标题： 超固体暴胀中的引力波增强 显示英文标题

标题： Boosting GWs in Supersolid Inflation

摘要： 由通用自引力介质驱动的膨胀是研究准de-Sitter相期间自发时空对称性破缺影响的一个有趣替代方案，特别是广义相对论的4维微分不变性自发破缺为$ISO(3)$。 有效描述基于四个标量场，这些场描述了超固体的激发。 存在两种类似声子的传播标量自由度，在早期和晚期都以非平凡方式混合，并在超出视界后导致不同标量功率谱之间的非平凡关联。 理论的非线性结构允许在膨胀期间产生次级引力波，其效率足以满足当前实验限制，并具有蓝倾斜的光谱指数。 显示英文摘要

摘要： Inflation driven by a generic self-gravitating medium is an interesting alternative to study the impact of spontaneous spacetime symmetry breaking during a quasi de-Sitter phase, in particular the 4-dimensional diffeomorphism invariance of GR is spontaneously broken down to $ISO(3)$. The effective description is based on four scalar fields that describe the excitations of a supersolid. There are two phonon-like propagating scalar degrees of freedom that mix non-trivially both at early and late times and, after exiting the horizon, give rise to non-trivial correlations among the different scalar power spectra. The non-linear structure of the theory allows a secondary gravitational waves production during inflation, efficient enough to saturate the present experimental bound and with a blue-tilted spectral index.