Primordial Perturbations, Chladni Resonances and Non-Gaussianity within the HRDCC Framework

The origin of primordial cosmological perturbations remains one of the central questions in modern cosmology. In the standard picture, these perturbations are commonly attributed to quantum fluctuations amplified during an inflationary epoch. Within the HRDCC framework, the same observational problem is approached from a different phenomenological perspective. The present work investigates whether primordial perturbations may phenomenologically emerge from the effective geometric state established during a regularized cosmological transition. Rather than introducing additional microscopic fields, the framework considers the possibility that resonance patterns associated with the evolving effective geometry contribute to the modulation of an effective primordial perturbation spectrum. In this context, effective Chladni resonances are introduced as phenomenological standing geometric patterns that may imprint phase correlations on large-scale perturbations. Within the effective cosmological framework established in earlier papers of the HRDCC publication program, the present work introduces an effective description of resonance-induced perturbation generation and discusses how such resonances may contribute to effective primordial non-Gaussianity. The proposed relations remain phenomenological throughout this work. A microscopic resonance theory is intentionally left for future studies. The resulting phenomenological framework is compatible with a range of observational signatures commonly discussed in modern cosmology, including large-scale CMB phase correlations and departures from purely Gaussian primordial statistics. Quantitative confrontation with cosmological observations is intentionally deferred to subsequent investigations. This manuscript constitutes the first paper of the HRDCC publication program. It is distributed as a preprint and has not undergone formal peer review.