Coherent Rotation in Cosmic Filaments

The dynamical state of cosmic filaments remains poorly constrained. While their spatial morphology is well established, coherent filament-aligned rotation over megaparsec scales is not a generic prediction of standard structure-formation models, which typically generate vorticity only in strongly nonlinear regions. This work presents a model-agnostic observational search for coherent rotation in cosmic filaments. Using filament spines identified in large-scale structure catalogs and transverse velocity estimators derived from galaxy peculiar-velocity reconstructions, we construct an axial vorticity proxy for individual filaments. A comprehensive suite of null tests is applied, including axis randomization, local position randomization, and far-environment relocation that preserves geometry while destroying environmental context. Key results: A statistically significant filament-aligned rotation signal is detected. The signal aligns with filament axes and is suppressed under axis randomization. Rotation is partially preserved under local position randomization but strongly suppressed when environmental context is removed. Rotation strength correlates with large-scale environmental asymmetry (Spearman ρ ≈ −0.54, p ≈ 0.014). These results indicate that the detected rotation is both geometry-aligned and environment-dependent, and cannot be readily explained by projection effects or random noise alone. They align with recent independent detections of large-scale filament rotation (Tudorache et al. 2025, MNRAS 544:4306), extending the phenomenon to environmentally modulated kinematics. Interpretation The observed environmental dependence is consistent with a prior prediction of the Spacetime Flow Hypothesis (SFH), which provides one possible causal interpretation in which asymmetric gradients in a scalar resistance field induce azimuthal flow components around filaments. In this framework, filament rotation arises naturally from environmental asymmetry, without invoking primordial vorticity, global rotation, or filament-specific tuning. Foundational Theory Spacetime Flow Hypothesis (v6) — Core Field-Theoretic Framework. DOI : https://doi.org/10.5281/zenodo.17626069 Defines the flow-field, scalar resistance α(x), drift law, energy conservation, and Lagrangian. Empirical Validation Gravitational Waves Orbital Decay — Binary pulsars (GR-level match, first principles). DOI: https://doi.org/10.5281/zenodo.16879389 SN1a — Luminosity distance + time dilation (χ²/dof = 0.934). DOI: https://doi.org/10.5281/zenodo.17624837 Galaxy Rotation Curves — 20/20 fits without dark matter. DOI: https://doi.org/10.5281/zenodo.17014960 Gravitational Lensing Time Delays — 10 strong-lens delays from baryons only. DOI : https://doi.org/10.5281/zenodo.17849232 Predictive Frontier (New V2) Fast-Flow Bubble — Local void explains Hubble tension (11σ match to Pantheon+ residuals). DOI : https://doi.org/10.5281/zenodo.18136251 (New V2) ISW Effect — The Integrated Sachs–Wolfe Effect without Dark Energy: A Causal Gradient Prediction. DOI : https://doi.org/10.5281/zenodo.18136185 Together with prior empirical validations of SFH across binary pulsars, supernova time dilation, galaxy rotation curves, gravitational lensing delays, and large-scale ISW correlations, the present filament-rotation result supports a unified, causal interpretation of gravity based on gradients in the flow of proper time. Filament rotation emerges not as an imposed feature, but as a testable consequence of environmental asymmetry.