Skip to content
DraconiticResearch
Search Sources API
186,123 studies31 sourcesUpdated 45 min ago
Peer-reviewedCC BY 4.0Monthly Notices of the Royal Astronomical Society

Testing Covarying Coupling Constants (CCC) against the full SPARC rotation-curve sample: a like-for-like comparison with MOND and NFW

  • Rajendra P Gupta1
  • Nikolaos Samaras1
  1. 1Department of Physics, University of Ottawa , Ottawa, ON K1N 6N5 ,
Open at sourcePDFDOICite

Abstract

The Covarying Coupling Constants (CCC) framework, developed to account for high-redshift JWST (James Webb Space Telescope) observations, contains a mechanism – a covarying-constant virtual mass field keyed to local density – that modifies galactic dynamics without particle dark matter. We test it against the full Spitzer Photometry and Accurate Rotation Curves sample of 175 disc galaxies, extending an earlier study of a few objects. Working in an inverse formulation, in which each model predicts the baryonic rotation curve from the observed one, we compare CCC against Modified Newtonian Dynamics (MOND) and one- and two-parameter Navarro–Frenk–White (NFW) haloes on identical footing, using the reduced χ 2ν. We show that the published sharp density turn-off is unphysical and replace it with a smooth transition – the density-space analogue of the MOND interpolating function, with no new parameter. One-parameter smooth-CCC then performs comparably to galaxy-by-galaxy fitted MOND (lower χ 2ν in 56 per cent of galaxies, mean χ 2ν of 2.58 versus 2.65; the difference is not significant), while two-parameter NFW shows a substantially broader fit-quality distribution and a larger tail of poor or boundary-limited fits (mean χ 2ν ≈ 7). The CCC turn-off density is not universal (scatter 0.82 dex) and correlates with galaxy size, as expected for a spherical reconstruction of flattened discs. Recast as an acceleration, however, at = Vflat2/Rt has scatter 0.33 dex (91-galaxy resolved subset), matching the MOND scale a0 (0.34 dex), of comparable magnitude (∼2× 10−10 m s−2), with its size correlation removed. Though not designed for galactic dynamics, CCC describes rotation curves as well as galaxy-by-galaxy fitted MOND.

Versions

Related

  1. Vertical gradients of Galactic rotation from Gaia: The limiting-cone and comparison models
    Łukasz Bratek, Joanna Jałocha, Szymon Sikora +1
    Astronomy & AstrophysicsPeer-reviewedPublisher termsSolar & stellar physicsCrossref
  2. Hybrid stars with hyperons: structure based on QCD sum rule coupling constants
    F. Moradi Jangal, H. R. Moshfegh, K. Azizi
    arXivPreprintCC BY 4.0Full textHigh-energy astrophysicsSolar & stellar physicsarXiv
  3. A New Window for Testing the PPN in the Strong-Field Regime: Stellar Rotation of S301
    Mohsen Khodadi, Salvatore Capozziello
    arXivPreprintarXiv licenceFull textHigh-energy astrophysicsGravitation & general relativityarXiv
  4. Rotation Curves and Gravitational Lensing in Four Isolated Galaxies: A Comparison Between MOND and the κ-Model
    Gianni Pascoli
    UniversePeer-reviewedCC BYGalaxiesHAL
  5. Measuring the spatio-temporal variation of fundamental physical constants using the OH sum rules
    Renzhi Su, Minfeng Gu
    arXivPreprintCC BY-NC-ND 4.0Full textCosmologyarXiv

Cite

BibTeXRIS
BibTeX
@article{gupta2026testing,
  title = {{Testing Covarying Coupling Constants (CCC) against the full SPARC rotation-curve sample: a like-for-like comparison with MOND and NFW}},
  author = {Rajendra P Gupta and Nikolaos Samaras},
  journal = {Monthly Notices of the Royal Astronomical Society},
  year = {2026},
  month = oct,
  doi = {10.1093/mnras/stag1777},
  url = {https://academic.oup.com/mnras/article/doi/10.1093/mnras/stag1777/8910539},
  note = {CC BY 4.0},
}
RIS
TY  - JOUR
TI  - Testing Covarying Coupling Constants (CCC) against the full SPARC rotation-curve sample: a like-for-like comparison with MOND and NFW
AU  - Rajendra P Gupta
AU  - Nikolaos Samaras
PY  - 2026
DA  - 2026/10/12
JO  - Monthly Notices of the Royal Astronomical Society
DO  - 10.1093/mnras/stag1777
UR  - https://academic.oup.com/mnras/article/doi/10.1093/mnras/stag1777/8910539
AB  - The Covarying Coupling Constants (CCC) framework, developed to account for high-redshift JWST (James Webb Space Telescope) observations, contains a mechanism – a covarying-constant virtual mass field keyed to local density – that modifies galactic dynamics without particle dark matter. We test it against the full Spitzer Photometry and Accurate Rotation Curves sample of 175 disc galaxies, extending an earlier study of a few objects. Working in an inverse formulation, in which each model predicts the baryonic rotation curve from the observed one, we compare CCC against Modified Newtonian Dynamics (MOND) and one- and two-parameter Navarro–Frenk–White (NFW) haloes on identical footing, using the reduced χ ^2_ν. We show that the published sharp density turn-off is unphysical and replace it with a smooth transition – the density-space analogue of the MOND interpolating function, with no new parameter. One-parameter smooth-CCC then performs comparably to galaxy-by-galaxy fitted MOND (lower χ ^2_ν in 56 per cent of galaxies, mean χ ^2_ν of 2.58 versus 2.65; the difference is not significant), while two-parameter NFW shows a substantially broader fit-quality distribution and a larger tail of poor or boundary-limited fits (mean χ ^2_ν ≈ 7). The CCC turn-off density is not universal (scatter 0.82 dex) and correlates with galaxy size, as expected for a spherical reconstruction of flattened discs. Recast as an acceleration, however, a_t = V_flat^2/R_t has scatter 0.33 dex (91-galaxy resolved subset), matching the MOND scale a_0 (0.34 dex), of comparable magnitude (∼2× 10^−10 m s^−2), with its size correlation removed. Though not designed for galactic dynamics, CCC describes rotation curves as well as galaxy-by-galaxy fitted MOND.
SN  - 0035-8711
SN  - 1365-2966
ER  -