Gaussian wave packet states of scalar fields in a universe of de Sitter.

In this work, we study quantum effects of a massive scalar field in the de Sitter spacetime. We reduce the problem to that of a time-dependent harmonic oscillator and use exact linear invariants and the dynamic invariant method to derive the corresponding Schrödinger states in terms of solutions of a second order ordinary differential equation. Afterwards, we construct Gaussian wave packet states and calculate the quantum dispersions as well as the quantum correlations for each mode of the quantized scalar field. It is further shown that the center of the Gaussian wave packet remains trapped in the origin. [ABSTRACT FROM AUTHOR]