Euclid fσ₈ as a Probe of Relaxation-Driven Cyclic Cosmology

Appendix to "Unified CPT-Symmetric Cyclic Cosmology: From Timeless Geometric Foundations to Relaxation-Driven Dynamics with Explicit Bounce Transfer" https://zenodo.org/records/18637610 This note derives the linear growth signatures of Relaxation-Driven Cyclic Cosmology (RDCC) and evaluates the sensitivity of upcoming fσ₈ measurements, particularly from Euclid, to the relaxation parameter α. We show that RDCC remains background-degenerate with ΛCDM while predicting a percent-level suppression in the growth rate through damping of the isocurvature mode. The resulting framework provides a minimal and falsifiable observational window into RDCC dynamics. Michael Lehmannmi.lehmann@gmx.de Related documents and the full RDCC ecosystem are available via Zenodo:https://zenodo.org/records/18204087