Testing String Vacua in the Lab: From a Hidden CMB to Dark Forces in Flux Compactifications

TL;DR

This paper explores how string theory compactifications can produce hidden photons with properties that make them detectable in current or near-future experiments, linking fundamental theory with experimental searches for dark forces.

Contribution

It provides explicit models showing how flux compactifications can generate hidden photons at various energy scales, connecting string theory to phenomenological tests.

Findings

Anisotropic compactifications can produce GeV-scale hidden photons suitable for beam dump experiments.

TeV-scale strings can lead to meV-scale hidden photons, potentially observable via light-shining-through-a-wall experiments.

The models demonstrate the role of moduli stabilization and the Green-Schwarz mechanism in hidden photon phenomenology.

Abstract

We perform a detailed analysis of the phenomenological properties of hidden Abelian gauge bosons with a kinetic mixing with the ordinary photon within type IIB flux compactifications. We study the interplay between moduli stabilisation and the Green-Schwarz mechanism that gives mass to the hidden photon paying particular attention to the role of D-terms. We present two generic classes of explicit Calabi-Yau examples with an isotropic and an anisotropic shape of the extra dimensions showing how the last case turns out to be very promising to make contact with current experiments. In fact, anisotropic compactifications lead naturally to a GeV-scale hidden photon ("dark forces" that can be searched for in beam dump experiments) for an intermediate string scale; or even to an meV-scale hidden photon (which could lead to a "hidden CMB" and can be tested by light-shining-through-a-wall experiments) in the case of TeV-scale strings.