[MarianaM (OP)]

John asks...

If it's impossible to reach absolute zero, is there a corresponding degree of heat - an absolute state so hot it cannot be reached?

What do you think?

[chiralSPO]

Yes... though there are different answers depending on how the question is interpretted

Mathematically, that limit is infinity.

Considering general relativity, there are limitations on how fast particles can move (c), which is a big part of the temperature, but because of dilation effects, the energy content (as I understand it) is unlimited--with the unfortunate consequence that a system can theoretically become so hot that the energy content is enough to create a black hole.

Considering thermodynamics, I don't think that anything can get hotter than the big bang (otherwise there would be a flow of heat from colder to warmer). But I don't know how hot that was supposed to have been, and perhaps was "infinite"?

[chiralSPO]

* And this would be a good place to point out that negative temperatures are also possible, though this usually comes up in contrived systems (like lasers).

[geordief]

, I don't think that anything can get hotter than the big bang (otherwise there would be a flow of heat from colder to warmer). But I don't know how hot that was supposed to have been, and perhaps was "infinite"?

Hmm that  strikes me as unlikely (although maybe infinitely difficult to know might apply)


"Infinite" is not a number so are you suggesting that the temperature at BB was unquantifiable?

I can see how this might be if there was only "itself" to compare it to

[syhprum]

Chiralsp

I would agree that the upper limit to temperature must be when the particle has sufficient kinetic energy to collapse into a blackhole and would hazard a guess that would be when the mass equivalent of its kinetic energy reaches the Plank mass 

[chiralSPO]

, I don't think that anything can get hotter than the big bang (otherwise there would be a flow of heat from colder to warmer). But I don't know how hot that was supposed to have been, and perhaps was "infinite"?

Hmm that  strikes me as unlikely (although maybe infinitely difficult to know might apply)


"Infinite" is not a number so are you suggesting that the temperature at BB was unquantifiable?

I can see how this might be if there was only "itself" to compare it to

As I understand it (based on pop-sci descriptions, so...), at the very earliest stages of the big bang, dimensions such as space, time, and mass were not well-defined. I understand this to imply that energy was also undefined initially.

[CPT ArkAngel]

The Planck temperature is probably the maximum possible.

https://en.wikipedia.org/wiki/Planck_temperature

[Bill S]

Mathematically, that limit is infinity.

This must raise the question: What is infinite heat?  It must be the point at which nothing can get any hotter. (?)

So the answer to the question: “… is there a corresponding degree of heat - an absolute state so hot it cannot be reached?” is something like: Yes, when it reaches a point where it can’t get any hotter; which is a point which it can’t reach.   Eh, yes, of course. I think we reached a similar impasse with “infinite speed”, when looking at tachyons.

“The problem is that infinities never exist in the real world. Whenever an infinity pops out of a theory, it is simply a sign that your theory is too simple to handle extreme cases.”  C. Baird.

[chiralSPO]

This must raise the question: What is infinite heat?  It must be the point at which nothing can get any hotter. (?)

So the answer to the question: “… is there a corresponding degree of heat - an absolute state so hot it cannot be reached?” is something like: Yes, when it reaches a point where it can’t get any hotter; which is a point which it can’t reach.   Eh, yes, of course.

Is the concept of an absolute, approachable but unattainable 0 any less ridiculous?

[Bill S]

Is the concept of an absolute, approachable but unattainable 0 any less ridiculous?

That’s more interesting than it looks, at first glance.  HUP tells us why we can’t reach 0K; is there a similar principle/law that tells us why we can’t reach infinity?  What about HUP?  I suspect, not, but I’m no expert.

"Infinite" is not a number…..

I think this might have something to do with it. 

[jeffreyH]

Heat is a transfer of energy. Equilibrium does not transfer energy. Therefore there must be a lower temperature system mixing with a higher temperature system. How does that, a finite system, square with infinity?

[Bored chemist]

"Infinite" is not a number so are you suggesting that the temperature at BB was unquantifiable?

Temperatures are only well defined for equilibrium systems, and the BB isn't one.

[Bill S]

Therefore there must be a lower temperature system mixing with a higher temperature system. How does that, a finite system, square with infinity?

Not surprisingly, I would say, it doesn’t; but I still can’t see any way in which change can occur where there is no time.  So, how does our finite, changing Universe relate to the infinite, “changeless” something?

I think that's the same question that you asked.  Will either of us get an answer?

[Hayseed]

I would say yes, but it has the same character as zero.  It can't be reached.  The most intense(EM) event should be when a heavy proton disintegrates with a heavy anti-proton.  I think there is a limit to the mass of a proton.  Once reached, the energy induce is just re-emitted.  It's a physical dynamic limit.  A frequency limit. Rotational length limit.

It's also the cleanest and 100% efficient, all mass is converted to energy.   One might be able to burn/ignite a star with it.

So whatever that temp is.....just add .0000000000000000000000000000000000000000001 degree.

Gamma heat puts colored heat to shame.  Most wouldn't feel it before they're dead.  What could be hotter than g ray?  It doesn't ionize your molecules, it dissolves them.  Easily dissolve a nucleus. You start to radiate.

Some think a gamma strike jump started life long ago.