A Test of Gravity with Pulsar Timing Arrays

Abstract

A successful measurement of the Stochastic Gravitational Wave Background (SGWB) in Pulsar Timing Arrays (PTAs) would open up a new window through which to test the predictions of General Relativity (GR). We consider how these measurements might reveal deviations from GR by studying the overlap reduction function -- the quantity that in GR is approximated by the Hellings-Downs curve -- in some sample modifications of gravity, focusing on the generic prediction of a modified dispersion relation for gravitational waves. We find a distinct signature of such modifications to GR -- a shift in the minimum angle of the angular distribution -- and demonstrate that this shift is quantitatively sensitive to any change in the phase velocity. In a given modification of gravity, this result can be used, in some regions of parameter space, to distinguish the effect of a modified dispersion relation from that due to the presence of extra polarization modes.

v2: add references and discussions. 23 pages, 4 figures

References in corpus (28)

• First M87 Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole
• Gravitational Waves and Gamma-rays from a Binary Neutron Star Merger: GW170817 and GRB 170817A
• Beyond the Cosmological Standard Model
• The NANOGrav 12.5-year Data Set: Search For An Isotropic Stochastic Gravitational-Wave Background
• The International Pulsar Timing Array second data release: Search for an isotropic Gravitational Wave Background
• On the evidence for a common-spectrum process in the search for the nanohertz gravitational-wave background with the Parkes Pulsar Timing Array
• Common-red-signal analysis with 24-yr high-precision timing of the European Pulsar Timing Array: Inferences in the stochastic gravitational-wave background search
• Optimal strategies for gravitational wave stochastic background searches in pulsar timing data
• Graviton Mass Bounds
• Testing General Relativity with the Shadow Size of Sgr A*
• Stochastic backgrounds in alternative theories of gravity: overlap reduction functions for pulsar timing arrays
• Mapping gravitational-wave backgrounds using methods from CMB analysis: Application to pulsar timing arrays
• Vainshtein Mechanism in Binary Pulsars
• Detecting massive gravitons using pulsar timing arrays
• The Speed of Gravity
• Variance of the Hellings-Downs Correlation
• Galileon Radiation from Binary Systems
• Mapping gravitational-wave backgrounds in modified theories of gravity using pulsar timing arrays
• Retarded Green's Function Of A Vainshtein System And Galileon Waves
• Causal Effective Field Theories
• Pulsar and cosmic variances of pulsar timing-array correlation measurements of the stochastic gravitational wave background
• Scalar Gravitational Radiation from Binaries: Vainshtein Mechanism in Time-dependent Systems
• Subluminal stochastic gravitational waves in pulsar-timing arrays and astrometry
• Stochastic gravitational wave background phenomenology in a pulsar timing array
• Detecting the Stochastic Gravitational Wave Background from Massive Gravity with Pulsar Timing Arrays
• Constraining gravitational wave propagation using pulsar timing array correlations
• The Nanohertz Gravitational Wave Astronomer
• Pulsar tests of the graviton mass

Cited by in corpus (15)

• Hunting the stochastic gravitational wave background in pulsar timing array cross correlations through theoretical uncertainty
• Dissecting the Stochastic Gravitational Wave Background with Astrometry
• Testing gravity with cosmic variance-limited pulsar timing array correlations
• Constraints on the velocity of gravitational waves from NANOGrav 15-year data set
• Beyond the Hellings-Downs curve: Non-Einsteinian gravitational waves in pulsar timing array correlations
• Correlations for an anisotropic polarized stochastic gravitational wave background in pulsar timing arrays
• Charting the Nanohertz Gravitational Wave Sky with Pulsar Timing Arrays
• Probing Parity Violation in the Stochastic Gravitational Wave Background with Astrometry
• The impact of large-scale galaxy clustering on the variance of the Hellings-Downs correlation: theoretical framework
• Toward a test of Gaussianity of a gravitational wave background
• Angular correlation and deformed Hellings-Downs curve from spin-2 ultralight dark matter
• A novel probe of graviton dispersion relations at nano-Hertz frequencies
• Effects of Coronal Mass Ejection on PSR J1022+1001 and Possible Mode Change of PSR J2145-0750 in the InPTA DR2
• Connecting Inflation to the NANOGrav 15-year Data Set via Massive Gravity
• Testing No slip model with pulsar timing arrays: NANOGrav and IPTA