Enqvist Kari, Jokinen Asko, Mazumdar Anupam, Multamäki Tuomas, Väihkönen Antti
Helsinki Institute of Physics, University of Helsinki, P.O. Box 64, FIN-00014 Helsinki, Finland.
Phys Rev Lett. 2005 Apr 29;94(16):161301. doi: 10.1103/PhysRevLett.94.161301.
We consider a two-field model for inflation where the second order metric perturbations can be amplified by a parametric resonance during preheating. We demonstrate that there can arise a considerable enhancement of non-Gaussianity sourced by the local terms generated through the coupled perturbations. We argue that the non-Gaussianity parameter could be as large as f(NL) approximately 50. Our results may provide a useful test of preheating in future cosmic microwave background experiments.
我们考虑一种暴胀的双场模型，其中二阶度规微扰在预热期间可通过参量共振被放大。我们证明，由耦合微扰产生的局域项所引发的非高斯性会有显著增强。我们认为非高斯性参数可能大到$f_{NL}\approx50$。我们的结果可能会为未来宇宙微波背景实验中的预热提供一个有用的检验。
