We study string loop corrections to the gravity kinetic terms in type IIB com- pactifications on Calabi-Yau threefolds or their orbifold limits, in the presence of D 7-branes and orientifold planes. We show that they exhibit in general a logarithmic behaviour in the large volume limit transverse to the D 7-branes, induced by a localised four-dimensional Einstein-Hilbert action that appears at a lower order in the closed string sector, found in the past. Here, we compute the coefficient of the logarithmic corrections and use them to provide an explicit realisation of a mechanism for Kähler moduli stabilisation that we have proposed recently, which does not rely on non-perturbative effects and lead to de Sit- ter vacua. Our result avoids no-go theorems of perturbative stabilisation due to runaway potentials, in a way similar to the Coleman-Weinberg mechanism, and provides a counter example to one of the swampland conjectures concerning de Sitter vacua in quantum grav- ity, once string loop effects are taken into account; it thus paves the way for embedding the Standard Model of particle physics and cosmology in string theory.

中文翻译：

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弦论中的对数环修正、模稳定和德西特真空

我们研究了在存在 D 7-膜和定向折叠平面的情况下，对 Calabi-Yau 三重或其双折极限上的 IIB 型压缩中的重力动力学项的弦环校正。我们表明，它们通常在横向于 D 7 膜的大体积极限中表现出对数行为，这是由过去发现的局部四维爱因斯坦 - 希尔伯特作用引起的，该作用出现在闭合弦扇区中的低阶. 在这里，我们计算对数校正的系数并使用它们来明确实现我们最近提出的 Kähler 模稳定机制，该机制不依赖于非微扰效应并导致德西特真空。我们的结果避免了由于失控电位引起的微扰稳定的不通过定理，以类似于 Coleman-Weinberg 机制的方式，并且一旦考虑到弦环效应，就为有关量子引力中德西特真空的沼泽地猜想之一提供了一个反例；因此，它为将粒子物理学和宇宙学的标准模型嵌入弦论铺平了道路。