# Maximum Temperature

#### BTruesdell07

If temperature is the speed that electrons are moving around the nucleus of an atom, and nothing but the speed of light can go the speed of light then shouldn't there be a maximum temperature that is possible. Remember absolute zero is the point where the electrons stop moving. So "absolute 100" could be the point that electrons are moving the speed of light. "Absolute 100" would be the same as absolute 0 and only be theoretically possible

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#### Gokul43201

Staff Emeritus
Gold Member
BTruesdell07 said:
If temperature is the speed that electrons are moving around the nucleus of an atom,
Not true. It is more like the RMS speed of individual atoms.
and nothing but the speed of light can go the speed of light then shouldn't there be a maximum temperature that is possible.
Crudely speaking this is true (though not for the reasons stated). But it is also possible to associate a temperature to a photon distribution, and this makes things a little more tricky.

Remember absolute zero is the point where the electrons stop moving. So "absolute 100" could be the point that electrons are moving the speed of light. "Absolute 100" would be the same as absolute 0 and only be theoretically possible
Unforunately, at anywhere near such temperatures, you do not have bound electrons anymore, so this limit will never be seen in the manner you suggest. Nevertheless, there is an upper limit on the photon density that can be achieved in space (without making a black-hole).

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#### mathman

Very high temperature stuff is usually in plasma form (electrons and nuclei freely moving independently). If you add more energy, it goes into mass increase, since the particles are traveling near the speed of light.

#### CarlB

Homework Helper
BTruesdell07 said:
If temperature is the speed that electrons are moving around the nucleus of an atom, and nothing but the speed of light can go the speed of light then shouldn't there be a maximum temperature that is possible.
Actually, temperature has to do with the energy per degree of freedom, not the speed. And according to relativity, while there is a limit on the speed, there is no limit on the energy.

From a more practical point of view, our physics breaks down at the "Plank Energy", so we have no idea what the equivalent temperatures would be like. Well, they'd be very HOT.

Carl

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