The Relative Entropy of One Graviton Creation in Early Universe
Anom Trenggana (a*), Freddy P. Zen (a,b)

a) Theoretical Physics Laboratory, THEPI Division, Institut Teknologi Bandung, Jl. Ganesha 10 Bandung 40132, West Java, Indonesia
*gstanomagung[at]gmail.com
b) Indonesian Center for Theoritecal and Mathematical Physics (ICTMP), Jl. Ganesha 10 Bandung 40132, West Java, Indonesia

Abstract

The detection of nonclassicality of primordial gravitational waves (PGWs) is one way to prove the quantum theory of gravity. The nonclassical feature can be seen as a non-gaussianity, that could happen if there is a graviton creation in a squeezed state of Bunch-Davies vacuum. This condition would also produce an entanglement state. In this paper, that non-gaussianity is studied by using relative entropy as a measurement. For the simplest state (one graviton creation), we find that non-gaussianity would only appear on the small squeezed parameter and the entanglement would only take an effect in this condition. For a large squeezed parameter the relative entropy always comes to zero, even in the presence of matter fields the zero value still exists.

Keywords: Non-gaussianity- Relative entropy- Graviton

Topic: Theoretical High Energy Physics