AI 中文总结
该研究针对场论热一阶相变的成核问题，给出含动力学预因子的热衰变率通用公式，通过数值模拟揭示非微扰贡献，提出的方法可大幅减少计算时间，适用于强指数抑制系统。
AI 中文摘要
我们研究场论中热一阶相变过程中成核的动力学效应。聚焦于亚稳态衰变的经典区域，我们给出包含动力学预因子的热衰变率通用公式，并提供其系统评估方法。我们阐述了使实际热衰变率低于平衡理论统计衰变率的物理机制，还讨论了确保稳态热衰变率存在的热条件，在此条件下，我们的公式在指数小修正范围内是精确的。我们证明该公式可重现随机力学和场论中成核率的已知结果，并能将这些结果统一且加以拓展。我们通过简单场论模型的实时数值模拟对此进行说明，观察到显著的非微扰贡献，在衰变率呈中等指数抑制的弱耦合场论中，这些贡献可主导动力学预因子，我们还探讨了这些非微扰效应与振荡子（oscillons）的关联。值得注意的是，我们的数值方法所需计算时间比衰变的直接模拟少指数倍，因此适用于具有任意强指数抑制的系统。最后，我们讨论了热条件被违反、稳态衰变率不存在的小热化或低热化系统。
英文摘要
We study dynamical effects during nucleation in thermal first-order phase transitions in field theory. Focusing on the classical regime of the decay of a metastable state, we present the general formula for the thermal decay rate including the dynamical prefactor and give a recipe for its systematic evaluation. We describe the physical mechanism which reduces the actual thermal decay rate with respect to the statistical rate obtained in equilibrium theory. We also discuss the thermality conditions ensuring the existence of a steady-state thermal rate, in which case our formula is exact up to exponentially small corrections. We show that it reproduces the known results for the nucleation rate in stochastic mechanics and field theory, and allows us to unify and go beyond them. We illustrate this in real-time numerical simulations of simple field theory models. We observe significant non-perturbative contributions which can dominate the dynamical prefactor in weakly-coupled field theories at moderate exponential suppression of the decay rate. We explore the connection of these non-perturbative effects to oscillons. Notably, our numerical method requires exponentially less computing time than direct simulations of decays and is thus applicable to systems with arbitrarily strong exponential suppression. Finally, we discuss small or poorly thermalized systems when the thermality conditions are violated and the steady-state rate does not exist.
Comments68 pages, 15 figures
