Mirror twin Higgs cosmology: constraints and a possible resolution to the H$$_{0}$$ and S$$_{8}$$ tensions

Journal Article · 09 May 2022 · Journal of High Energy Physics (Online)

DOI: https://doi.org/10.1007/jhep05(2022)050 · OSTI ID:1832791

Bansal, Saurabh  ^[1]; Kim, Jeong Han  ^[2]; Kolda, Christopher  ^[3]; Low, Matthew  ^[4]; Tsai, Yuhsin  ^[3]

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1. Univ. of Notre Dame, IN (United States); Univ. of Cincinnati, OH (United States)
2. Chungbuk National University (Korea); Korea Institute for Advanced Study (KIAS), Seoul (Korea, Republic of); Inst. of Basic Science, Daejeon (Korea, Republic of)
3. Univ. of Notre Dame, IN (United States)
4. Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

The mirror twin Higgs model (MTH) is a solution to the Higgs hierarchy problem that provides well-predicted cosmological signatures with only three extra parameters: the temperature of the twin sector, the abundance of twin baryons, and the vacuum expectation value (VEV) of twin electroweak symmetry breaking. These parameters specify the behavior of twin radiation and the acoustic oscillations of twin baryons, which lead to testable effects on the cosmic microwave background (CMB) and large-scale structure (LSS). While collider searches can only probe the twin VEV, through a fit to cosmological data we show that the existing CMB (Planck18 TTTEEE+lowE+lowT+lensing) and LSS (KV450) data already provide useful constraints on the remaining MTH parameters. Additionally, we show that the presence of twin radiation in this model can raise the Hubble constant H$$_{0}$$ while the scattering twin baryons can reduce the matter fluctuations S$$_{8}$$, which helps to relax the observed H$$_{0}$$ and S$$_{8}$$ tensions simultaneously. This scenario is different from the typical ΛCDM + ΔN$$_{eff}$$ model, in which extra radiation helps with the Hubble tension but worsens the S$$_{8}$$ tension. For instance, when including the SH0ES and 2013 Planck SZ data in the fit, we find that a universe with ≳ 20% of the dark matter comprised of twin baryons is preferred over ΛCDM by ~ 4σ. If the twin sector is indeed responsible for resolving the H$$_{0}$$ and S$$_{8}$$ tensions, future measurements from the Euclid satellite and CMB Stage 4 experiment will further measure the twin parameters to O(1 - 10%)-level precision. Our study demonstrates how models with hidden naturalness can potentially be probed using precision cosmological data.

• Research Organization: Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)
• Sponsoring Organization: USDOE Office of Science (SC), High Energy Physics (HEP)
• Grant/Contract Number: AC02-07CH11359
• OSTI ID: 1832791
• Report Number(s): FERMILAB-PUB-21-371-T; arXiv:2110.04317; oai:inspirehep.net:1941247
• Journal Information: Journal of High Energy Physics (Online), Journal Name: Journal of High Energy Physics (Online) Journal Issue: 5 Vol. 2022; ISSN 1029-8479
• Publisher: Springer NatureCopyright Statement
• Country of Publication: United States
• Language: English