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Symmetry of Cosmological Observables, and a High Hubble Constant as an Indicator of a Mirror World Dark Sector

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arxiv 2107.13000 v2 pith:Y52RHBZV submitted 2021-07-27 astro-ph.CO hep-ph

Symmetry of Cosmological Observables, and a High Hubble Constant as an Indicator of a Mirror World Dark Sector

classification astro-ph.CO hep-ph
keywords cosmologicalscalingconstantdarkfindfree-fallgravitationalhigh
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved
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abstract

We find that a uniform scaling of the gravitational free-fall rates and photon-electron scattering rate leaves most dimensionless cosmological observables nearly invariant. This result opens up a new approach to reconciling cosmic microwave background and large-scale structure observations with high values of the Hubble constant $H_0$: Find a cosmological model in which the scaling transformation can be realized without violating any measurements of quantities not protected by the symmetry. A "mirror world" dark sector allows for effective scaling of the gravitational free-fall rates while respecting the measured mean photon density today. Further model building might bring consistency with the two constraints not yet satisfied: the inferred primordial abundances of deuterium and helium.

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Cited by 6 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. Hubble tension: the shape wall

    astro-ph.CO 2026-07 accept novelty 6.0

    Late-time modifications to the expansion history can raise H0 by at most about 2% (conservative) to 3.7% (permissive) if the CMB acoustic scale is fixed.

  2. The $H_0$ world cup. II. A comprehensive competition between proposed Hubble tension solutions

    astro-ph.CO 2026-07 conditional novelty 6.0

    Against a common 2025-26 dataset (Planck PR4, ACT DR6, SPT-3G, DESI DR2, Pantheon+), early dark energy and early modified gravity models win the H0 competition (~3σ residual tension), while radiation and late-time sol...

  3. Geometric Constraints on the Pre-Recombination Expansion History from the Hubble Tension

    astro-ph.CO 2026-04 unverdicted novelty 6.0

    Model-independent reconstruction shows that early-universe modifications resolving the Hubble tension exist at the background level, requiring a smooth ~15% pre-recombination expansion rate enhancement.

  4. Double the axions, half the tension: multi-field early dark energy eases the Hubble tension

    astro-ph.CO 2026-04 unverdicted novelty 6.0

    Two-field axion-like early dark energy reduces Hubble tension to 1.5 sigma residual and improves high-ell CMB fits over single-field models.

  5. BAO miscalibration cannot rescue late-time solutions to the Hubble tension

    astro-ph.CO 2025-10 accept novelty 6.0

    Even after rescaling BAO data to prefer H0≈73 km/s/Mpc, none of six tested late-time dark-energy models can resolve the Hubble tension once unanchored SNeIa and CMB geometry are included.

  6. Running into tension: primordial black holes from ultra-slow-roll inflation, spectral running, and the Hubble tension

    astro-ph.CO 2026-06 unverdicted novelty 5.0

    EDE models increase inferred α_s from CMB data, strengthening tension with USR PBH models that predict negative running.