标题： 没有来自平凡轴子的 sphaleron 加热产生的温暖膨胀 显示英文标题

标题： No Warm Inflation From Sphaleron Heating With a Vanilla Axion

摘要： 在有限温度下，轴子与非阿贝尔规范场的耦合会导致由于瞬子加热而产生的耗散。 这一机制非常适合实现温热膨胀，因为它可以在保持势平坦性的同时导致较大的热摩擦。 然而，我们表明，要求轴子$-$具有特定的离散平移对称性和由瞬子效应非微扰生成的势$-$排除了强温缓变膨胀阶段，在此阶段热摩擦占主导地位。 得出这一结果不需要任何现象学输入。 虽然非最小（类轴子）模型提供了一种解决方法，但具有标准轴子的瞬子加热能够使温热膨胀的弱阶段得以实现。 显示英文摘要

摘要： At finite temperature, the coupling of an axion to non-Abelian gauge fields causes dissipation due to sphaleron heating. This mechanism is ideally suited for realizing warm inflation since it can lead to large thermal friction while preserving the flatness of the potential. We show, however, that requiring standard properties of an axion $-$ in particular a discrete shift symmetry and a potential generated non-perturbatively by instanton effects $-$ excludes the strong regime of warm slow-roll inflation, in which thermal friction dominates. The derivation of this result does not require any phenomenological input. While non-minimal (axion-like) models provide a way out, sphaleron heating with a standard axion is capable of enabling the weak regime of warm inflation.