed soon so if the number is not three it is equal to 3 quark krypton symmetry then and number generations of all other parts are equal three And thus we have completed this plan standard model Hicks Boson I said that he only one can there be two or four or more too, the answer is probably the same There may be other Hicks ones bosons We may have only discovered them so far one but the theory allows the presence a large number of rural Bazany if they are or not This is a question for an experiment in this sense can be like this it turns out that the standard model is not yet completed, more will be opened particles but there may not be one boson is enough to give mass to all particles new interaction we talked about three types of interaction which are all included in the standard model are not implemented as carrier exchanges gauge fields with spins of units In a sense, the Hicksian Boson can be considered as a carrier fourth interaction when he acts as a carrier of interaction with spin zero But if there is no spin yet some new interactions or some new symmetry groups more wider than the standard model does not fit non-standard model as a component into some more general theory This is a question also open it is excluded that this is not so it is possible that it is part of a more general one theory but it is not visible yet I must say that when we talk about that what is the standard model Triumphal ended we are talking about the fact that everything is without exceptions experiments that are being conducted but accelerators in underground physics in in space they are all brilliantly perfect with enviable precision, sometimes up to 10-10 characters describe the standard model in this sense It is absolutely a unique model that allows describe a huge part of nature that is inanimate nature with the help of very simple universal mathematical standard model hold of fundamental interactions that may already be now we need to call it standard theory fundamental interactions can create the impression that all the problems solved However, of course it is not so was boring If they were all solved What problems remained but before all that remains are problems within itself models because there are many left questions like Why and secondly, some phenomena remained nature which in all probability go beyond the standard model or maybe we're just not very good yet we understand well how they need to be explained It is true that all these phenomena nature here are the ones that require explanation really go a little beyond the scope particle physicists they are in Mostly they came to us recently from cosmology the problems of elementary physics proper particles They are described perfectly standard model but many remained questions why Well let's start with questions Why Why are there three generations of standard particles? models Why did nature need two copies of the generation it consists of the whole world around us Once upon a time we thought that these generations there just aren't those particles that we have we observe this and there are Elementary particles but then it turned out that there were none in Cosmic rays and accelerators for some reason copies are born, that means the question Why do we need three copies of the world that we we are observing another question we have three types of interactions Why did nature need three species? interactions Why three and Why these three were needed Of course, you can answer this question. based on the so-called anthropic principle, that is to say so that humanity lived needed these three types interactions are really correct That's right, because let's say we are energy We get it from the sun, as you know it is brought to us by the sun's rays is nothing more than electromagnetic interaction we walk on earth attracted to it by the force of gravity there is a gravitational interaction this fourthly, we also need it We are made up of atoms from within an atom there is an atomic nucleus protons neutrons would have flown apart in different directions if something didn't hold it back it's strong interaction means what the [ __ ] atoms what there were bodies so that we could be with you we need strongly interact weakly interaction it is responsible for disintegration It would seem that why do we need it it took no for that the sun was shining there are thermonuclear reactions and thermonuclear reactions are decay processes are weak interaction That is, if it were not for weak interaction would not shine the sun and that's it, that's all interactions that we have with you needed but the question is, maybe they are different maybe we don't understand everything yet we don't see everything einstein once dreamed it was then impossible to create a unified theory electromagnetic interaction is known And he tried to create gravity a unified theory of electromagnetism and gravity but as we know it didn't work out Now we know that there are still weak ones electromagnetic means it's time to create unified theory of three interactions included in the standard model and gravity Is there such a single theory? There are many. There is even a name for different ideas: theory The Great Unification that unites strong weak electromagnetic interaction Is this theory correct? or not we still don't know there are theories that combine both Gravity too these theories are even more interesting complex, even more incomprehensible, sometimes even use words like theory of everything there is a string theory which is a kind of generalization of quantum field theory to extended objects at some point claimed to build such there is no unified theory of everything yet either it worked out But it is possible that we just haven't found the right wording yet So going beyond the standard introductions may be required some interesting new solutions which will allow us to build a generalization what we now understand and know but there are problems that already exist probably require some new theory these problems come to us from cosmology The fact is that cosmology is already is related to particle physics because as it turned out, that something what happened in the early universe predetermined the development of the Universe describes in essence the physics elementary particles so here is one of the problems that came to We have a very good problem from cosmology and brought Now many say this dark matter problem It follows from cosmology that in addition to