Frack, sorry. I messed up big time, didn't I?
Anyway, as it is, thermal energy would increase as the mass it was contained in decreased, correct? Thus, the Big Bang contained the absolute energy of the universe, right? But the key is that that energy couldn't have come into existence on its own. The problem is where all this matter and energy originated.
Also, we don't know a damn thing about dark matter. It's just a theory, and antimatter, well, we all know the destruction that can cause.
The point being, based on the theory of relativity, isn't it entirely possible that you could transform a negative energy value into a negative mass value? Therefore, it is also possible that mass can exist as a negative. The logical conclusion as to the identity of this (keeping in mind that this is all just postulation) anti-matter would be the single most mysterious form of matter in the known universe. Hence, dark or anti matter.
Does that clear things up a bit? I don't know WHAT I was thinking with the Absolute Zero thing. Sorry...
Logic is the ultimate argument; for none can refute logic with anything but logic. Thus, you will always walk away satisfied if you stay logical, knowing either you're right, or you're wrong.