Relaxation-Driven Cyclic Cosmology v1.2 A Minimal Model with Emergent Tilt, Mirror Dark Matter, and Testable ISW Excess ISW Excess

Relaxation-Driven Cyclic Cosmology (RDCC) v1.2 presents a refined and fully self-consistent formulation of a minimal, non-singular cyclic cosmological model based on a single complex scalar field. The scalar field is explicitly treated as an effective order-parameter field within an effective field theory framework, with no assumptions about ultraviolet completion. A symmetric double-well potential protected by a discrete symmetry acquires a small, emergent tilt via Coleman–Weinberg radiative corrections, constituting a technically natural soft symmetry breaking. Field relaxation drives a time-dependent vacuum energy and late-time cosmic acceleration without fine-tuning. A CPT-conjugate mirror vacuum with reversed thermodynamic arrow acts as effective cold dark matter, requiring no additional particle species or modified gravity. The relaxation phase functions as a dynamical attractor for cosmological perturbations, suppressing cycle-to-cycle memory effects. RDCC predicts a characteristic enhancement of the late-time Integrated Sachs–Wolfe (ISW) effect at low multipoles (≈12% relative to ΛCDM), providing a concrete and falsifiable observational signature testable by upcoming Euclid and CMB-S4 data. Version 1.2 incorporates conceptual clarifications regarding effective field theory interpretation, technical naturalness, and perturbation stability, while preserving the strict minimalism and observational focus of earlier versions.