Quantum nature of Wigner function for inflationary tensor perturbations [CL]

http://arxiv.org/abs/2002.01064


We study the Winger function for the inflationary tensor perturbation defined in the real phase space. We compute explicitly the Wigner function including the contributions from the cubic self-interaction Hamintonian of tensor perturbations. Then we argue that it is no longer an appropriate description for the probability distribution in the sense that quantum nature allows negativity around vanishing phase variables. This comes from the non-Gaussian wavefunction in the mixed state as a result of the non-linear interaction between super- and sub-horizon modes. We also show that this is related to the explicit infrared divergence in the Wigner function, in contrast to the trace of the density matrix.

Read this paper on arXiv…

J. Gong and M. Seo
Wed, 5 Feb 20
18/67

Comments: 24 pages