Environmental Asymmetry and Axial 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. NEW : Related Empirical Work. The empirical circulation measurements analyzed here are presented independently in; Filament-Scale Eulerian Circulation in the Cosmic Velocity Field (Beaupré 2026), DOI: https://doi.org/10.5281/zenodo.18371283 which reports the observational detection and null-test validation without model interpretation. The present work builds upon those empirical results by exploring a possible causal interpretation. The empirical findings remain valid regardless of the interpretation adopted. 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 — Core Field-Theoretic Framework. DOI : https://doi.org/10.5281/zenodo.18140096 Defines the flow-field, scalar resistance α(x), drift law, energy conservation, and Lagrangian. Empirical Validation Gravitational Wave Orbital Decay — Binary pulsars (leading-order agreement with GR from first principles). DOI: https://doi.org/10.5281/zenodo.18214948 SN1a — Luminosity distance + time dilation (χ²/dof = 0.934). DOI: https://doi.org/10.5281/zenodo.18217479 Galaxy Rotation Curves — 20/20 fits without dark matter. DOI: https://doi.org/10.5281/zenodo.18136466 Gravitational Lensing Time Delays — 10 strong-lens delays from baryons only. DOI : https://doi.org/10.5281/zenodo.18136510 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. Version 2 (January 2026). Clarifies the interpretation of the rotation–asymmetry relationship (Stage-1 data show an anti-correlation, with coherent rotation suppressed at high asymmetry), aligns Sections 5–6 accordingly, and strengthens contextual comparison with LCDM. No changes to data, estimators, or statistical results.