TITLE:
Galactic Rotation Curves Explained in the 4DEU Framework by 3D Spatial Curvature from Local Gravitational Blocking of Cosmic Expansion: No Need for Dark Matter
AUTHORS:
Domenico Maglione
KEYWORDS:
Dark Matter Problem, Four-Dimensional Electromagnetic Universe (4DEU), Galaxy Rotation Curves Fitting, SPARC Database, Gravitational Constraint, Dark Halo as Spatial Curvature
JOURNAL NAME:
Journal of High Energy Physics, Gravitation and Cosmology,
Vol.12 No.1,
January
23,
2026
ABSTRACT: The observed near flatness of galactic rotation curves has long been interpreted as evidence for large amounts of non-baryonic dark matter. Here we show that this phenomenon can be fully explained within the Four-Dimensional Electromagnetic Universe (4DEU) theory. In this framework, gravitation arises from curvature confined to the three-dimensional (3D) spatial hypersurface of a four-dimensional (4D) universe. The so-called “dark halo” does not correspond to any new form of matter but to the intrinsic 3D spatial curvature produced by the gravitational constraint that locally blocks only the 3D component of the 4D cosmic expansion within gravitationally bound systems. Using a Hamiltonian formulation restricted to static spatial slicing (vanishing extrinsic curvature), the effective density sourcing the curvature naturally separates into a baryonic term and an additional geometric contribution associated with the constraint. To test this hypothesis quantitatively, we analyzed the rotation curves from the entire SPARC database, selecting the 129 galaxies that satisfy the statistical and physical quality criteria defined in the method section. The extra-velocity component
v
extra
=
v
obs
2
−
v
bar
2
was fitted in log-log space with the relation
v
cve
(
r
)=
V
0
(
r/
R
ref
)
ε/2
, where
v
cve
(
r
)
denotes the extra velocity component predicted by the 4DEU model, corresponding to the extra-baryonic curvature term that replaces dark matter in ΛCDM.
V
0
represents the characteristic velocity at the reference radius
R
ref
, and
ε
is the radial-flexibility parameter quantifying incomplete blocking of the 3D-only cosmic expansion in the outermost regions. Model parameters were obtained via weighted least-squares, and their statistical consistency was assessed through
χ
2
, and p-value evaluation in logarithmic space. Out of the 129 SPARC galaxies that met the selection criteria, 128 yielded statistically consistent fits (
p≥0.01
), demonstrating that their outer rotation curves are quantitatively reproduced by the curvature-from-gravitational-constraint mechanism alone, without invoking dark matter, modified gravity, or any additional hypothesis. These results provide strong empirical support for the view that the apparent dark halos are a manifestation of 3D spatial curvature induced by the local suppression of 3D-only cosmic expansion, not by new particles. The 4DEU theoretical framework therefore offers a unified and parameter-free geometric explanation of galactic dynamics consistent with observational data across the SPARC sample.