Space laser interferometers can determine the thermal history of the early Universe

TL;DR

Space-based gravitational wave detectors like DECIGO and BBO can reveal the thermal history of the early Universe, especially the reheat temperature after inflation, which is crucial for understanding cosmology.

Contribution

This paper demonstrates that space laser interferometers can determine the Universe's thermal history and reheat temperature, a novel application of gravitational wave detection.

Findings

Detectors can measure the reheat temperature in the range 10^5-10^9 GeV.

They provide insights into the cosmic thermal history after inflation.

Potential to resolve the gravitino problem in cosmology.

Abstract

It is shown that space-based gravitational wave detectors such as DECIGO and/or Big Bang Observer (BBO) will provide us with invaluable information on the cosmic thermal history after inflation and they will be able to determine the reheat temperature $T_R$ provided that it lies in the range preferred by the cosmological gravitino problem, $T_R\sim 10^{5-9}$ GeV. Therefore it is strongly desired that they will be put into practice as soon as possible.