A J Parkes - ChronoGravity

Gravitational Waves and Rotating Sources in ChronoGravity: Luminal Propagation, Amplitude Birefringence, and Frame-Dragging Tests ChronoGravity couples a non-propagating cuscuton clock field to a parity-violating gravitational Chern-Simons sector through an explicit four-dimensional slaving postulate. This paper examines the resulting gravitational-wave phenomenology and the consistency of the theory around rotating sources. On the explicitly decoupled cosmological branch, gravitational waves propagate at the metric speed of light. The cuscuton is minimally coupled, the effective galactic scalar sector is absent from the cosmological propagation background, and the Chern-Simons interaction modifies the amplitude evolution of the two circular gravitational-wave polarisations rather than their propagation speed. The resulting observational signature is gravitational-wave amplitude birefringence. Unlike a simple distance-accumulated opacity, the ChronoGravity signal has an endpoint redshift dependence determined by the homogeneous cuscuton tracker. This provides a distinctive frequency- and redshift-dependent template that can in principle be tested using gravitational-wave catalogues. The paper also examines the local rotating-source sector using a gauge-complete calculation rather than assuming that standard dynamical-Chern-Simons Solar-System bounds can be directly imported or automatically evaded. Within the controlled weak-field stellar approximation, the matched nonlinear sequence through ell/L* = 5.1 gives a fractional angular-momentum correction no larger than 1.31 x 10^-15, while rolling-clock feedback is below 10^-39 in the stellar interior. Solar-System frame dragging is therefore not competitive with gravitational-wave polarimetry within the verified numerical regime. A dedicated gravitational-wave catalogue analysis using the ChronoGravity endpoint template, a full relativistic realistic-star calculation, precise convention-normalisation of the birefringence amplitude, and a stochastic-background analysis remain open. #ChronoGravity #Astrophysics #Cosmology #GravitationalWaves #DarkMatter #DarkEnergy @elonmusk @NASA @LIGO @SpaceX @Grok @ProfBrianCox academia.edu/175444976/Gravi… via @academia

ChronoGravity and the Redshift Evolution of the Characteristic Acceleration Scale The ChronoGravity framework predicts that the characteristic MOND acceleration scale is not a universal constant but evolves with cosmic time as  a₀(z) = c H(z) / (2π), where H(z) is the Hubble parameter at redshift z. This prediction follows from the a₀–H₀ consistency relation of the ChronoGravity anchor paper and is fully determined by known ΛCDM parameters — no additional free parameters are introduced. Standard MOND treats a₀ as a fixed universal constant and has no mechanism for any such evolution. We compare the ChronoGravity prediction against two recent observational results: MUSE‑DARK III (Ciocan et al. 2026, A&A accepted), which measured a₀(z ≈ 0.9) = 2.38 ± 0.10 × 10⁻¹⁰ m s⁻²  in 79 star‑forming galaxies at 0.33 < z < 1.44, finding statistically significant redshift evolution; and MIGHTEE‑HI (Varasteanu et al. 2025), which found 2.4σ evidence for increasing a₀ with redshift from resolved H I kinematics. Scaled to the SPARC z = 0 anchor — itself established by a prior validation of ChronoGravity against 175 late‑type galaxies with 0.135 dex RAR scatter — ChronoGravity predicts: a₀(z = 0.9) = 2.01 × 10⁻¹⁰ m s⁻².  The direction of evolution is exactly correct, and the predicted ratio a₀(z)/a₀(0) = 1.68  compares to the observed 1.98 ± 0.44, a 0.7σ discrepancy when SPARC calibration uncertainty is included. We discuss the significance, current limitations, and the specific observational test that would move the result from supportive to strong evidence. #ChronoGravity #TheoreticalPhysics #MUSEDARK3 #MOND #RedshiftEvolution #SPARC #Cosmology @elonmusk @ProfBrianCox @NASA @LIGO @SpaceX @grok academia.edu/172315779/Chron… via @academia

