标题： 扭曲的Orientifold平面和无超对称的S对偶性 显示英文标题

标题： Twisted Orientifold planes and S-duality without supersymmetry

摘要： 我们构建了一种新型的IIB弦理论定向对称，它破坏了所有超对称性。 它是一种没有开弦部分的闭弦理论，可以理解为Scherk-Schwarz变形，在无限半径下超对称性得以恢复。 我们猜想它在F理论中通过一个自由作用的轨道空间紧化实现，该轨道空间在椭圆纤维上表现为反射操作。 SL(2,Z)自对偶性在F理论公式中是明显的。 我们显式地构建了该模型中的D膜，并发现稳定的D膜与M理论中的几何预测相匹配。 这种理论的一个显著特点是O平面仅耦合到理论的非零质量扭态。 我们将它们称为扭态O平面。 我们描述了这种扭态O平面的超对称例子，并认为它们在本质上类似于O+和O-平面的组合，其总电荷为零。 显示英文摘要

摘要： We construct a novel orientifold of type IIB string theory that breaks all supersymmetries. It is a closed string theory without open sector and it can be understood as a Scherk-Schwarz deformation in which supersymmetry is restored at infinite radius. We conjecture that it is realised in F-theory as a compactification on a freely acting orbifold that acts as the reflection on the elliptic fibre. The SL(2,Z) selfduality is manifest in the F-theory formulation. We construct explicitly the D-branes in this model and find that stable D-branes match the geometric prediction in M-theory. This theory has the salient feature that the O-planes couple only to the massive twisted states of the theory. We call them twisted O-planes. We describe supersymmetric examples of such twisted O-planes and argue that they are similar in nature to combinations of O+ and O- planes with vanishing total charge.