Resolution of the BAO Sound-Horizon Discrepancy via an Information-Theoretic Extension of ΛCDM

Bryce Weiner

doi:10.59973/ipil.328

Authors

Bryce Weiner Independent Researcher, Sibalom, Antique, Philippines https://orcid.org/0009-0002-8058-9013

DOI:

https://doi.org/10.59973/ipil.328

Keywords:

Cosmological parameters, Cosmic background radiation, Cosmology theory, Large-scale structure of Universe

Abstract

We construct a quantum information-theoretic extension of flat ΛCDM in which a strict information account within the causal diamond of the observable universe yields a controlled enhancement of the sound horizon that quantitatively matches the baryon acoustic oscillation (BAO) tension at the percent level, without introducing additional free parameters in the BAO fit. The holographic entropy bound and the Margolus–Levitin limit define an intrinsic information-processing rate γ along timelike geodesics, while entropy mechanics enforces a fixed partition of von Neumann entropy between coherent evolution and irre-
versible record formation. Applied to the Thomson-scattering channel at z ≃ 1100, this information ledger shows that the baryon-photon plasma necessarily resides in a quantum Zeno regime in which established coherence outpaces projective collapse, so that decoherent entropy is deferred and a negative effective damping term arises in the long-wavelength acoustic mode. A Lindblad–Zeno scaling analysis compresses this open-system response into a dimensionless amplification functional Fav, yielding a coherent acoustic enhancement coefficient α ≈ −5.7 and an enhanced sound horizon rs = 150.71 Mpc, both fixed by fundamental constants and recombination physics. This extended ΛCDM framework reproduces the leading phenomenological impact of early dark energy at recombination without new fields and is statistically favored, in joint BAO plus supernova fits, over the standard ΛCDM ruler and representative alternative mechanisms.

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