Understanding the Andromeda Paradox

Apr 29, 2025

Lecture on the Andromeda Paradox by Hakeim Olusi

Overview

  • Andromeda Paradox: A concept in Einstein's relativity.
  • Origin: Introduced by Roger Penrose in "The Emperor's New Mind" (1989).
  • Basic Idea: When two people observe Andromeda, they can see events days apart due to differences in motion and perception of time.

Key Concepts

Relativity and Perception of Time

  • Simultaneity: Motion affects how events are perceived in time.
  • Observers: A stationary observer sees events differently than a moving one.
  • Penrose's Explanation: Two people passing each other may perceive Andromeda events (like a space fleet launch) at different times.
  • Subjectivity of Now: What is "now" varies for different observers.

Space-Time Diagram Explanation

  • Axes: Space (horizontal) and Time (vertical).
  • Movement: Stationary observer moves vertically, a moving observer has a slanted path.
  • Light Path: Travels at a 45-degree angle.
  • Simultaneity: Events happening on the same horizontal line are simultaneous for an observer.
  • Disagreement: Moving observer sees simultaneous events differently due to motion.

Penrose's Interpretation

  • Future and Decisions: As the observers meet, one perceives a decision (e.g., a fleet launch) as occurring, while the other sees it as undecided.
  • No Immediate Knowledge: Observers cannot know the Andromeda events immediately.
  • Question of Fate: Raises the question if the future is open or predetermined.

Philosophical Implications

  • Block Universe: Suggests the future is as fixed as the past.
  • Alternative View: Some argue against discussing simultaneous events elsewhere, but this contradicts common usage of "now."

Conclusion

  • Relativity's Complexity: Even experts find relativity perplexing.
  • Broader Fascination: Physics, including quantum mechanics, reveals profound truths about the universe.

Study Resources

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  • Recommended Courses: Quantum mechanics, quantum computing, differential equations.

This lecture provides a deep dive into the Andromeda paradox and its implications in the theory of relativity, emphasizing the subjective nature of simultaneity and the philosophical question of a predetermined universe.

Full transcript