A path-dependent, dynamical redshift induced by inhomogeneous tidal fields (Weyl curvature) offers a significant alternative to homogeneous expansion, providing a falsifiable signature in cosmological surveys. Unlike standard Friedmann-Lemaître-Robertson-Walker (FLRW) models that assume uniform expansion, this approach considers how light accumulates redshift through inhomogeneously distributed matter structures, particularly at lower redshifts (z \lesssim 0.1).
Key aspects of this path-dependent, Weyl-curved redshift framework include:
- Inhomogeneous Tidal Field Impact: The redshift is determined by local accelerations, geodesic shear, and the tidal forces of the Weyl curvature, creating an integrated “Sachs redshift” that differs along different lines of sight.
- Path-Dependent Deviation: Because the photon’s path encounters varying tidal environments, the luminosity distance-redshift relation exhibits non-isotropic deviations, rather than following a single homogeneous expansion curve.
- Falsifiability & Verification: This framework provides an explicit, testable prediction that can be verified by analyzing directional dependence in low data. Projects like DESI (Dark Energy Spectroscopic Instrument) and Euclid are capable of probing these inhomogeneities in the clustering of galaxies, allowing for a potential distinction between standard models and path-dependent, tidal-induced effects.
- Deviation from Homogeneity: In regions with density gradients (e.g., voids or dense filaments), the relation can diverge significantly from the standard model predictions, aiding in the interpretation of local vs. global expansion.
This approach addresses the “background-level tests” of cosmological data without relying solely on a uniform expansion model, making it a critical test of general relativity in the presence of structure.