Entanglement of arbitrary spin modes in an expanding universe

Pair particle creation is a well-known effect on the domain of field theory in curved space-time. It is shown that the entanglement generations for spin-0 and spin-1/2 modes are different in Friedmann-Robertson-Walker (FRW) space-time. We consider the spin-1 particles in FRW space-time using Duffin-Kemmer-Petiao (DKP) equation and obtain a measure of the generated entanglement. Also, we consider the spin-3/2 particles. We argue that the absolute value of the spin does not play any role in entanglement generation and the differences are due to the bosonic or fermionic properties.