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Gödel and the unreality of time

edwardfeser.blogspot.com

1–10 of 132 posts

Re: Gödel and the unreality of time

#2
OK, so tldr: If you can't define a partial ordering between events (ie. "earlier than" as in A can cause B, "later than" as in A can be caused by B, "same time" as in there can be no causal relationship between A and B), then time as defined in B-theory can't exist.

So what? What are the consequences?

Re: Gödel and the unreality of time

#4
post #2

OK, so tldr: If you can't define a partial ordering between events (ie. "earlier than" as in A can cause B, "later than" as in A can be caused by B, "same time" as in there can be no causal relationship between A and B), then time as defined in B-theory can't exist. So what? What are the consequences?

Nothing! It's fun thinking about it.

I think, he's trying to say that "time" is really not a thing, but rather our perception and understanding of time makes it a thing. What we should see as time is actually some flow of causality. You cannot map "earlier/later than" or "same time" to causal reality, those qualities only refer to time as a scale, not as a natural occurrence of causality order. Or so I think.

Re: Gödel and the unreality of time

#5
post #2

OK, so tldr: If you can't define a partial ordering between events (ie. "earlier than" as in A can cause B, "later than" as in A can be caused by B, "same time" as in there can be no causal relationship between A and B), then time as defined in B-theory can't exist. So what? What are the consequences?

From the article, "[this] casts doubt on the reality of time in our world".

If the order is undefined, then how can you say I'm late?

Re: Gödel and the unreality of time

#9
post #2

OK, so tldr: If you can't define a partial ordering between events (ie. "earlier than" as in A can cause B, "later than" as in A can be caused by B, "same time" as in there can be no causal relationship between A and B), then time as defined in B-theory can't exist. So what? What are the consequences?

If there is no way to define an unambiguous time ordering, then you cannot use a "flow" of time picture to describe time. In other words, despite the everyday perception of time as something that marches ever onward, in reality we live in a "block" universe where nothing moves.

Or so was supposedly Gödel's argument.

Re: Gödel and the unreality of time

#10
You can just as easily have a Newtonian space with time travel (roll up the time coordinate in a circle by identifying T=0 with T=1). I think the same trivial construction would work in GR, so you don't need mass, rotation, etc. That doesn't seem to prove anything about the nature of time. Does anyone have a copy of Gödel's article so we can see if the argument goes deeper?
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