How is negative temperature hotter than infinite temperature?

Question

edit: refer to [this link](https://en.wikipedia.org/wiki/Negative_temperature) for further explanation

In: 0

Answer 1

In Statistical mechanics, temperature is defined by how much entropy you get from adding some energy to the system (Specifically, 1/T=ds/dE). In the most common case of particles in a 3D universe, adding energy always increases entropy, so temperature is always positive.

It is possible to construct a scenario where adding energy to a system causes the entropy to decrease, which would make the temperature negative. In these scenarios, it generally only happens at energy levels above the states with positive temperature

Basically, it requires using a definition of temperature that isn’t particularly relevant in day-to-day life, and a scenario that takes advantage of that particular definition.