Testing gravity with cosmic variance-limited pulsar timing array correlations

Abstract

The nanohertz stochastic gravitational wave background (SGWB) is an excellent early universe laboratory for testing the fundamental properties of gravity. In this letter, we elucidate on the full potential of pulsar timing array (PTA) by utilizing cosmic variance-limited, or rather experimental noise-free, correlation measurements to understand the SGWB and by extension gravity. We show that measurements of the angular power spectrum play a pivotal role in the PTA precision era for scientific inferencing. In particular, we illustrate that cosmic variance-limited measurements of the first few power spectrum multipoles enable us to clearly set apart general relativity from alternative theories of gravity. This ultimately conveys that PTAs can be most ambitious for testing gravity in the nanohertz GW regime by zeroing in on the power spectrum.

5 1/2 pages + refs + supp, 4 figures, v4: to appear in PRD Letters, our codes https://github.com/reggiebernardo/PTAfast/tree/main/app3_cvlimitedgravity

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Cited by in corpus (12)

• Dissecting the Stochastic Gravitational Wave Background with Astrometry
• Beyond the Hellings-Downs curve: Non-Einsteinian gravitational waves in pulsar timing array correlations
• Pulsar Timing Array Harmonic Analysis and Source Angular Correlations
• Correlations for an anisotropic polarized stochastic gravitational wave background in pulsar timing arrays
• Charting the Nanohertz Gravitational Wave Sky with Pulsar Timing Arrays
• Toward a test of Gaussianity of a gravitational wave background
• Forecast Analysis of Astrophysical Stochastic Gravitational Wave Background beyond general relativity: A Case Study on Brans-Dicke Gravity
• Connecting Inflation to the NANOGrav 15-year Data Set via Massive Gravity
• Manifestation of Quantum Forces in Spacetime: Towards a General Theory of Quantum Forces
• Identifying the Quadrupolar Nature of Gravitational Wave Background through Space-based Missions
• Testing No slip model with pulsar timing arrays: NANOGrav and IPTA
• Spatial Correlation between Pulsars from Interfering Gravitational-Wave Sources in Massive Gravity