Gravitational wave induced baryon acoustic oscillations

Abstract

We study the impact of gravitational waves originating from a first order phase transition on structure formation. To do so, we perform a second order perturbation analysis in the $1+3$ covariant framework and derive a wave equation in which second order, adiabatic density perturbations of the photon-baryon fluid are sourced by the gravitational wave energy density during radiation domination and on sub-horizon scales. The scale on which such waves affect the energy density perturbation spectrum is found to be proportional to the horizon size at the time of the phase transition times its inverse duration. Consequently, structure of the size of galaxies and bigger can only be affected in this way by relatively late phase transitions at $\ge 10^6\text{s}$. Using cosmic variance as a bound we derive limits on the strength $\alpha$ and the relative duration $(\beta /H_{\ast }{)}^{-1}$ of phase transitions as functions of the time of their occurrence which results in a new exclusion region for the energy density in gravitational waves today. We find that the cosmic variance bound forbids only relative long lasting phase transitions, e.g. $\beta /H_{\ast }\lesssim 6.8$ for $t_{\ast }\approx 5\times 10^{11}\text{s}$, which exhibit a substantial amount of supercooling $\alpha >20$ to affect the matter power spectrum.

38 pages plus Appendix, 13+2 figures

References in corpus (10)

• Gravitational Wave Production by Collisions: More Bubbles
• Singlet Higgs Phenomenology and the Electroweak Phase Transition
• Gravitational wave generation from bubble collisions in first-order phase transitions: an analytic approach
• Relativistic cosmology and large-scale structure
• A new cosmic microwave background constraint to primordial gravitational waves
• A unified explanation for dark matter and electroweak baryogenesis with direct detection and gravitational wave signatures
• Analytic model for the matter power spectrum, its covariance matrix, and baryonic effects
• Baryogenesis and gravity waves from a UV-completed electroweak phase transition
• Improved constraint on the primordial gravitational-wave density using recent cosmological data and its impact on cosmic string models
• Second-order Gauge-invariant Cosmological Perturbation Theory: Current Status updated in 2019

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