If there's a limit on how cold something can get, is there a limit on how hot a closed system could get? Can matter be excited beyond a plasma?

yes...read up on the Planck Temperature, it is basically as hot as the universe was before/during the Big Bang

i always understood that the temperature as the time since the big bang approached 0 was infinity.

edit: i just researched it, and it seems that temperature any higher than the planck temperature would cause matter to become energy, so the above poster is correct.

If we have an Abosolute Zero
then it would only make sense if there were an Absolute Hot

you cant go slower then not moving.. but you can go faster and faster

Though you can't go faster than the speed of the light...

You can't go faster than light but you can (theoretically) increase kinetic energy without bound by getting the speed closer and closer to the speed of light, so if the average speed of the particles in a plasma was 99.9999% of the speed of the light, it would have a very much higher temperature than if the average speed was say 99.9% of the speed of light. The only problem is when you get to the Planck temperature, which modern physics can't really deal with at this point without a quantum theory of gravity.

Pffft.. Says who?

quantum theory of gravity.

We don't even have a good theory for gravity period.

Pffft.. Says who?

Jesus.

i suppose the speed of light is really the upper limit, however, i've heard anecdotally that if you keep increasing your speed, mass increases as well as you approach the speed of light (not sure if that is factual or not), and so if both speed and mass were increasing, wouldn't kinetic energy increase at a large rate? i suppose what i'm trying to say is, if the anecdote i heard is true, and you gain mass instead of velocity when approaching the speed of light, then the upper bound for kinetic energy is dependent on the upper bound for mass/energy present in the universe? which would make sense why the hottest it could ever be was at the beginning of our universe as we know it, when all mass/energy was present in the same place

well, the atoms might simply disintegrate...

everything separates into electrons, protons and neutrons...
this is my theory, based on how all matter stops moving at absolute zero...

Ha, a super-heated swirlling chemical milkshake of bits of atomic particles that were part of individual elements. Is matter turned into energy when the atomic structures of everything break down?

We don't even have a good theory for gravity period.

Well the general theory has been tremendously accurate in tests and only fails where quantum effects are noticeable. I could understand philosophical differences with it, but as for experimental verification in the large scale without quantum effects, its unmatched.

There are several estimates for the maximum obtainable temperature, of which the Planck temperature is one. (Which is roughly 1.41679 x 10^32 Kelvins).

However, whether or not that is truly the hottest possible temperature remains to be seen.

So in short, there is no commonly agreed-upon answer.

I believe, although I may be wrong, that certain things can infact travel faster than light. Čerenkov radiation is one example. Alain Haché I think also did this when he sent laser pulses through some cable made of coaxial photonic crystal.

If anyone can shed some light on this, I would appreciate it.

Har har har. I crack myself up.

I dont think there is a limit to how hot something can get. You would just have to find the matter that could withstand the heat and not desintigrate into nothing.

you cant go slower then not moving.. but you can go faster and faster

No, you can never be completely still, you can be close but the earth will always rotate, and we are not talking about speed were are discussing temperatrue range

No, you can never be completely still, you can be close but the earth will always rotate, and we are not talking about speed were are discussing temperatrue range

But the hotter something gets, the faster the molecules vibrate.

Eventually, yes. there will be a absolute temperature. The molecules will vibrate so fast that the intermolecular bonds will break, resulting in, well.....we dunno. maybe an explosion of sorts

I'm guessing it would decay into nothingness.

could it be that they form an all new substance?

Once it reachs the optimale heat?

Energy is neither created nor destroyed and for an isolated system the entropy can remain constant or increase. Sooner or later the disorder of the universe will reach a peak and there will be no more useful energy. Of course this means there is a limit to how hot something/universe can be.

I thought that all mater is energy condensed to a lower vibration.
heres tom with the weather

yes there is.

If there is a limit to how hot something could get. It would have to be the point at which fusion or fission occurs (like in a sun or nucleur bomb). At this point matter would become energy and different form/s of matter. So the maximum temperature would be hotter than the sun right

Saying that the hottest temperature is hotter than the sun is like saying the coldest temperatre is colder than your freezer

I'm sure there's a max. temperature because there is (likely) a limit of how fast particles can move. If there is no such limit in speed, there is no limit in temperature.

The read on Planck temperature is very interesting.

The idea that matter simply becomes energy at a certain tempertature is a easy way to think about it. However considering the reverse of the big bang however, my guess would be that our nice little range of known particles interact through the various exchange particles produced by the increasing energy, and interactions with each other until a range of more massive particles is produced from the startin particles.

Up and down quarks would escape from protons and neutrons, (kinetic energy becomes greater than the potential energy of the force holding them in place), etc. Quarks interact at high velocities to form charm/strange quarks, or perhaps top/bottom quarks - an example

Basically the range of light particles becomes a range of more heavy particles (greater mass = greater Kinetic energy so its a fitting idea).

To actually determine a limit of this process - limiting the temperature that a system can reach - you would need to determine what happens when all the mass-energy makes up the most massive particles possible. My guess - it becomes exchange particles and things like x-bosons - but after that its anyones guess!
or so im led to believe

This ^

Light and heat are actually infinitely unlimited. just cos nothing can get colder then absolute zero doesnt mean there isnt a temperature cooler. just like how nothing can get faster then light doent mean there isnt a speed of 3x10^9, its just nothing can reach it. these unit are DESCRIPTION TOOLS that allow us to describe matter. the question should be, could matter have a limit to which its temperature could rise to?

and after reading the question again, i realise this has been a massive waste of time.... Remember kids, read the op, dont assume and be self rightous

well other than the big bang I think the hottest temp. possible would be in the center of the oldest black hole
with every thing compressed into a singularity thats got to be really hot

Yeah, I agree, if something was to just stop moving infinity. Then the surroundings would pull it apart to not matter since it's not strong enough to hold itself together.

Bill Hicks was a legend... but not the hottest thing in the universe.

Cerenkov radiation travels faster than the speed of light in a specific medium like water (~0.7c) but does not travel faster than the speed of light in a vacuum.

As for the m87 superluminial jets, they don't travel faster than the speed of light they just seem to because of relativistic effects.
http://www.physforum.com/index.php?showtopic=5252&st=0

We don't even have a good theory for gravity period.

Read my Regulus Space thread...

Ok lets first note what heat is. Heat is the radiated energy caused by particle expansion and friction.

The limit to how hot something can get deals with pressure movement and friction. The hottest something can get is no where near the max Planck temperature which is theoretical assuming the big bang is correct.

The limit to how hot something can get is referable to energetic aggitation. All materials have different top temperatures. All materials can transit matter states. So we can bypass the lower level energy aggitations and move to Plasma.

Plasma is the state where any matter: particle structure, is heated to high levels of aggitation by the input of energy (most of the time photons). Now so long as the plasma is contained photon energy can be pumped into the plasma increasing its heat. However the more photons are pumped into it the more room the electron field needs and the faster the plasma moves. Containment is thus difficult, assuming we can have a "perfect" containment then the temperature or "hottness" something can get is only limited by the amount of room we are using (ie: compression) and the energy made available.

Since quantum mechanics shows us that the law of conservation of energy doesn't apply at the quantum level, the hottness of something could potentially be unlimited.

But since we do not have the technology for perfect containment the hottest we can get is about 200 times that of our sun at its core before EM containment is lost and the plasma is dispersed (often in an explosion).