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Gödel and the unreality of time

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Re: Gödel and the unreality of time

#21

Post by Nursie »

announcerman wrote: post #20
Schiphol wrote: post #13

Folks are asking about the practical import of time not passing---if indeed it does not. I know of this rather substantial one: my fear of death, and I guess that of other people too, depends on the notion that my own annihilation in time, and that of everything I care about, is absolute and definitive. Existence no longer has me as one of its inhabitants, and that's that. This picture is in its turn grounded on a pr…

How do you decide that your new view is valid and is not based on your need to lessen the fear of death. I have problems with this with every new thing I try to use to make death more palatable, be it religion, philosophy or anything else. I just cannot believe in anything because I feel its just a convenient way to make the fear smaller. How can any view be valid if its based on self interest?

I find it weirdly comforting to know that nothing in this universe is really eternal. If you could live literally forever, you'd witness the end of all life on earth in about a billion years, and eventually the slow heat death of the universe.

I'd love a lot more life than I have in front of me - a few millenia at least - but even with a traditional, linear view of time there's no point, need or possibility of eternity.

Re: Gödel and the unreality of time

#22

Post by navaati »

Schiphol wrote: post #13

Folks are asking about the practical import of time not passing---if indeed it does not. I know of this rather substantial one: my fear of death, and I guess that of other people too, depends on the notion that my own annihilation in time, and that of everything I care about, is absolute and definitive. Existence no longer has me as one of its inhabitants, and that's that. This picture is in its turn grounded on a pr…

> all of the moments that make me and everything I care about are still there, occupying their own spacetime regions, eternal, in a way.

Yes but not evolving anymore. What sucks isn't really not existing anymore, what do sucks is having no future. If a supervillain's evil plan was eternally freezing the universe right now, I would be as sad as if it was making it disappear.

Re: Gödel and the unreality of time

#23

Post by nabla9 »

cousin_it wrote: post #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?

Of course it's must deeper than that.

http://kurtgoedel.de/cms-83FO/wp-content/uploads/2016/10/Goe...

It's a solution allowed by GTR, not a new trick definition. It belongs to the family of 'dust solutions'. You arrange particles (can be as big as galaxies) that move in certain way and you get time travel. Only other assumption is nonzero cosmological constant.

You can't get time travel in Newtonian universe just by arranging objects in it to move certain way.

In general, closed timelike curves are allowed in GTR. It's possible generate them several different ways. Gödel just made super elegant one. What GTR allows and what actually is allowed are different matters. Just like Newtons equations break at some extremes, same probably happens to GTR.

Re: Gödel and the unreality of time

#24

Post by Schiphol »

announcerman wrote: post #20
Schiphol wrote: post #13

Folks are asking about the practical import of time not passing---if indeed it does not. I know of this rather substantial one: my fear of death, and I guess that of other people too, depends on the notion that my own annihilation in time, and that of everything I care about, is absolute and definitive. Existence no longer has me as one of its inhabitants, and that's that. This picture is in its turn grounded on a pr…

How do you decide that your new view is valid and is not based on your need to lessen the fear of death. I have problems with this with every new thing I try to use to make death more palatable, be it religion, philosophy or anything else. I just cannot believe in anything because I feel its just a convenient way to make the fear smaller. How can any view be valid if its based on self interest?

In this case the view in question (the B-theory of time) is supposed to be backed up by science: e.g., the Gödelian models in the OP, but, much more than that, the relativity of simultaneity. The RoS is really non-negotiable, and still entails that the actual world does not have a Newtonian absolute present.

Re: Gödel and the unreality of time

#25

Post by SiempreViernes »

navaati wrote: post #22
Schiphol wrote: post #13

Folks are asking about the practical import of time not passing---if indeed it does not. I know of this rather substantial one: my fear of death, and I guess that of other people too, depends on the notion that my own annihilation in time, and that of everything I care about, is absolute and definitive. Existence no longer has me as one of its inhabitants, and that's that. This picture is in its turn grounded on a pr…

> all of the moments that make me and everything I care about are still there, occupying their own spacetime regions, eternal, in a way. Yes but not evolving anymore. What sucks isn't really not existing anymore, what do sucks is having no future. If a supervillain's evil plan was eternally freezing the universe right now, I would be as sad as if it was making it disappear.

The block universe doesn't mean a specific moment in time is all that is, it means that they all coexist.

Dynamics in block universe is like reading a book: it seems things happen as you move your attention over the pages, but in truth the story was fixed before you even started.

Re: Gödel and the unreality of time

#26

Post by cousin_it »

nabla9 wrote: post #23
cousin_it wrote: post #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?

Of course it's must deeper than that. http://kurtgoedel.de/cms-83FO/wp-content/uploads/2016/10/Goe... It's a solution allowed by GTR, not a new trick definition. It belongs to the family of 'dust solutions'. You arrange particles (can be as big as galaxies) that move in certain way and you get time travel. Only other assumption is nonzero cosmological constant. You can't get time travel in Newtonian universe just by…

I see. Thanks for the link!

Re: Gödel and the unreality of time

#28

Post by AnIdiotOnTheNet »

Schiphol wrote: post #13

Folks are asking about the practical import of time not passing---if indeed it does not. I know of this rather substantial one: my fear of death, and I guess that of other people too, depends on the notion that my own annihilation in time, and that of everything I care about, is absolute and definitive. Existence no longer has me as one of its inhabitants, and that's that. This picture is in its turn grounded on a pr…

There's a better way to look at your mortality, I think, which is to realize that your conception of self is flawed. Try this as an exercise: determine precisely which part of you is "you", the part that if it were to change or cease to exist would make you a different person. What you'll find is that there isn't one. Every part of what you are has changed and evolved over time. Then ask yourself why it is that people are often willing to die for their family, community, nation, or even ideology.

Re: Gödel and the unreality of time

#29

Post by AnIdiotOnTheNet »

Nursie wrote: post #21
announcerman wrote: post #20

Earlier quoted context omitted.

How do you decide that your new view is valid and is not based on your need to lessen the fear of death. I have problems with this with every new thing I try to use to make death more palatable, be it religion, philosophy or anything else. I just cannot believe in anything because I feel its just a convenient way to make the fear smaller. How can any view be valid if its based on self interest?

I find it weirdly comforting to know that nothing in this universe is really eternal. If you could live literally forever, you'd witness the end of all life on earth in about a billion years, and eventually the slow heat death of the universe. I'd love a lot more life than I have in front of me - a few millenia at least - but even with a traditional, linear view of time there's no point, need or possibility of eterni…

Even if the universe were eternal, the way I see it eternity is just another kind of ending. I think the important thing to realize is that a thing does not cease to have value simply because it is impermanent.
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