[Topgun]

An infinite universe (or infinite universes, either coexisting or causing one another), either infinite in a chronological sense or infinite in a volumetric sense would violate the second law of thermodynamics!

Im sure someone else conducted the same thought experiments and figured this out already but OMG, I just figured something out by myself!

[General Battuta]

why

No process is possible whose sole result is the transfer of heat from a cooler to a hotter body.

I see no violation.

[Topgun]

Basically this:
A wasteful body cannot be eternal. If it is eternal, it cannot be wasteful.

Ill explain it more in a bit, brb.

[redsniper]

Hence, heat death. The universe is not eternal.

[General Battuta]

Basically this:
A wasteful body cannot be eternal. If it is eternal, it cannot be wasteful.

Ill explain it more in a bit, brb.

This does not contradict a spatially or temporally infinite universe, it merely implies heat death, which has been known for heap long time.

[Topgun]

Hence, heat death. The universe is not eternal.

well, duh. But it also means that the universe had a beginning and that beginning was the beginning of everything, there was no "before the big bang" as that would mean singularities could be created and that violates thermodynamics. Anyway, expect a bigger post.

[Flipside]

It gets wierd because the Law of Thermodynamics deals with the Universe as it is now, that law may not always have worked in quite the same way, or at all.

Take a watch of this:

http://www.youtube.com/watch?v=_bGx3UB-Slg

[General Battuta]

Hence, heat death. The universe is not eternal.

well, duh. But it also means that the universe had a beginning and that beginning was the beginning of everything, there was no "before the big bang" as that would mean singularities could be created and that violates thermodynamics. Anyway, expect a bigger post.

The big bang was the beginning of time and space. What happened 'before' it, in any sense that that matters, is still kind of problematic for us to figure out, though some ToEs have suggestions. M-brane theory is one example.

[qazwsx]

Urgh, speaking of philosophical discoveries, I'm just tired enough to consider posting this a good idea:

If the many-worlds interpretation is correct, and every possible alternate outcome to a quantum event is real, then that's OK. However, if "real world" events can be affected by this, (simplest example: Schrödinger's cat, splits into 2 "worlds" 1 with a dead cat, one with a live cat) and if (BIG IF) all real world events are in fact governed by this, then this argument follows:

if any of these near-infinite "me"s are to die, then those "me"s would be unable to know if they were alive or dead because, well, they'd be dead.
From this, I can assume that if I enter any life threatening condition in which there is a chance of success, no matter how slim, a universe should "branch off" with me surviving in it. As in a universe in which I am dead, I am unable to tell I'm dead, I will only be aware of the universe in which I am alive. Until I arrive upon a situation which is impossible to survive, even at the longest odds, I should I theory, be immortal from my perspective.

I mean, I don't take this seriously, and I reckon I've gone wrong somewhere, but felt like posting it anyway :\

[General Battuta]

It's called quantum immortality. Been floating around for a while.

Unfortunately many-worlds is one of those things that's...more fun than meaningful, especially as it relies on a bit of an overzealous extension of quantum effects to the macro scale. For example, there is no probability worth considering that that bomb WON'T fall on your head; the probabilistic events are confined - in terms of being significant, at least - to the individual particles in the bomb.

[Ghostavo]

I seem to remember reading something that said basically that there is no apparent reason why we should "see" time moving the way it does and that the increase in entropy is what we use as a reference for the passage of time.

[Topgun]

alright, im back.

I assume these to be true:
There is no such thing as random, if a result appears random it is do to unknown variables.
The Universe is a closed system.
Order can't be created, only destroyed (another way to say the second law of thermodynamics applied to a closed universe)
The universe came from a point (the singularity) then exploded.

So lets start from the beginning. The universe right now is a point and BAM, its not. great. What caused it to explode? well lets say that the universe follows a cycle, that the universe exploded and soon will implode only to start the whole thing again, basically that the universe is infinite temporally. This must mean that time works in cycles because the universe would be the same every time it exploded, just like a pendulum would always return to the same spot if there was no friction. This violates the second law, every time the universe implodes it would have less order than the last time. It also goes against the little evidence that we have, as the universe seems to be expanding so fast that it will never begin to implode.
This means that the universe doesn't cycle and that time had a beginning.

[General Battuta]

There is no such thing as random, if a result appears random it is do to unknown variables.

Hidden variables explanation of QM was disproved last century, though.

So lets start from the beginning. The universe right now is a point and BAM, its not. great. What caused it to explode? well lets say that the universe follows a cycle, that the universe exploded and soon will implode only to start the whole thing again, basically that the universe is infinite temporally. This must mean that time works in cycles because the universe would be the same every time it exploded, just like a pendulum would always return to the same spot if there was no friction. This violates the second law, every time the universe implodes it would have less order than the last time. It also goes against the little evidence that we have, as the universe seems to be expanding so fast that it will never begin to implode.
This means that the universe doesn't cycle and that time had a beginning.

This is just a fantasy, though - the cyclic model of the universe is not currently supported by cosmological data. Current cosmology suggests a spatially infinite, flat, open accelerating universe. It will never contract into a singularity again.

Time can have a beginning and still be infinite.

[Topgun]

Heat death isn't the end of the universe?

[StarSlayer]

Hence, heat death. The universe is not eternal.

well, duh. But it also means that the universe had a beginning and that beginning was the beginning of everything, there was no "before the big bang" as that would mean singularities could be created and that violates thermodynamics. Anyway, expect a bigger post.

The big bang was the beginning of time and space. What happened 'before' it, in any sense that that matters, is still kind of problematic for us to figure out, though some ToEs have suggestions. M-brane theory is one example.

Assuming this is the production environment, I assume UAT immediately preceded the Big Bang.

[General Battuta]

Heat death isn't the end of the universe?

No. Things merely get very boring and increasingly entropic.

[redsniper]

Yeah, heat death is just when all reactions have played out, all the stars have gone cold, and so on. All that's left is dust and echoes...

[Flipside]

Though, from what I recall, even that theory is somewhat in flux, it requires the Universe to break down into a 'smooth paste', which may not actually be possible. I think that's why Gravity is the centre of some very searching questions at the moment, since it seems to be the trigger that creates everything, all it takes is a little roughness in the distribution of matter.

Edit: And until we know for certain where all that matter came from in the first place, it's kind of hard to say where it's going.

[redsniper]

I still like the crazy daisy-chain of universes inside black holes inside universes kind of thing we got talking about in that one thread, where you just funnel the entropy in a big loop from universe to universe.

[castor]

Heat death isn't the end of the universe?

The whole concept sounds rather poetic to begin with