Primordial gravitational waves in supersolid inflation
Primordial gravitational waves in supersolid inflation
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DOI：
10.1103/physrevd.96.023508
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发表时间：
2016-11
影响因子：
5
通讯作者：
A. Ricciardone;G. Tasinato
中科院分区：
文献类型：
--
作者：
A. Ricciardone;G. Tasinato
Supersolid inflation is a class of inflationary theories that simultaneously breaks time and space reparameterization invariance during inflation, with distinctive features for the dynamics of cosmological fluctuations. We investigate concrete realisations of such a scenario, including non-minimal couplings between gravity and the scalars driving inflation. We focus in particular on the dynamics of primordial gravitational waves and discuss how their properties depend on the pattern of symmetry breaking that we consider. Tensor modes can have a blue spectrum, and for the first time we build models in which the squeezed limit of primordial tensor bispectra can be parametrically enhanced with respect to standard single-field scenarios. At leading order in a perturbative expansion, the tensor-to-scalar ratio depends only on the parameter controlling the breaking of space-reparameterization. It is independent from the quantities controlling the breaking of time-reparameterization, and this represents a difference with standard inflationary models. We discuss cosmological and observational consequences of our findings, and speculate on implications for the detection of such primordial gravitational waves.
