Dark Matter, Parallel Universe and Multiple Higgs Signals at the ILC

TL;DR

This paper explores a model where dark matter exists in a parallel universe with its own gauge symmetry, leading to Higgs mixing signatures at the ILC that are unresolvable at the LHC.

Contribution

It introduces a novel parallel universe model with Higgs mixing that predicts unique collider signatures not detectable at the LHC.

Findings

Higgs mixing can produce observable signals at the ILC.

Small mass splitting (~100 MeV) between Higgs bosons makes them indistinguishable at the LHC.

The model provides a new framework for dark matter detection via Higgs signatures.

Abstract

The existence of dark matter is now well established by several indirect experiments. Several candidates for dark matter has also been proposed. However, the dark matter can just be like our ordinary matter in a parallel Universe with both Universes being described by their own non-abelian gauge symmetries forbidding any kinetic mixing. However, the quartic Higgs interactions involving Higgs fields between the two Universes are allowed by the symmetries of the model. The ensuing mixing between the two lightest Standard Model like Higgses gives rise to interesting signatures at the proposed international electron-positron collider (ILC) specially in the case when mass splitting between the two surviving light Higgs bosons are small ($\sim$ 100 MeV) so that they can not be resolved at the LHC.