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  • Open Access

Ultralight Dark Matter Statistics for Pulsar Timing Detection

Kimberly K. Boddy*

Jeff A. Dror† and Austin Lam‡

  • Institute for Fundamental Theory, Physics Department, University of Florida, Gainesville, Florida 32611, USA

  • *Contact author: kboddy@physics.utexas.edu
  • †Contact author: jeffdror@ufl.edu
  • ‡Contact author: a.lam2@ufl.edu
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Phys. Rev. Lett. 135, 101001 – Published 2 September, 2025

DOI: https://doi.org/10.1103/hgnx-w1dn

Abstract

Fluctuations in ultralight dark matter produce significant metric perturbations, which may be detected by monitoring the arrival times of light from millisecond pulsars. While searches using this technique are already underway, they do not consistently account for the statistical properties of the dark matter field. The statistics of this field depend on the velocity dispersion of dark matter and, consequently, its coherence length. In the mass range relevant for pulsar timing arrays, the coherence length is comparable to separations between pulsars, making it crucial to incorporate its effects into the analysis. This Letter presents a consistent statistical method for gravitational direct detection of ultralight dark matter. Our key result is the derivation of the two-point function of the metric fluctuations, which we apply to pulsar timing and discuss its implementation in future searches.

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Phys. Rev. Lett. 135, 101001– Published 2 September, 2025
  • Received 11 April 2025
  • Accepted 25 July 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.

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