Modifications by QCD transition and $e^{+}{e}^{-}$ annihilation on analytic spectrum of relic gravitational waves in accelerating universe

Shuang Wang, Yang Zhang, Tian-Yang Xia +1

As predicted by quantum chromodynamics(QCD), around $T\sim 190$ MeV in the early universe, the QCD transition occurs during which the quarks are combined into the massive hadrons.…