We investigate first order phase transitions arising from hidden sectors which are in thermal equilibrium with the Standard Model bath in the Early Universe. Focusing on two simplified scenarios, an higgsed U(1) and a two scalar singlet model, we show the impact of friction effects acting on the bubble walls on the gravitational wave spectra and on the consequences for present and future interferometer experiments. We further comment on the possibility of disentangling the properties of the underlying theory featuring the first order phase transition should a stochastic gravitational wave signal be discovered.

中文翻译：

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规范对称性破缺的引力痕迹

我们研究了在早期宇宙中与标准模型浴处于热平衡状态的隐藏扇区产生的一阶相变。关注两个简化的场景，higgsed U(1) 和两个标量单线态模型，我们展示了作用在气泡壁上的摩擦效应对引力波谱的影响以及对当前和未来干涉仪实验的影响。如果发现随机引力波信号，我们进一步评论了解开以一阶相变为特征的基础理论的性质的可能性。