AI 中文总结
研究规范对称性破缺产生磁单极子、弦和畴壁等过程中引力波谱，通过规范对称性破缺链$SU(2) \to U(1) \to Z_2 \to 1$及$SU(3) \to SO(3) \to Z_2 \to 1$，结合不同稳定性的复合弦，给出相应引力波谱。
AI 中文摘要
规范对称性破缺$SU(2) \to U(1) \to Z_2 \to 1$相继产生磁单极子、弦以及由弦界定的畴壁（WBS），基本磁单极子携带的$U(1)$磁通量是基本弦的两倍。基本弦及后续的WBS会发射引力波，在其衰变过程中，WBS产生携带与磁单极子相同$U(1)$通量的复合弦网络。依据宇宙演化，给出了由基本弦、WBS以及有效稳定、准稳定或亚稳的复合弦产生的引力波谱。在规范对称性破缺链$SU(3) \to SO(3) \to Z_2 \to 1$中也实现了这三种情况。$SU(2)$和$SU(3)$在文献中都曾作为味规范对称性出现。
英文摘要
The gauge symmetry breaking $SU(2) \to U(1) \to Z_2 \to 1$ successively produces monopoles, strings and domain walls bounded by strings (WBS), with the elementary monopole carrying a $U(1)$ magnetic flux twice as large as the elementary string. The elementary strings and subsequently WBS emit gravitational waves, and during their decay, the WBS yield a network of composite strings that carry the same $U(1)$ flux as the monopoles. Depending on the cosmological evolution, we provide the gravitational wave spectra generated by the elementary strings and WBS, in combination with the composite strings which are either effectively stable, quasistable, or metastable. These three scenarios are also realized in the symmetry breaking chain $SU(3) \to SO(3) \to Z_2 \to 1$. Both $SU(2)$ and $SU(3)$ have appeared in the literature as flavor gauge symmetries.
Comments14 pages, 5 captioned figures
