Speaker
Xiang-Xi Zeng
(TDLI)
Description
Scalar-induced gravitational waves (SIGW) are one of the most promising GW sources of the early universe. The particle interactions, on the one hand, could change the equation of state $\omega$ and the sound speed $c_s$ of the cosmic fluid, such as during the QCD crossover; on the other hand, they can also contribute an anisotropic stress to the energy-momentum tensor. Recently, we have proposed a lattice simulation method to compute the SIGW, and I will show that this method can reproduce the known results, including the particle interactions. Since this method can easily be extended to cases with non-Gaussianity, it will help us to give a more precise GW signal and better constraints on PBH abundance.
Author
Xiang-Xi Zeng
(TDLI)