Gravitational wave as probe of superfluid dark matter

TL;DR

This paper explores how gravitational waves can be used to test superfluid dark matter models by analyzing deviations in GW speed caused by the superfluid's properties, with current and future detectors offering promising probes.

Contribution

It introduces a novel method of using gravitational wave observations to constrain superfluid dark matter parameters, linking GW propagation to superfluid properties.

Findings

GW speed deviations depend on SfDM parameters and source properties.

FAST, SKA, and IPTA are promising for probing SfDM.

Future space-based GW detectors can also test SfDM with multimessenger data.

Abstract

In recent years, superfluid dark matter (SfDM) has become a competitive model of emergent modified Newtonian dynamics (MOND) scenario: MOND phenomenons naturally emerge as a derived concept due to an extra force mediated between baryons by phonons as a result of axionlike particles condensed as superfluid at galactic scales; Beyond galactic scales, these axionlike particles behave as normal fluid without phonon-mediated MOND-like force between baryons, therefore SfDM also maintains the usual success of $\Lambda$CDM at cosmological scales. In this paper, we use gravitational waves (GWs) to probe the relevant parameter space of SfDM. GWs through Bose-Einstein condensate (BEC) could propagate with a speed slightly deviation from the speed-of-light due to the change in the effective refractive index, which depends on the SfDM parameters and GW-source properties. We find that Five hundred meter Aperture Spherical Telescope (FAST), Square Kilometre Array (SKA) and International Pulsar Timing Array (IPTA) are the most promising means as GW probe of relevant parameter space of SfDM. Future space-based GW detectors are also capable of probing SfDM if a multimessenger approach is adopted.