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arXiv · gr-qc/0303084

Relic gravitational waves from colliding bubbles and cosmic turbulence

Alberto Nicolis
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Abstract

A stochastic background of gravitational waves can be generated during a cosmological first order phase transition, at least by two distinct mechanisms: collisions of true vacuum bubbles and turbulence in the cosmic fluid. I compare these two contributions, analyzing their relative importance for a generic phase transition. In particular, a first order electroweak phase transition is expected to generate a gravitational wave signal peaked at a frequency which today falls just within the band of the planned space interferometer LISA. For this transition, I find constraints for the relevant parameters in order to produce a signal within the reach of the sensitivity of LISA. The result is that the transition must be strongly first order, alpha > 0.2. In this regime the signal coming from turbulence dominates over that from colliding bubbles.

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Alberto Nicolis. 2003-03-21. Relic gravitational waves from colliding bubbles and cosmic turbulence. https://doi.org/10.1088/0264-9381%2F21%2F4%2Fl05

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