[@DarkwolfX37]

Enthalpy is just total heat in a system, system being defined by whomever is running the test. There's no reason pressure or volume has to decrease as heat is added.
But anti-energy that exists in the same manner as antimatter can't exist in any universe with classical matter because they're two dissimilar things. It'd be like saying that because there are green and red apples, there are green and red oranges because they're both fruits.
I would appreciate it if you expounded on the "infinity problem," but the issue is mathematically bound rather than physically bound. I won't argue that other universes can't have different constants because they're not found in ours, but I will argue that there are very few if any circumstances where different sets of constants fit together mathematically and create a functioning universe. Is life even viable on a theoretical universe with different constants? That decreases the odds even more since the System automatically filters out lifeless universes. It becomes a huge puzzle and there just may not be another set of physical properties that logically and mathematically fit together in a way that doesn't end in a universe ripping apart or fitting together. That notwithstanding, there also has to be some standard of physical laws as they apply to outside of dimensions since that space does exist.
To be fair, Seth's ability has different specifics when compared to Ma'at's. There's a lot of overlap, but also enough difference. I can accept that she can affect these things like that, but I'm also wary that it's as simple as throwing a -1 against the properties.
The issue with noticing opposite spins is that you have to have the matter atom to compare it to. If antihydrogen spins the opposite way when compared to hydrogen, she'd first have to have a case of hydrogen and compare it to the spins of all antihydrogen atoms she encounters. Not to mention that there are other factors that could potentially define antimatter that makes it more difficult to compare. A bulk of it comes from the fact that there are simply so many atoms in matter, but also that on a physical level, antimatter is indistinguishable from regular matter when not directly compared.