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Is There Such a Thing As Absolute Hot?
AlpineR writes "Is there an opposite to absolute zero? An article from PBS's NOVA online explains several theories of the maximum possible temperature. Maybe it's the Planck temperature, 10^32 K, beyond which the known laws of physics break down. Or maybe just 10^30 K, the limit of some versions of string theory. If space is actually 11-dimensional then the maximum temperature could even be as low as 10^17 K, attainable by the Large Hadron Collider. Or maybe infinite temperature wraps around to negative temperature and absolute hot is the same as absolute cold."
That's what you get for writing a universe in C.
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While it may well be that there is a maximum "energy density" for a particular space, it would not really be a true opposite to absolute zero. Absolute zero represents complete cessation of motion... a true opposite would be infinite motion (obviously not infinite velocity). Also, it seems quite possible that whatever upper limit exists at one particular time in one particular space may differ from another... either varying as the universe ages, with whatever gravitational field may exist locally, or at the very least in different universes that may exist. As such, while absolute zero is just that... absolute (in that no heat is no heat under all conceivable reference points), "absolute heat" almost certainly does not uniformly exist. I suppose another way to say is that if you plug absolute zero in as the value in a mathematical calculation, you will always get the same result, but there is no one value "absolute heat" corresponding, which can closely approach actually existing in our universe.
we should switch the scale of hotness: accept Carmen Electra as 1 unit of hotness as measured in the year 2000. Also accept that 2 Carmen Electras is twice as hot as 1 Carmen Electra. As the number of Carmen Electras approaches infinity, their total combined hotness approaches some saturation limit, after which it is no longer possible to determine whether hotness of N x Carmen Electra is greater than hotness of (N+1) x Carmen Electra, which breaks down the laws of mathematics and thus the laws of physics by making N=N+1.
I must add that Chuck Norris can kick Carmen Electra's ass even at the hotness limit.
You can't handle the truth.
Temperature is basically the average kinetic energy of the particles, and kinetic energy is half the mass times velocity squared, when things start to get very hot, the particles would eventually start getting up to relativistic speeds.
This has lead some people to suggest that the cosmic speed limit (the speed of light) imposes a cosmic temperature limit - but that's NOT the case.
As things start to move closer and closer to the speed of light, relativity says that their mass increases (as seen from the perspective of an outside observer). Whilst there is a cosmic speed limit - as you approach it, your mass increases without limit. Since unlimited mass and finite velocity means unlimited kinetic energy, relativity does not impose a cosmic temperature limit.
If there is a cosmic temperature limit, it's caused by something else.
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>All this, of course, is purely theoretical and can never be accomplished because it's hard to accelerate any particle infinitely. But according to relativistic physics, an infinite temperature can exist.
No, relativity requires the application of infinite energy to reach the infinite temperature, just like classic mechanics. For this very reason it's impossible to reach it - you don't have the source of infinite energy in our Universe (probably).
However, quantum mechanics has _another_ theoretical limit. I don't really know its precise reason, but this 'handwaving' argument holds: imagine that you have a particle with VERY large speed. The mass of this particle can be large enough to create a black hole. And it will immediately start to lose mass due to Hawking radiation, which will be directed along the path of the black hole (due to relativistic focusing) in the opposite direction (it'll look like black hole with retrorockets).
So it's not possible to reach the infinite speed because our Universe seems to have the _maximum_ allowed finite speed.
"Is there such a thing as absolute hot?" 1. Turn on a burner on the stove. Turn it up as high as it will go. 2. Wait 5 minutes for the burner to warm up. 3. Place the palm of your hand on the burner...
Very efficient: you test for absolute hot and absolute stupid all at the same time.
Table-ized A.I.
But no one has tied relativity to quantum mechanics yet. Therefore those speed limits only apply to a narrow vision of the universe.
Sorry but Special Relativity and Quantum Mechanics are very well integrated: it was first done by Dirac in ~1932 and led to the prediction of anti-matter which was discovered a few years later with the positron (anti-electron). The Dirac (along with the Klein-Gordon and Proca) equations form the underpinnings of Quantum Field Theory which is what we use in particle physics to describe all the fundamental particles of nature (that we know of) and how they interact (except via gravity). This has Lorentz invariance built into it and is a complete union of QM and SR.
What is harder is to unify QM and GR. This has not been successfully done yet. You can create a quantized gravitational field relatively easily but the problem is that you have to specify a maximum energy scale in order to normalize it (in 3+1D at least). This is bad because there is no justification for a maximum energy scale once you include gravity where the physics will change. Hence either the theory is wrong or there is something else at some really high energy. In either case you cannot use it to make meaningful predictions and so we say we have no valid way, yet, to unify QM nd GR.