REVTex 4 are the "American Physical Society" styles for tetex Reproducible: Always Steps to Reproduce:
Created attachment 9564 [details] revtex-4.ebuild
An update: we're waiting for some improvements to portage, then I will add this package into a new category, something like app-latex. Thanks for your patience! (Scientific packages, like this, are a high priority, so this will be gotten to as soon as possible.)
I think that revtex-4 is already included in tetex-2 or am I mistaken?
Yep, that's correct, it's in tetex-2, thanks for reporting, your patience and the solution in this case.
FYI: Texlive is "mainstream" now, revtex4 is in dev-texlive/texlive-publishers