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arXiv · 2412.19514

HBT Interferometry and Quantum Nature of Primordial Gravitational Waves in Ho\v{r}ava-Lifshitz Gravity

Sugumi Kanno·Hiroki Matsui·Shinji Mukohyama
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Abstract

Ho\v{r}ava-Lifshitz gravity (to be precise, its projectable version) is recognized as a renormalizable, unitary, and asymptotically free quantum field theory of gravity. Notably, one of its cosmological predictions is that it can produce scale-invariant primordial density fluctuations and primordial gravitational waves without relying on inflation. In this paper, we investigate the quantum nature of the primordial gravitational waves generated in Ho\v{r}ava-Lifshitz gravity. It has been suggested that, for some inflationary models, the non-classicality of primordial gravitational waves in the squeezed coherent quantum state can be detected using the Hanbury Brown - Twiss (HBT) interferometry. We show that in Ho\v{r}ava-Lifshitz gravity, scale-invariant primordial gravitational waves can be generated during both the radiation-dominated and matter-dominated eras of the Universe. Moreover, the frequency range of their quantum signatures is shown to extend beyond that of inflationary models.

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Sugumi Kanno, Hiroki Matsui, Shinji Mukohyama. 2024-12-27. HBT Interferometry and Quantum Nature of Primordial Gravitational Waves in Ho\v{r}ava-Lifshitz Gravity. https://doi.org/10.1103/physrevd.111.104077

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