Are there upper and lower limits to temperature?

Question

Is absolute zero the lowest possible we can measure or really the coldest temperature?
Is there a corresponding highest temperature?

Answer 1

Yes.

Answer 2

Absolute zero is the lowest possible temperature that can exist. In fact, it is not actually achievable because of the vacuum energy of free space.

Maximum temperatures are harder, because there is no in principle limit. However, what is meant by temperature has to change somewhat when you get to very high values.

In fact, if you want to look at a very wide range of temperature it is often easier to consider the energy per particle, and this is measured typically in electron volts (other units are inconvenient in size).

At room temperature this is around 0.1 eV per particle. At the start of the universe it was around 10^28 eV. Thats a huge range.

Answer 3

Absolute zero describes a theoretical system that neither emits nor absorbs energy. The Absolute zero temperature is known to be 0 K (–273.15 °C). While it is possible to cool any substance to near absolute zero, it may never actually be achieved.

Absolute zero is the point at which particles have a minimum energy, determined by quantum mechanical effects, which is called the zero-point energy.

Answer 4

Zero Kelvin is where all molecular motion ceases. You can't get colder than that for a system in thermal equilibrium. Spin states out of equilibrium with their environment can have negative temperature, though, but that's somewhat of an abstraction. The Planck temperature is the theoretical maximum. Wiki that.

Answer 5

I never deal in absolutes, it is the coldest we know of today. Tomorrow we may have a new way of thinking that re-rights everything we thought was real. For a while nothing was faster than light, until we found a particle that goes faster. So it is cold today and might be Luke warm tomorrow.