Cosmological perturbations in \bar{QCD}- inflation. Estimates confronting the observations, including BICEP2

摘要

We discuss a new scenario for early cosmology, when inflationary de Sitterphase dynamically emergent. This genuine quantum effect occurs as a result ofdynamics of the topologically nontrivial sectors in a (conjectured) stronglycoupled QCD- like gauge theory with scale ${\Lambda_{\overline{\mathrm{QCD}}}}\sim 10^{17} $ GeV in expanding universe. Inflaton in this${\overline{\mathrm{QCD}}}$- inflation framework is an auxiliarynon-propagating field, similar to an effective field known to emerge intopologically ordered condensed matter systems. Number of e-folds in the${\overline{\mathrm{QCD}}}$-inflation framework is determined by the gaugecoupling constant at the moment of inflation, and estimated as $N_{\rm inf}\sim\alpha^{-2}(H_0)\sim 10^2$. We analyze the equation of state in this frameworkat the end of inflation in terms of the gauge dynamics and confront ourestimates with observations. We make predictions for the tensor tilt, $n_t\simeq -0.02$, the running of the tensor tilt $\alpha_t= {\partialn_t}/{\partial \ln k}\sim \alpha^4(H_0)\sim 10^{-4}$ and the running for thespectral index $\alpha_s= {\partial n_s}/{\partial \ln k}\sim \alpha^4(H_0)\sim10^{-4}$ in terms of the same gauge coupling constant $\alpha(H_0)$, which isfixed in our framework by recent BICEP2 measurements of the tensor fraction$r\simeq 0.2$.