Inflaton vacuum fluctuations as dark matter and the potential V(phi) as dark energy

TL;DR

This paper proposes that inflaton vacuum fluctuations produced during inflation can account for dark matter and dark energy, challenging standard assumptions and suggesting a unified quantum process underlying cosmic acceleration and matter content.

Contribution

It introduces a novel quantum field theory approach showing inflaton fluctuations can serve as dark matter and dark energy without reheating, revising traditional inflationary models.

Findings

Inflaton fluctuations can produce sufficient particles to avoid reheating.

Quantum fluctuations can revert to the potential, acting as dark energy.

The model challenges the need for the potential V(phi) to vanish.

Abstract

It is shown, using quantum field theory in curved spacetime, how the expansion of the universe during inflation produces an aggregate of particles and inflaton vacuum fluctuations at a temperature of 5x10^17GeV and dense enough to make reheating unnecessary. The standard calculation that predicts the Hubble parameter has to be way smaller than the Planck energy is shown to be fallacious: it applies the conservation of the perturbative curvature R to a single inflaton fluctuation when it should be applied to the energy density contrast of an aggregate. The quantum inflaton fluctuations varphi are with respect to the classical value phi_0 of the inflaton field phi=phi_0+varphi. Fluctuations varphi that have grown to the size of the horizon, or a pair of virtual particles that are separated by a distance the length of the horizon, are forced to become real and take energy from the potential V(phi_0). The slowing down of inflation is due to the eventual domination of the continuously being created radiation over the decreasing inflaton potential V(phi_0). It is not necessary at all for the potential V(phi_0) to go to zero. Since there is no need for reheating the inflaton field phi does not couple to matter (except gravitationally). After inflation, the fluctuations varphi quickly cool down and can be described as dark matter. Now the inverse process begins to occur. Inflaton fluctuations varphi that exited the horizon during inflation begin reentering it after inflation's end. Then they are again causally connected and have a probability of undergoing the inverse of the quantum process they underwent before and give their energy back to the potential V(phi_0). The varphi fluctuations are turning into V(phi_0), which acts as dark energy and accelerates again the expansion of the universe. The disintegration of a perturbation is a quantum jump of cosmological size.