Recently, Kim, Shiu and Vafa proposed general consistency conditions for six dimensional supergravity theories with minimal supersymmetry coming from couplings to strings. We test them in explicit perturbative orientifold models in order to unravel the microscopic origin of these constraints. Based on the perturbative data, we conjecture the existence of null charges $Q \cdot Q=0 $ for any six-dimensional theory with at least one tensor multiplet, coupling to string defects of charge $Q$. We then include the new constraint to exclude some six-dimensional supersymmetric anomaly-free examples that have currently no string or F-theory realization. We also investigate the constraints from the couplings to string defects in case where supersymmetry is broken in tachyon free vacua, containing non-BPS configurations of brane supersymmetry breaking type, where the breaking is localized on antibranes. In this case, some conditions have naturally to be changed or relaxed whenever the string defects experience supersymmetry breaking, whereas the constraints are still valid if they are geometrically separated from the supersymmetry breaking source.

中文翻译：

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弦缺陷、超对称性和沼泽地

最近，Kim、Shiu 和 Vafa 提出了六维超引力理论的一般一致性条件，其中从耦合到弦的超对称性最小。我们在显式微扰 orientifold 模型中测试它们，以解开这些约束的微观起源。基于微扰数据，我们推测任何具有至少一个张量多重态的六维理论都存在零电荷 $Q \cdot Q=0 $，与电荷 $Q$ 的弦缺陷耦合。然后，我们包含新约束以排除一些当前没有弦或 F 理论实现的六维超对称无异常示例。我们还研究了从耦合到弦缺陷的约束，以防超对称在无速子真空中被破坏，包含膜超对称破坏类型的非 BPS 配置，其中断裂位于反膜上。在这种情况下，当弦缺陷经历超对称破坏时，一些条件自然会改变或放宽，而如果它们与超对称破坏源在几何上分离，则约束仍然有效。