早期宇宙中非线性亚尺度熵涨落的演化

我们考察了在宇宙早期阶段（$T\approx 100$ GeV 到 $T\approx 1$keV）由 neutrino、质子和光子引起的非线性亚尺度熵涨落的阻尼。 presented for broad ranges of initial fluctuation amplitudes and length scales. These calculations include a detailed treatment of neutrino inflation, neutron and proton diffusion, photon diffusive heat transport, and hydrodynamic expansion with photon-electron Thomson drag. Neutrino inflation is treated both in the diffusive heat transport regime where neutrinos are optically thick on the length scales of the fluctuations, and in the homogeneous heating regime where neutrinos are optically thin on these scales. We find considerable convergence in amplitude evolution for appreciable ranges in initial fluctuation length scales and amplitudes. Fluctuations produced with the right characteristics at very early times ($T$ $^>_{\sim}$ 100 GeV) are found to survive through the nucleosynthesis epoch.