Memory of a Random Walk: Astrometric deflections from gravitational wave memory accumulation over cosmological scales

Abstract

We study the impact of gravitational wave memory on the distribution of far away light sources in the sky. For the first time we compute the built up of small, but permanent tensor distortions of the metric over cosmological time-scales using realistic models of compact binary coalescences (CBCs) whose rate of occurrence is extrapolated at $z\sim \mathcal{O}(1)$. This allows for a consistent computation of the random-walk like evolution of gravitational wave memory which, in turn, is used to estimate the overall shape and magnitude of astrometric deflections of far away sources of light. We find that for pulsar or quasar proper motions, the near-Earth contribution to the astrometric deflections dominates the result and the deflection is analogous to a stochastic gravitational wave memory background that is generally subdominant to the primary stochastic gravitational wave background. We find that this contribution can be within the reach of future surveys such as Theia. Finally, we also study the deviation of the presently observed angular distribution of quasars from perfect isotropy, which arises from the slow build-up of gravitational wave memory over the entire history of the universe. In this case, we find that astrometric deflections depend on the entire light trajectory from the source to the Earth, yielding a quadruple pattern whose magnitude is unlikely to be within reach of the next generation of astrometric surveys due to shot noise and cosmic variance limitations.

17 Pages, 8 Figures

References in corpus (32)

• GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral
• The Gaia mission
• Advanced Virgo: a 2nd generation interferometric gravitational wave detector
• Advanced LIGO
• The NANOGrav 15-year Data Set: Evidence for a Gravitational-Wave Background
• A gravitational-wave standard siren measurement of the Hubble constant
• Search for an isotropic gravitational-wave background with the Parkes Pulsar Timing Array
• Searching for the nano-Hertz stochastic gravitational wave background with the Chinese Pulsar Timing Array Data Release I
• The second data release from the European Pulsar Timing Array III. Search for gravitational wave signals
• Observation of gravitational waves from two neutron star-black hole coalescences
• The merger rate of primordial-black-hole binaries
• The NANOGrav 15-year Data Set: Constraints on Supermassive Black Hole Binaries from the Gravitational Wave Background
• Gravitational wave generation from bubble collisions in first-order phase transitions: an analytic approach
• Gravitational wave stochastic background from cosmic (super)strings
• Gravitational-Wave Stochastic Background from Kinks and Cusps on Cosmic Strings
• The gravitational-wave memory effect
• Relating gravitational wave constraints from primordial nucleosynthesis, pulsar timing, laser interferometers, and the CMB: implications for the early universe
• Gravitational wave bursts from cosmic (super)strings: Quantitative analysis and constraints
• Cosmic string loop distribution on all length scales and at any redshift
• Stochastic Gravitational-Wave Background due to Primordial Binary Black Hole Mergers
• Measuring a Parity Violation Signature in the Early Universe via Ground-based Laser Interferometers
• Thanks for the memory: measuring gravitational-wave memory in the first LIGO/Virgo gravitational-wave transient catalog
• Gravitational Waves from the First Stars
• The Cosmological Memory Effect
• Examination of a simple example of gravitational wave memory
• Gravitational wave memory in $\Lambda$CDM cosmology
• Inferring fundamental spacetime symmetries with gravitational-wave memory: from LISA to the Einstein Telescope
• Astrometric Effects of Gravitational Wave Backgrounds with non-Luminal Propagation Speeds
• Angular Power Spectra with Finite Counts
• Detection of Gravitational memory effect in LISA using triggers from ground-based detectors
• Persistent Astrometric Deflections from Gravitational-Wave Memory
• Gravitational wave stochastic background from cosmological particle decay

Cited by in corpus (2)

• Modeling the BMS transformation induced by a binary black hole merger
• Microscopic primordial black holes as macroscopic dark matter from large extra dimensions