Do We Live in the Swampland?

TL;DR

This paper investigates whether the Standard Model and its minimal extensions are consistent with quantum gravity constraints, revealing conflicts with recent swampland conjectures and implications for fundamental physics.

Contribution

It provides a no-go theorem for Higgs sector modifications and shows QCD axion incompatibility with swampland criteria, advancing understanding of quantum gravity constraints on particle physics.

Findings

No-go theorem for Higgs sector modifications

QCD axion incompatible with swampland conjectures

Implications for CP symmetry breaking

Abstract

A low-energy effective theory is said to be in the swampland if it does not have any consistent UV completion inside a theory of quantum gravity. The natural question is if the standard model of particle physics, possibly with some minimal extensions, are in the swampland or not. We discuss this question in view of the recent swampland conjectures. We prove a no-go theorem concerning the modification of the Higgs sector. Moreover, we find that QCD axion is incompatible with the recent swampland conjectures, unless some sophisticated possibilities are considered. We discuss the implications of this result for spontaneous breaking of CP symmetry. We comment on dynamical supersymmetry breaking as well as the issue of multi-valuedness of the potential.