3-pt Statistics of Cosmological Stochastic Gravitational Waves

Abstract

We consider the 3-pt function (i.e. the bispectrum or non-Gaussianity) for stochastic backgrounds of gravitational waves. We estimate the amplitude of this signal for the primordial inflationary background, gravitational waves generated during preheating, and for gravitational waves produced by self-ordering scalar fields following a global phase transition. To assess detectability, we describe how to extract the 3-pt signal from an idealized interferometric experiment and compute the signal to noise ratio as a function of integration time. The 3-pt signal for the stochastic gravitational wave background generated by inflation is unsurprisingly tiny. For gravitational radiation generated by purely causal, classical mechanisms we find that, no matter how non-linear the process is, the 3-pt correlations produced vanish in direct detection experiments. On the other hand, we show that in scenarios where the B-mode of the CMB is sourced by gravitational waves generated by a global phase transition, a strong 3-pt signal among the polarization modes could also be produced. This may provide another method of distinguishing inflationary B-modes. To carry out this computation, we have developed a diagrammatic approach to the calculation of stochastic gravitational waves sourced by scalar fluids, which has applications beyond the present scenario.

16 pages, 5 figures

References in corpus (21)

• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• Gravitational Wave Spectrum Induced by Primordial Scalar Perturbations
• The stochastic gravitational wave background from turbulence and magnetic fields generated by a first-order phase transition
• Theory and Numerics of Gravitational Waves from Preheating after Inflation
• CMBPol Mission Concept Study: Probing Inflation with CMB Polarization
• A Gravitational Wave Background from Reheating after Hybrid Inflation
• Gravitational Wave Production At The End Of Inflation
• A stochastic background of gravitational waves from hybrid preheating
• Gravitational Waves from Warped Spacetime
• The path to the enhanced and advanced LIGO gravitational-wave detectors
• The "in-in" Formalism and Cosmological Perturbations
• Non-Gaussian Spikes from Chaotic Billiards in Inflation Preheating
• Detection methods for non-Gaussian gravitational wave stochastic backgrounds
• Gravitational waves from self-ordering scalar fields
• Gravitational Waves From the End of Inflation: Computational Strategies
• A Nearly Scale Invariant Spectrum of Gravitational Radiation from Global Phase Transitions
• Stochastic Backgrounds of Gravitational Waves from Cosmological Sources: Techniques and Applications to Preheating
• Thermal Inflation and the Gravitational Wave Background
• Non-Gaussianity analysis of GW background made by short-duration burst signals
• Gaussianity of LISA's confusion backgrounds
• Non-Gaussianity test for discriminating gravitational wave backgrounds around 0.1-1Hz

Cited by in corpus (18)

• Particle production during inflation and gravitational waves detectable by ground-based interferometers
• Probing the gravitational wave background from cosmic strings with LISA
• Primordial Gravitational Waves and Cosmology
• Probing non-Gaussian Stochastic Gravitational Wave Backgrounds with LISA
• Shapes of gravity: Tensor non-Gaussianity and massive spin-2 fields
• Phenomenology of theories of gravity without Lorentz invariance: the preferred frame case
• Multimessenger Cosmology: correlating CMB and SGWB measurements
• Gravity Waves and Primordial Black Holes in Scalar Warm Little Inflation
• Fossilized Gravitational Wave Relic and Primordial Clocks
• Non-Gaussianity in Large Scale Structure and Minkowski Functionals
• Cross-correlations as a Diagnostic Tool for Primordial Gravitational Waves
• Probing a stationary non-Gaussian background of stochastic gravitational waves with pulsar timing arrays
• Probing the Gravitational Wave Signature from Cosmic Phase Transitions at Different Scales
• Gravitational wave non-linearities and pulsar-timing array angular correlations
• Reheating signature in the gravitational wave spectrum from self-ordering scalar fields
• Wigner-Eckart theorem in cosmology: Bispectra for total-angular-momentum waves
• Tensor bispectrum mediated by an excited scalar field during inflation
• Flattened bispectrum of the scalar-induced gravitational waves