AI 中文总结
该研究将2PI形式主义用于宇宙学相变的一致热重求和，得到适用于全温度的有效势，研究模型的相变并分析重求和方案对引力波谱预测的影响。
AI 中文摘要
我们将两粒子不可约（2PI）形式主义作为宇宙学相变研究中一致热重求和的框架。针对一个包含两个混合实标量场的模型，我们在哈特利（Hartree）近似下对2PI有效作用量进行重整化，同时建立其与物理参数的联系，得到了适用于所有温度且避免了传统高温近似方法局限性的哈特利重求和有限温度有效势。利用该势，我们研究了模型中的一步和两步相变，并将结果与文献中广泛使用的重求和方案所得结果进行比较。最后，我们评估了一阶相变产生的引力波谱，证明了重求和方案的选择对预测谱的影响。
英文摘要
We apply the two-particle irreducible (2PI) formalism as a framework for a consistent thermal resummation in studies of cosmological phase transitions. Considering a model with two mixing real scalar fields, we work within the Hartree approximation and renormalize the 2PI effective action, while introducing a connection to physical parameters. This yields the Hartree-resummed finite-temperature effective potential, which is valid for all temperatures and avoids the limitations of conventional methods based on the high-temperature approximation. With this potential, we study one- and two-step transitions within the model, and compare our results with those obtained using resummation schemes widely employed in the literature. Finally, we evaluate the gravitational wave spectrum generated from first-order phase transitions, demonstrating the impact of the choice of resummation scheme on the predicted spectrum.
Comments50 pages, 11 figures, 3 appendices (including the full calculation of the wave-function renormalization factors in the 2PI formalism with real mixing scalars)
