Can the gravitational wave background feel wiggles in spacetime?

Abstract

Recently the international pulsar timing array collaboration has announced the first strong evidence for an isotropic gravitational wave background (GWB). We propose that rapid small oscillations (wiggles) in the Hubble parameter would trigger a resonance with the propagating gravitational waves, leaving novel signature in the GWB spectrum in the form of sharp resonance peaks. The proposed signal can appear at all frequency ranges and is common to continuous spectrum GWBs with arbitrary origin. Due to its resonant nature, the signal strength differs by a perturbation order depending on whether the GWB is primordial or not, which makes it a smoking gun for the primordial origin of the observed GWB. We show that a large part of the parameter space of such signal can be constrained by near future PTA observations, while fitting the signal template to the current NanoGrav 15yr data already hints an interesting feature near 15 nHz.

7 pages plus appendix, 5 figures; References added; matched published version in ApJL

References in corpus (33)

• Advanced Virgo: a 2nd generation interferometric gravitational wave detector
• Advanced LIGO
• The NANOGrav 15-year Data Set: Evidence for a Gravitational-Wave Background
• 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
• BICEP / Keck XIII: Improved Constraints on Primordial Gravitational Waves using Planck, WMAP, and BICEP/Keck Observations through the 2018 Observing Season
• The NANOGrav 15-year Data Set: Search for Signals from New Physics
• Gravitational Wave Production by Collisions: More Bubbles
• Early dark energy, the Hubble-parameter tension, and the string axiverse
• The NANOGrav 15-year Data Set: Constraints on Supermassive Black Hole Binaries from the Gravitational Wave Background
• The NANOGrav 15-year Data Set: Observations and Timing of 68 Millisecond Pulsars
• On the evidence for a common-spectrum process in the search for the nanohertz gravitational-wave background with the Parkes Pulsar Timing Array
• Gravitational wave generation from bubble collisions in first-order phase transitions: an analytic approach
• Common-red-signal analysis with 24-yr high-precision timing of the European Pulsar Timing Array: Inferences in the stochastic gravitational-wave background search
• The recent gravitational wave observation by pulsar timing arrays and primordial black holes: the importance of non-gaussianities
• Inflationary interpretation of the stochastic gravitational wave background signal detected by pulsar timing array experiments
• Ultra-Light Scalar Fields and the Growth of Structure in the Universe
• Probing the equation of state of the early Universe with pulsar timing arrays
• Limits on scalar-induced gravitational waves from the stochastic background by pulsar timing array observations
• Beyond Concordance Cosmology with Magnification of Gravitational-Wave Standard Sirens
• The Need For Speed: Rapid Refitting Techniques for Bayesian Spectral Characterization of the Gravitational Wave Background Using PTAs
• The nanohertz stochastic gravitational wave background from cosmic string loops and the abundant high redshift massive galaxies
• Have pulsar timing array methods detected a cosmological phase transition?
• Superheavy quasi-stable strings and walls bounded by strings in the light of NANOGrav 15 year data
• Scalar induced gravitational waves in light of Pulsar Timing Array data
• QCD-Collapsed Domain Walls: QCD Phase Transition and Gravitational Wave Spectroscopy
• Translating nano-Hertz gravitational wave background into primordial perturbations taking account of the cosmological QCD phase transition
• Implications of Nano-Hertz Gravitational Waves on Electroweak Phase Transition in the Singlet Dark Matter Model
• Wiggly tails: a gravitational wave signature of massive fields around black holes
• NANOGrav signal from axion inflation
• Fingerprint of GeV scale right-handed neutrinos on inflationary gravitational waves and PTA data
• Observational constraint on axion dark matter in a realistic halo profile with gravitational waves

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• Parametric resonance of gravitational waves in general scalar-tensor theories
• Stochastic gravitational wave background: birth from string-wall death
• A novel probe of graviton dispersion relations at nano-Hertz frequencies
• Interpreting Pulsar Timing Array data of Gravitational Waves with Ekpyrosis-Bouncing Cosmology
• Climbing over the potential barrier during inflation via null energy condition violation
• Purely quadratic non-Gaussianity from tachyonic instability: Primordial black holes and scalar-induced gravitational waves