Is there a maximum temperature?

[Narmer]

If the world were continuous there would be no need for a quantum theory of gravity. The planck scale is the point where gravity must be reconciled with the other three forces of nature. Once we get to sub Planck scales everything is governed by the uncertainty principle so dimensions and causality fly out the window. It's rather difficult to quantify the meaningless and it's so troublesome that it's known as "The problem of time". There is reason to suspect that time doesn't exist, but it's an illusion caused by universal expansion. Sub Planck? Even that doesn't exist.

Problem of time? Damn. I didn't know this simple question held the key to so many bigger questions. Are we getting off track here?