标题： 体重整化和两维缺陷世界中的粒子谱 显示英文标题

标题： Bulk Renormalization and Particle Spectrum in Codimension-Two Brane Worlds

摘要： 我们研究了在codimension-two膜世界中物质场的体环路引起的卡西米尔能量，并讨论了有效场论方法如何允许我们利用此结果对体和膜算符进行重整化。 在计算中，我们明确地对Kaluza-Klein（KK）态进行了求和，采用了一种新的方便的方法，该方法基于zeta函数和维度正则化的综合使用。 在我们考虑的一般模型类别中，包括一个超对称例子，即6D规范手征超引力。 尽管我们的讨论大部分更为一般，但我们详细处理了一类紧化情况，其中额外维参数化了一个橄榄球形状的空间，其大小由体磁通量稳定。 橄榄球几何需要两个膜，它们可以承载标准模型场并同时携带张力和磁通量（体规范场的），这是导数展开中的主要项。 膜的性质会影响KK谱，因此也会影响卡西米尔能量以及膜算符的重整化。 一个非常有趣的特点是，当两个膜携带完全相同的磁通量时，即使膜张力很大，在紧化后仍有一半的体超对称性得以保留。 我们还讨论了这些计算对于宇宙常数自然值的影响，当体有两个大额外维且体超对称性部分保留（或完全破坏）时的情况。 显示英文摘要

摘要： We study the Casimir energy due to bulk loops of matter fields in codimension-two brane worlds and discuss how effective field theory methods allow us to use this result to renormalize the bulk and brane operators. In the calculation we explicitly sum over the Kaluza-Klein (KK) states with a new convenient method, which is based on a combined use of zeta function and dimensional regularization. Among the general class of models we consider we include a supersymmetric example, 6D gauged chiral supergravity. Although much of our discussion is more general, we treat in some detail a class of compactifications, where the extra dimensions parametrize a rugby ball shaped space with size stabilized by a bulk magnetic flux. The rugby ball geometry requires two branes, which can host the Standard Model fields and carry both tension and magnetic flux (of the bulk gauge field), the leading terms in a derivative expansion. The brane properties have an impact on the KK spectrum and therefore on the Casimir energy as well as on the renormalization of the brane operators. A very interesting feature is that when the two branes carry exactly the same amount of flux, one half of the bulk supersymmetries survives after the compactification, even if the brane tensions are large. We also discuss the implications of these calculations for the natural value of the cosmological constant when the bulk has two large extra dimensions and the bulk supersymmetry is partially preserved (or completely broken).