Testing the mean field theory of scalar field dark matter

TL;DR

This paper investigates quantum corrections to classical simulations of scalar field dark matter, showing that quantum effects can significantly alter predictions on astrophysical scales within about 30 dynamical times.

Contribution

It extends existing classical simulations of scalar field dark matter by incorporating quantum corrections and analyzes their impact on astrophysical predictions.

Findings

Quantum corrections reduce density fluctuations.

Quantum pressure effects are enhanced by quantum corrections.

Corrections grow exponentially during collapse, becoming significant in ~30 dynamical times.

Abstract

Scalar field dark matter offers an interesting alternative to the traditional WIMP dark matter picture. Astrophysical and cosmological simulations are useful to constraining the mass of the dark matter particle in this model. This is particularly true at low mass where the wavelike nature of the dark matter particle manifests on astrophysical scales. These simulations typical use a classical field approximation. In this work, we look at extending these simulations to include quantum corrections. We look into both the ways in which large corrections impact the predictions of scalar field dark matter, and the timescales on which these corrections grow large. Corrections tend to lessen density fluctuations and increase the effect of "quantum pressure". During collapse, these corrections grow exponentially, quantum corrections would become important in about ~30 dynamical times. This implies that the predictions of classical field simulations may differ from those with quantum corrections for systems with short dynamical times.