[mjfl]

Negative temperature actually has some nuance to it. By the relation 1/T = dS/dq where T is temperature, S is entropy and q is heat added to the system, a negative temperature means that entropy decreases when you add heat to the system and increases when it emits heat. By the second law, entropy always goes up, so a negative temperature object will always emit heat. In that way, something with a negative temperature is extremely hot.

[AnimalMuppet]

In fact, it's a negative absolute temperature because it's hotter than infinity.