Prerequisite

Graduate level knowledge in Standard model of particle physics and basic knowledge in string theory.

Introduction

The Swampland program outlines the necessary conditions for a consistent ultraviolet (UV) completion of quantum gravity. We introduce a recent proposal on the dark dimension, grounded in the Swampland program [1].

First, we review the hierarchy and naturalness problems. Next, we explain the rationale behind the Swampland program [2]. After discussing the relevant principles, we will examine the dark dimension proposal and present the related experimental evidence [3,4,5].

Finally, we will extend the proposal to a warped dark dimension within the Randall-Sundrum model. We show how the Swampland argument leads to the emergence of the electroweak scale once the dark dimension is realized in a warped background. Consequently, a second warped extra dimension at the TeV scale is postulated, addressing the long-standing problem of the hierarchy between the electroweak and Planck scales [6].

During the lecture, we will primarily focus on discussing the physics and brainstorming ideas, rather than delving deeply into the technical aspects of the topic. Feel free to join us and participate in the discussion!

Syllabus

1. Motivation - Review of Naturalness problem - Relevant Swampland principles

2. Dark dimension – Extra dimensions - Applications

3. Warped dark dimension in Randall-Sundrum model

Reference

[1] M. Montero, C. Vafa and I. Valenzuela, The dark dimension and the Swampland, JHEP 02 (2023), 022 [arXiv:2205.12293 [hep-th]].

[2] N. B. Agmon, A. Bedroya, M. J. Kang and C. Vafa, Lectures on the string landscape and the Swampland, [arXiv:2212.06187 [hep-th]].

[3] C. Vafa, Swamplandish Unification of the Dark Sector, [arXiv:2402.00981 [hep-ph]].

[4] L. Anchordoqui, I. Antoniadis and D. Lust, Landscape, Swampland, and Extra Dimensions, [arXiv:2405.04427 [hep-th]].

[5] E. Gonzalo, M. Montero, G. Obied and C. Vafa, Dark dimension gravitons as dark matter, JHEP 11 (2023) 109 [arXiv:2209.09249].

[6] K. Bitaghsir Fadafan and G. Cacciapaglia, The Cosmological Constant, Dark Matter and the ElectroWeak Scale meet in the Swampland, [arXiv:2312.08456 [hep-th]].