ChronoGravity: Large-Scale Structure, Early Dark Energy, and CMB Consistency -Background and Linear Perturbations We analyse the cosmological predictions of ChronoGravity at the level of the background expansion history, the dark energy equation of state, large-scale structure growth, and-new in this version-linear cosmological perturbations. The scope is fixed by the framework's division of labour: cold dark matter is retained in Ω m , the AQUAL field χ is a galaxy-scale correction decoupled at linear cosmological order, and the cuscuton φ is the only non-standard ingredient in linear cosmology. At the background level, the cuscuton follows a freezing tracker with w φ (z) →-1 from above; for the anchor-paper tracker fraction (∼10% of today's dark energy, ξ = 1.1759) the early dark energy fraction at recombination is Ω EDE (z = 1100) = 2.39 × 10-4 , two orders of magnitude below the Planck+ACT limit, and the sound horizon shifts by only Δr s /r s =-0.0047%. At linear orderderived here by direct machine-verified perturbation of the covariant equationsthe cuscuton perturbation is a pure time translation of the background, δφ = φ̇0δt, carrying no independent degree of freedom and zero anisotropic stress. Its entire effect on the linear Einstein equations collapses to a single multiplicative kernel ε c (k, t) renormalising the momentum constraint, with the closed-form superhorizon ceiling ε c max (z) = (3/2)μ 4 /(M Pl 4 V″), from which φ̇0 cancels. Numerically the ceiling is 6.2% today, declining monotonically into the past; at CMB acoustic-peak scales at recombination the kernel is ε c <~ 3.5 × 10-5 , two orders of magnitude below Planck's fractional precision. The acoustic peak structure therefore survives at first perturbative order, not merely at background level; the only non-negligible correction is an O(few %) modification of the late-time integrated Sachs-Wolfe effect at multipoles buried under cosmic variance. GR recovery on subhorizon scales, previously a structural argument, is here a derived linear-theory result: ε c ∝ a 2 /k 2. A full Boltzmann implementation is thereby reduced from an open question to a confirmation exercise; we give the CLASS blueprint, in which the cuscuton adds no new dynamical variable. #ChronoGravity #TheoreticalPhysics #Cosmology #LargeScaleStructure #EarlyDarkEnergy #CMB @elonmusk @SpaceX @ProfBrianCox @grok @NASA @LIGO academia.edu/172315976/Chron… via @academia

V2.2 - Gravitational Wave Propagation in ChronoGravity: Speed, a Slaved Chern-Simons Sector, and Einstein Telescope Predictions GW170817 established that gravitational waves travel at the speed of light to within |c GW /c-1| < 10-15 , excluding a large class of modified gravity theories including TeVeS and most Horndeski models. We analyse gravitational wave propagation in ChronoGravity, a covariant modified gravity framework with three sectors: a cuscuton scalar field (foliation and dark energy), a spatial AQUAL scalar (MOND galactic phenomenology), and a Chern-Simons (CS) term (parity violation). We show that each sector independently contributes zero correction to the tensor kinetic term, so c GW = c #ChronoGravity #TheoreticalPhysics #GravitationalWaves #SlavedChernSimons #EinsteinTelescope #Cosmology #DarkMatter #DarkEnergy @elonmusk @SpaceX @NASA @LIGO @ProfBrianCox @grok academia.edu/172401599/V2_2_… via @academia

ChronoGravity - Anchor Paper: A Covariant 4D Framework with Cuscuton Foliation, MOND from Spatial AQUAL, and a 5D Origin This paper presents the corrected and unified formulation of the ChronoGravity framework. The cuscuton field is shown to define a global time foliation rather than a static spatial potential: its equation of motion is a prescribed-mean-curvature condition on its level sets. A general no-go lemma follows-no localized static spatial cuscuton profile can exist around a mass-so the cuscuton cannot source MOND-like dynamics. Instead, in every static, high-acceleration regime the cuscuton's timelike gradient pins it to the minimum of its potential, giving exact recovery of General Relativity together with a constant dark-energy term; we clarify here that this is an adiabatic-tracking statement, not a claim of local freezing, since the constant-φ leaves are constant-mean-curvature surfaces that track the global expansion. Galactic phenomenology is carried by a separate spatial scalar sector built on the cuscuton foliation; its |Y| 3/2 action reproduces the AQUAL equation, the deep-MOND scaling g #ChronoGravity #TheoreticalPhysics #Cosmology #DarkEnergy #DarkMatter @elonmusk @ProfBrianCox @grok academia.edu/172412045/Chron… via @academia

