Transplanckian Censorship and the Local Swampland Distance Conjecture

Abstract

The swampland distance conjecture (SDC) addresses the ability of effective field theory to describe distant points in moduli space. It is natural to ask whether there is a local version of the SDC: is it possible to construct local excitations in an EFT that sample extreme regions of moduli space? In many cases such excitations exhibit horizons or instabilities, suggesting that there are bounds on the size and structure of field excitations that can be achieved in EFT. Static bubbles in ordinary Kaluza-Klein theory provide a simple class of examples: the KK radius goes to zero on a smooth surface, locally probing an infinite distance point, and the bubbles are classically unstable against radial perturbations. However, it is also possible to stabilize KK bubbles at the classical level by adding flux. We study the impact of imposing the Weak Gravity Conjecture (WGC) on these solutions, finding that a rapid pair production instability arises in the presence of charged matter with $q/m\gtrsim 1$. We also analyze 4d electrically charged dilatonic black holes. Small curvature at the horizon imposes a bound $\log (M_{BH})\gtrsim |\Delta \varphi |$, independent of the WGC, and the bound can be strengthened if the particle satisfying the WGC is sufficiently light. We conjecture that quantum gravity in asymptotically flat space requires a general bound on large localized moduli space excursions of the form $|\Delta \varphi |\lesssim |\log (R\Lambda )|$, where $R$ is the size of the minimal region enclosing the excitation and ${\Lambda }^{-1}$ is the short-distance cutoff on local EFT. The bound is qualitatively saturated by the dilatonic black holes and Kaluza-Klein monopoles.

14 pages

References in corpus (6)

• On the Geometry of the String Landscape and the Swampland
• The Swampland: Introduction and Review
• Super-Planckian Spatial Field Variations and Quantum Gravity
• Euclidean Wormholes in String Theory
• Gravitational Instabilities and Censorship of Large Scalar Field Excursions
• The decay of hot KK space

Cited by in corpus (14)

• Lectures on the Swampland Program in String Compactifications
• Merging the Weak Gravity and Distance Conjectures Using BPS Extremal Black Holes
• Swampland Conjectures for Strings and Membranes
• The Convex Hull Swampland Distance Conjecture and Bounds on Non-geodesics
• Finiteness and the Swampland
• Nothing really matters
• 4d strings at strong coupling
• Is Trans-Planckian Censorship a Swampland Conjecture?
• de Sitter Decays to Infinity
• Black Holes as Probes of Moduli Space Geometry
• Constraining the quintessential $\alpha$-attractor inflation through dynamical horizon exit method
• Exploration of a Singular Fluid Spacetime
• Cosmic Censorship of Trans-Planckian Field Ranges in Gravitational Collapse
• Connection Dynamics of Reduced 5-dimensional Kaluza-Klein Theory and Its Deparametrization