B Free Will & Relativity: A Thought Experiment

CactusLand
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I watched a documentary by Brian Greene, "The Illusion of Time" a few weeks ago, and a question has been bothering me ever since. In the documentary he explains that an alien, traveling toward the earth, would see into our future. So here is my question.

The second half of a college football game is just getting underway, the score is 0-0, so there is about 1.5 hours left till the game finishes. I am in the stands, watching with a friend and put my beer to my lips, at the same moment, from space, an alien traveling at a high speed towards the Earth peers out of his super duper telescope and looks at the scoreboard, and sees the last second tick off the clock, and the final score, Notre Dame 7 - USC 3.

Questions:

1. Is it possible for the alien to look, and I to sip, simultaneously?

2. If we can act simultaneously, could the alien theoretically see the final score while I was still sipping my beer with 14:59 left in the 3rd quarter?

3. If 1 & 2 are possible, and leaving the multi-verse aside for the moment, is Notre Dame 7 - USC 3 the only possible outcome of the game?

4. Well, seems obvious...where is free will in all of this, or is it simply an illusion?

Thank you in advance for your thoughts.
 
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CactusLand said:
I watched a documentary by Brian Greene, "The Illusion of Time" a few weeks ago, and a question has been bothering me ever since. In the documentary he explains that an alien, traveling toward the earth, would see into our future.

That's essenially nonsense. Just Mr Greene trying to be clever.

If you would like to learn the basics of relativity you will need a little maths and some time and effort.
 
Is there some danger thinking about string theory for a good phycisist's mind or is it rather getting involved in writing popular-pseudoscience textbooks and TV-movie scripts? SCNR.
 
@CactusLand, as the previous two replies suggest, Brian Greene's popularizations are loathed and despised not especially well-regarded by those of us who value accurate layman-friendly explanations of this stuff. I don't think there is a better answer to your question than "Write off the hour you wasted on that documentary, spend some time trying to learn the real thing".

Special relativity is one of the most fun and fascinating pieces of human knowledge, and (unusual for much of modern physics) it can be understood with only high school math - the hard part is retraining your intuition to understand what the math is telling you. Get hold of a decent textbook, spend some time with it, come back here as soon as you get stuck and we will gladly talk you through the sticking points.

One of my personal favorites is Taylor and Wheeler's "Spacetime Physics". You might also try "Relativity for poets", by our own @bcrowell, and others will have their suggestions. As a standalone exercise, you could google for "Einstein train simultaneity" to see Einstein's classic thought experiment demonstrating the relativity of simultaneity - if you can understand that, the rest of special relativity proceeds logically.

In the meantime, we can close this thread. Start a new one as soon as you need us.
 
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