Lee Smolin's "Time Reborn" and the Andromeda Paradox

[Gemini]

I haven't read the book, just a review of it on Sean Carroll's blog. What I'm wondering is how you can reconcile the view of time he argues for with the Andromeda Paradox. I'm sure he knows his stuff, I just don't know how what he's proposing would work.

[Alex K]

Can you quickly summarize what the conflict is in your opinion?

[Aoi Magi]

I read the link
Didn't understand a thing
Need explanation for dummies please

[Gemini]

Can you quickly summarize what the conflict is in your opinion?

It sounds like instead of a four-dimensional, block universe in which the arrow of time is a result of entropy increasing from a low-entropy state, he's arguing for something like presentism. This is from a blurb on the book: "[Smolin] finds that contemporary physics eliminates time. He argues persuasively that any adequate cosmology rests on making time and “NOW” fundamental. Here laws evolve in one universe, and the future is open to unknowable novelty." --Stuart Kauffman

I thought that was incompatible with relativity. According to the Andromeda paradox, the "now" over in the Andromeda galaxy will be different for someone on earth and someone in orbit. I don't see how that could be if there's just one evolving "now."

[Alex K]

Can you quickly summarize what the conflict is in your opinion?

It sounds like instead of a four-dimensional, block universe in which the arrow of time is a result of entropy increasing from a low-entropy state, he's arguing for something like presentism. This is from a blurb on the book: "[Smolin] finds that contemporary physics eliminates time. He argues persuasively that any adequate cosmology rests on making time and “NOW” fundamental. Here laws evolve in one universe, and the future is open to unknowable novelty." --Stuart Kauffman

I thought that was incompatible with relativity. According to the Andromeda paradox, the "now" over in the Andromeda galaxy will be different for someone on earth and someone in orbit. I don't see how that could be if there's just one evolving "now."

Hmmm. I'm sceptical about this entire discussion if it doesn't yield anything testable (and I don't see how it does) - it might just be a discussion of formalism. Does my "now" on Andromeda already exist or not? What does that even mean? What does it mean for the future to exist already, or not.... I can't help but think that the entire discussion might be about something that isn't clearly defined.

[Gemini]

Hmmm. I'm sceptical about this entire discussion if it doesn't yield anything testable (and I don't see how it does) - it might just be a discussion of formalism. Does my "now" on Andromeda already exist or not? What does that even mean? What does it mean for the future to exist already, or not.... I can't help but think that the entire discussion might be about something that isn't clearly defined.

That does make more sense to me than the Andromeda paradox. It leaves me wondering how physics constrains our understanding of time though. Given relativity, would it be possible in principle for there to be an omnipresent being (like God) who is simultaneously experiencing events that are occurring in distant galaxies?

[Alex K]

Hmmm. I'm sceptical about this entire discussion if it doesn't yield anything testable (and I don't see how it does) - it might just be a discussion of formalism. Does my "now" on Andromeda already exist or not? What does that even mean? What does it mean for the future to exist already, or not.... I can't help but think that the entire discussion might be about something that isn't clearly defined.

That does make more sense to me than the Andromeda paradox. It leaves me wondering how physics constrains our understanding of time though. Given relativity, would it be possible in principle for there to be an omnipresent being (like God) who is simultaneously experiencing events that are occurring in distant galaxies?

Yes, sure.

[Gemini]

That does make more sense to me than the Andromeda paradox. It leaves me wondering how physics constrains our understanding of time though. Given relativity, would it be possible in principle for there to be an omnipresent being (like God) who is simultaneously experiencing events that are occurring in distant galaxies?

Yes, sure.

Thanks for answering this for me, by the way. It's been nagging at me for three years now...

[The Grand Nudger]

That does make more sense to me than the Andromeda paradox. It leaves me wondering how physics constrains our understanding of time though. Given relativity, would it be possible in principle for there to be an omnipresent being (like God) who is simultaneously experiencing events that are occurring in distant galaxies?

Yes, sure.

Nope.  Might seem like a minor nitpick, but it;s actually pretty relevant...even a -omnipresent- being would have to contend with distance.  So some part of it is experiencing a in y...and another is experiencing b in z...but internally, these two experiences cannot be maintained concurrently..if...for no other reason...than the time it takes a signal  (like a brain wave - or light) to travel between whatever part of it is in y and whatever part of it is in z. Omipresence is silly but a "not even wrong" proposition, omni-experientialism- so far as we can tell-...is demonstrably impossible.

[Alex K]

Yes, sure.

Nope.  Might seem like a minor nitpick, but it;s actually pretty relevant...even a -omnipresent- being would have to contend with distance.  So some part of it is experiencing a in y...and another is experiencing b in z...but internally, these two experiences cannot be maintained concurrently..if...for no other reason...than the time it takes a signal  (like a brain wave - or light) to travel between whatever part of it is in y and whatever part of it is in z. Omipresence is silly but a "not even wrong" proposition, omni-experientialism- so far as we can tell-...is demonstrably impossible.

If you insist on a being which is bound in its actions and perception to the limitations matter experiences within the spacetime.