Dark matter, dark radiation and gravitational waves from mirror Higgs parity

Abstract

Abstract An exact parity replicates the Standard Model giving a Mirror Standard Model, SM ↔ SM ′ . This “Higgs Parity” and the mirror electroweak symmetry are spontaneously broken by the mirror Higgs, 〈H ′〉 = v ′ ≫ 〈H〉, yielding the Standard Model Higgs as a Pseudo-Nambu-Goldstone Boson of an approximate SU (4) symmetry, with a quartic coupling λ SM(v ′ ) ∼ 10 −3. Mirror electromagnetism is unbroken and dark matter is composed of e ′ and e ¯ ′ $$ {\overline{e}}^{\prime } $$ . Direct detection may be possible via the kinetic mixing portal, and in unified theories this rate is correlated with the proton decay rate. With a high reheat temperature after inflation, the e t dark matter abundance is determined by freeze-out followed by dilution from decays of mirror neutrinos, ν ′ → ℓH . Remarkably, this requires v ′ ∼ (108–1010) GeV, predicting a Higgs mass of 123 ± 3 GeV at 1σ and a Standard Model neutrino mass of (10 −2–10 −1) eV, consistent with observed neutrino masses. The mirror QCD sector exhibits a first order phase transition producing gravitational waves that may be detected by future observations. Mirror glueballs decay to mirror photons giving dark radiation with ∆N eff ∼ 0.03–0.4. With a low reheat temperature after inflation, the e ′ dark matter abundance is determined by freeze-in from the SM sector by either the Higgs or kinetic mixing portal.

Keywords

• Beyond Standard Model
• Cosmology of Theories beyond the SM
• Higgs Physics