Sahoo preprint maps a fast-scrambling clock onto dark energy, with proxy Γ ≃ −2.8 ± 0.9

Aliv Sahoo has posted a theoretical preprint, Fast Scrambling Cosmology, asking whether the fast-scrambling time of cosmological horizons imprints on cosmic expansion. Arguments such as trans-Planckian censorship say de Sitter space lasts only an inverse Hubble time times the log of the Planck mass over H. Sahoo adds one term to the Raychaudhuri equation, which governs how the expansion rate changes: minus gamma times H squared, divided by the log of Planck mass squared over H squared, with gamma of order one. Eternal de Sitter space becomes a slowly evolving vacuum, solved with the Lambert W function.

The added term behaves as dark energy with two components. One is a vacuum mode with equation of state w = −1 + 2σ/3. Sigma, gamma over that large log, is nearly constant and far below one today. The other integrates the past of ordinary matter and radiation, so a change in any fluid's equation of state leaves a permanent residual. Neutrinos turning non-relativistic would shift dark-energy density by order sigma times neutrino-mass to the fourth. Nucleosynthesis gives Γ = −3.7 ± 6.1 (68% confidence); published fits give Γ ≃ −2.8 ± 0.9, σ ≃ −0.01 today.

What a general reader should care about is dark energy, the driver of accelerated expansion. Most models add a new field. This preprint imports a clock from quantum information: horizons scramble information in roughly an inverse-Hubble time times a large logarithm, and that clock can nudge the expansion rate. The distinctive claim is a ledger. Dark-energy density would remember when fluids changed equation of state, so a neutrino-mass scale enters the formula. The quoted gamma values rephrase existing expansion fits. They are not a new measurement, and galaxy clustering is untested.

Sahoo flags the needed next step: a dedicated likelihood analysis of structure formation. A covariant clock field reproduces this background, and rescaling the gravitational constant that governs expansion is proposed to remove a short-wavelength instability in the dark-energy era. That fix has not been tested on galaxy clustering. Negative gamma qualitatively follows the DESI DR2 w0wa evolution at redshift above about 1, a hint rather than a joint fit. Methods note: closed-form theory, no new sample, proxy bounds only; unchecked perturbations are the limitation that decides the claim.