Spiral Galaxies in Cluster Cores: A Testable Prediction from a Time-Based Theory of Gravity Galaxies spin too fast. Their outer stars orbit at speeds that the visible matter cannot account for-by a wide margin. The standard explanation is dark matter: unseen mass, five times more abundant than everything visible, that nobody has yet detected directly despite forty years of searching. The alternative explanation is that gravity itself behaves differently at very low accelerations. This paper concerns a theory of the second kind, and reports a prediction sharp enough to settle a piece of the question using telescope data that already exists. #ChronoGravity #SpiralGalaxies #DarkEnergy #DarkMatter #Cosmology #TheoreticalPhysics @grok academia.edu/172412570/Spira… via @academia

V1.1 A No-Go Theorem for Environment-Dependent Gravitational Couplings of Dark Matter V1.1 - I spotted rendering errors in some of the equations in the previous version. this one should now be correct. Fingers Crossed! Hybrid frameworks that reproduce galactic dynamics through modified gravity while retaining cold dark matter cosmologically face a double-counting problem: dark matter clustering around galaxies adds to a modification already calibrated to reproduce the observed rotation curves. A widely considered resolution is to suppress dark matter's gravitational coupling in galactic environments while preserving it on cluster and cosmological scales, using some environmental variable as a selector. We show that this entire class of proposals is forbidden. If the effective gravitational source takes the form T b + f(x)T d with f a position-dependent coupling, the contracted Bianchi identity together with separate conservation of the two matter sectors requires T d μν ∇ μ f = 0, hence ∇f = 0 wherever dark matter is present. The coupling must be constant. The result is independent of the dark sector's equation of state, of the functional form of f, and of which environmental variable f is built from. We discuss the two remaining escape routes-promoting f to a dynamical field, and species-constant couplings-and note that each faces its own well-defined obstruction. #ChronoGravity #TheoreticalPhysics #Cosmology #DarkEnergy #DarkMatter @grok academia.edu/172401750/V1_1_… via @academia

ChronoGravity: What It Is ChronoGravity is a modified‑gravity framework in which the galactic acceleration scale emerges from spacetime structure rather than being inserted by hand. This overview introduces the core principles of the theory, its geometric motivation, and the role of temporal curvature in producing MOND‑like phenomenology without dark matter on galactic scales. We outline how ChronoGravity reconciles galactic dynamics with cosmological structure formation, describe the origin of its characteristic scale, and explain how its predictions differ from both ΛCDM and traditional MOND formulations. The aim of this document is to provide a clear, accessible introduction to the conceptual foundations of ChronoGravity, situating it within the broader landscape of modified‑gravity research and preparing readers for the technical papers that follow. #Chronogravity #TheoreticalPhysics #Gravity academia.edu/172312928/Chron… via @academia

🚀 Launch Post — ChronoGravity v13.7 Today I’m releasing ChronoGravity v13.6, the fully corrected anchor paper of the framework I’ve been building for the past two years. This version finally locks the whole picture into place. What ChronoGravity does: • It shows that the cuscuton isn’t a MOND field at all — it’s the universe’s global clock, giving a clean GR limit everywhere local gravity is strong. • It puts MOND where it belongs: in a separate spatial scalar living on the cuscuton’s slices, reproducing AQUAL, the deep‑MOND scaling, and the Tully–Fisher relation. • It fixes the Chern–Simons sector completely: the pseudoscalar is slaved to the cuscuton, carries no new degrees of freedom, and affects only gravitational‑wave birefringence, not galaxy rotation curves. • It gives a corrected cosmology where the cuscuton’s energy density is purely potential, producing a freezing tracker with a small early‑dark‑energy component. • And it ties all three sectors to a single geometric origin in five dimensions. The result is a clean division of labour: cuscuton = foliation + dark energy χ = MOND CS = gravitational‑wave birefringence only If you want the full story, I’ve put a 1‑page preview below and the full paper is now live on OSF, here's the link: osf.io/9rch2/files/osfstorag… #Physics #Cosmology #Astrophysics #Gravitation #GeneralRelativity #ModifiedGravity #MOND #DarkEnergy #GravitationalWaves @elonmusk @SpaceX @NASA @LIGO

Thanks @Anthrocyberbot for making this video on my latest paper where I test ChronoGravity Theory using real SPARC data from 175 galaxies over 4 decades. Check out the video in the link below: youtu.be/a-v3OLCSTr4 😎🚀👍 #Chronogravity #SPARC #NASA #LIGO #SpaceX