Quantum–Kinetic Dark Energy (QKDE): A GR-preserving dark energy framework with a time-dependent scalar kinetic normalization
Year: 2025
Type: article
Abstract: A minimal, effective dark-energy framework—Quantum–Kinetic Dark Energy (QKDE)—is developed in which the scalar kinetic normalization carries a slow background time dependence, K(t) > 0, while the Einstein–Hilbert metric sector remains unmodified. The effective action is S = ∫ d⁴x √(−g) [ (1/2) Mₚₗ² R + K(t) X − V(φ) ], where X = −(1/2) g^{μν} ∂_μφ ∂_νφ. Within the effective field theory of dark energy (EFT–DE) description, this corresponds to a single nonvanishing function α_K = K φ̇² / (H² Mₚₗ²) > 0, with α_B = α_M = α_T = α_H = 0, so tensor modes are luminal and the Planck mass is constant. Within this effective framework, a closed first-order background system in e-fold time is obtained. Scalar perturbations propagate with sound speed c_s² = 1, satisfy Φ = Ψ, and source linear growth through the unmodified Einstein equation. All observable signatures therefore enter solely through the expansion history H(a) and the induced growth factor D(a). Two kinetic normalizations are treated in detail: (i) a curvature-motivated form K = 1 + α R / M², for which an iteration-free algebraic identity for K′/K is derived; and (ii) a phenomenological running K = 1 + K₀ (1 + z)^p. A reproducible numerical pipeline is provided together with a Fisher forecasting setup based on exact variational (sensitivity) equations for distances, H(z), and fσ₈(z). Stability and admissibility reduce to K(t) > 0 and a nonvanishing algebraic denominator in the curvature case. The framework yields sharp, falsifiable null predictions on linear scales: μ(a,k) = Σ(a,k) = 1, gravitational slip = 0, and c_T² = 1; any statistically significant deviation lies outside the effective QKDE baseline. The framework is interpreted as an effective, unitary-gauge cosmological description defined in a preferred time slicing, rather than as a manifestly covariant scalar–tensor theory.
Author: Brown, Daniel
Institution: University of Utah
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7102667366
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