有偏域壁网络及其引力波
Biased Domain Wall Networks and their Gravitational Waves
AI总结：
研究宇宙域壁网络湮灭，通过3 + 1格点场论模拟，分析种群偏差引发坍缩情况，得出网络衰变温度及引力波频谱，更新相关结果，增强自发破缺离散对称性可行性，为引力波搜索提供频谱。
AI中文摘要：
宇宙域壁网络是早期宇宙随机引力波背景中最有趣的来源之一。我们对其湮灭进行了全面分析，重点关注由种群偏差引发坍缩的情况，即两个简并真空中的一个最初比另一个更受青睐。我们在膨胀宇宙中进行的最先进的3 + 1格点场论模拟表明，网络在温度\(T_{ann}\sim T_s\,\mathcal{B}_s^{0.8}\)附近衰变，其中\(\mathcal{B}_s\)量化了在温度\(T_s\)的标度 regime开始时对一个真空相对于另一个真空的偏好。此外，我们获得了此类网络的引力波频谱，并与依赖于势中微小显式对称性破缺的替代潜在偏差湮灭机制进行了详细比较。顺便提一下，我们更新了这些网络及其引力波演化的结果，并澄清了近期文献中的现有分歧。我们的结果增强了自发破缺离散对称性的现象学可行性，并提供了脉冲星计时阵列（PTA）和地基干涉仪（LIGO - Virgo - KAGRA）在搜索宇宙学引力波背景时可以轻易使用的引力波频谱。
英文摘要：
Cosmic Domain Wall networks are among the most interesting sources of a stochastic Gravitational Wave (GW) background from the early Universe. We present a thorough analysis of their annihilation, with a focus on scenarios where the collapse is induced by a population bias, whereby one of two degenerate vacua is initially preferred over the other. Our state-of-the-art $3+1$ lattice field theory simulations in the expanding Universe reveal that the network decays around the temperature $T_\text{ann}\sim T_s\,\mathcal{B}_s^{0.8}$, where $\mathcal{B}_s$ quantifies the preference for one vacuum over the other at the onset of the scaling regime at the temperature $T_s$. Furthermore, we obtain the spectrum of GWs from such networks, and provide a detailed comparison with the alternative potential bias annihilation mechanism that relies on a small explicit symmetry breaking in the potential. En passant, we update results on the evolution of these networks and on their GWs, and clarify existing disagreements in the recent literature. Our results sharpen the phenomenological viability of spontaneously broken discrete symmetries, and provide GW spectra that Pulsar Timing Arrays (PTAs) and ground-based interferometers (LIGO-Virgo-KAGRA) can readily use in their searches for a cosmological GW background.
