Pomeranchuk's theorem

{{Short description|Cross section theorem}}

Pomeranchuk's theorem, named after Soviet physicist Isaak Pomeranchuk, states that difference of cross sections of interactions of elementary particles $\backslash kappa\_1+\backslash kappa\_2$ and $\backslash kappa\_1+\backslash bar\{\backslash kappa\_2\}$ (i. e. particle $\{\backslash kappa\_1\}$ with particle $\backslash kappa\_2$, and with its antiparticle $\backslash bar\{\backslash kappa\_2\}$) approach 0 when $s\; \backslash to\; \backslash infty$, where $s$ is the energy in center of mass system.