the usual matter that we observe, that is, this stars Galaxy Star dust and so on furthermore there is another matter which does not emit Light which electrically neutral it is called dark matter and now looking back at the standard model fundamental interactions we must answer the question of where from where did dark matter come from? What particles does it come from? it can consist It seems that there is no standard model. a suitable candidate for this role. This so what if dark matter described by a particle which is very likely then this is some new particle that in our standard set does not include this the mystery is yet to be solved and found find such a particle experimentally find a theoretical explanation for this particles another problem that came to us from cosmology in the early universe were born equally particles antiparticles That is, if later hydrogen should have formed, let's say antihydrogen will form if helium then antihelium if there is iron then Anti iron and everything would be equal but as we know if particles antiparticles when they meet, they turn into pure energy That is, light This means that if there were in the world sufficient amount of matter antimatter from time to time they would collided and highlighted what not moreover, it is not observed at all we observe antimatter we observe only the matter of the visible part in the village a natural question arises What where did that come from called the stormy asymmetry of the Universe what we see baryons and don't see anti-barevatov this is a problem in the standard model fundamental interactions in general saying it is solved it is solved at the expense of so so-called combined disorder parity due to some parameter called the phase which is responsible for the CP violation and also for the drilling asymmetry of the Universe but the mechanism stormy asymmetry of the Universe to this day I don't understand this remains a mystery Although everyone it's clear that somehow it should be explained differently our universe is not would exist in the form in which it is exists now there are simpler questions to which I haven't found an answer yet either, for example mysterious particles of neutrinos which many people are into it She is mysterious mainly because which is very difficult to register like that here is the nature of this particle, it is also not up to the end is not yet clear and the mass of this particle is still unknown and although we have everything tools to describe this particle of the standard model but Still, she remains a bit mysterious for us most likely experiments the next few years will allow this mystery to be solved end to resolve and we will definitely understand what kind of particle is nitrine? What is its mass is it an antiparticle to itself or not and in this meaning our understanding of the standard model in this aspect it will be completed There is still one riddle can be the most difficult the problem that we are currently facing is description of particle physics and cosmology too this is a related problem It was named dark energy. what is this the thing is that the world around us filled with mateia and can be counted the amount of this matter and it turns out that the amount of matter determines the curvature of space in in which we live if the density of matter equal to the critical space is flat if the energy density the space is too small is open reminds let's say the saddle has negative curvature if energy density above critical then the space is closed it resembles the Sphere so all the substance we measure is in The Universe If you add it all up it gives the density is noticeably lower critical that would tell us that we live in an open world but there is also dark matter From cosmological data it follows that dark matter is about 4 times larger than ordinary matter means we add ordinary observables dark matter the matter still lacks density for critical it still works out about 30 percent It would seem that we live in the open in the world but no it is possible to measure the curvature space and bring it to produce it's the same way How can you say we do at school can measure the amount angles of a triangle It is known that in Euclidean geometry in flat geometry the sum of the angles of a triangle is 180 degrees if we are on a sphere then the sum the angles of the triangle will be more than 180 degrees if we are in the saddle then the sum of the angles will be less than 180 degrees is there to find out what is the curvature of our world it is possible if you measure the sum of the angles triangle only triangle should to be very big you need to somehow spread out the vertex points of the triangle are in different the ends of the universe and now imagine what is the experiment was done and the sum of the angles of a triangle was measured this is due to the change in the so-called relic microwave radiation and that's when it was measured it was discovered that the sum of the angles of a triangle is equal to approximately 180 degrees That is, this means that we live approximately in flat world then the question is what is the remaining 70 percent density That's it They call it dark energy, it's some kind of a substance we don't know anything about yet we know but it requires an explanation explanations for the presence of this substance C what it consists of, how it is described and why is 70 percent often a substance describe the so-called cosmological constant in Einstein's equation Einstein was leading this cosmological constant This is not the only thing explanation existing dark energy but such quite naturally I would say so in order to describe the required quantity dark energy to get these 70 percent This is the very thing the cosmological constant must have certain values it turns out that it is that it is approximately 100 orders of magnitude values are less than we would expect that is, we became as if naively we would be wrong to calculate this value 100 orders of magnitude full of disasters this may be the most important mystery which is now, it is as if fundamental physics and as soon as particle physics claims to be the role of fundamental physics describing all natural phenomena together with gravity then this is the riddle of elementary physics particles cosmology gravity theories a single theory all of them together must this solve the riddle and solve this problem while she remains the main unresolved problem of fundamental physics