标题： 背景流 anomalies 和对称性 fractionalization 的强制无能隙性 anomalies 显示英文标题

标题： Anomaly Enforced Gaplessness for Background Flux Anomalies and Symmetry Fractionalization

摘要： 反常对称性已被证明能够强烈约束任何重整化群（RG）流的可能红外行为。最近，量子场论（QFT）中对称性概念的扩展提供了新的反常类型，从而对RG流引入了相应的新一类约束。本文中，我们推导出由反常施加在RG流上的约束，这些反常只能在特定背景流的存在下被激活，尽管它们不一定对应于对称性。我们证明，这类反常只能通过具有自发对称破缺或对称分数化的能隙理论来匹配。此外，我们展示了之前未研究过的这些流背景反常的例子，它们出现在$4d$QCD 和$4d$超对称QCD中。 显示英文摘要

摘要： Anomalous symmetries are known to strongly constrain the possible IR behavior along any renormalization group (RG) flow. Recently, the extension of the notion of symmetry in QFT has provided new types of anomalies with a corresponding new class of constraints on RG flows. In this paper, we derive the constraints imposed on RG flows from anomalies that can only be activated in the presence of specific background fluxes even though they do not necessarily correspond to a symmetry. We show that such anomalies can only be matched by gapped theories that exhibit either spontaneous symmetry breaking or symmetry fractionalization. In addition, we exhibit previously unstudied examples of these flux background anomalies that arise in $4d$ QCD and $4d$ SUSY QCD.