Conventional thermodynamics, which is formulated for our world populated by
radiation and matter, can be extended to describe physical properties of
antimatter in two mutually exclusive ways: CP-invariant or CPT-invariant. Here
we refer to invariance of physical laws under charge (C), parity (P) and time
reversal (T) transformations. While in quantum field theory CPT invariance is a
theorem confirmed by experiments, the symmetry principles applied to
macroscopic phenomena or to the whole of the Universe represent only
hypotheses. Since both versions of thermodynamics are different only in their
treatment of antimatter, but are the same in describing our world dominated by
matter, making a clear experimentally justified choice between CP invariance
and CPT invariance in context of thermodynamics is not possible at present.
This work investigates the comparative properties of the CP- and CPT-invariant
extensions of thermodynamics (focusing on the latter, which is less
conventional than the former) and examines conditions under which these
extensions can be experimentally tested.Comment: 20 pages, 4 figures. arXiv admin note: text overlap with
arXiv:1209.198