标题： 引力不稳定性和大标量场跃迁的审查 显示英文标题

标题： Gravitational Instabilities and Censorship of Large Scalar Field Excursions

摘要： 光标量场的大范围局域变化往往会坍缩成黑洞，动态地“审查”远离场空间的点。我们展示了在某些情况下，渐近平坦时空中的大标量跃迁可以通过平滑的卡拉比-丘泡几何来完成紫外化，似乎绕过了四维审查论点。然而，这些时空也表现出与泡状物塌缩或膨胀相关的经典不稳定性，提供了一种不同的审查机制。我们证明了静态KK泡的Kerr族，在维度约化后会产生无限的标量跃迁，是经典的不稳定。我们构建了一组初始数据，其中静态泡位于能量的局部最大值，并给出了一个一般性论证，表明这种性质确实指示了引力中的机械不稳定性。我们还讨论了弦在泡附近的运动行为，这是穿越模空间大跃迁的一个局部探针。 显示英文摘要

摘要： Large, localized variations of light scalar fields tend to collapse into black holes, dynamically "censoring" distant points in field space. We show that in some cases, large scalar excursions in asymptotically flat spacetimes can be UV-completed by smooth Kaluza-Klein bubble geometries, appearing to circumvent 4d censorship arguments. However, these spacetimes also exhibit classical instabilities related to the collapse or expansion of a bubble of nothing, providing a different censorship mechanism. We show that the Kerr family of static KK bubbles, which gives rise to an infinite scalar excursion upon dimensional reduction, is classically unstable. We construct a family of initial data in which the static bubbles sit at a local maximum of the energy, and we give a general argument that such a property indeed indicates mechanical instability in gravity. We also discuss the behavior of wound strings near a bubble, a local probe of the large traversal through moduli space.