Observable Vacuum Stabilizer

This paper addresses the core dilemmas faced by standard Higgs inflation—including the breakdown of the unitarity cutoff, the fundamental conflict between electroweak vacuum metastability and the high-energy inflationary environment, and the fact that existing modification schemes generally sacrifice the framework of general relativity, renormalizability, or the central driving role of the Higgs field—and innovatively proposes a renormalizable vacuum stability element model. Maintaining minimal gravitational coupling throughout, the work introduces only a Standard Model singlet scalar field with a Higgs portal coupling, and rigorously proves—via two-loop renormalization group equations—that electroweak vacuum stability is achieved across the full energy range, with a tunneling lifetime far exceeding the age of the universe. Its most significant highlight is that the RG running and portal coupling compensation naturally induce a critical inflection point in the Higgs field, triggering ultra-slow-roll inflation and reducing the initial condition fine-tuning by a factor of 1000. More importantly, under vacuum stability constraints, the model predicts a definitive positive quantitative correlation between the running of the spectral index and local non-Gaussianity, forming a unique "observational fingerprint" that cannot be mimicked by other models and falls exactly within the detectable window of next-generation CMB experiments. With its minimalist, self-consistent, and UV-complete theoretical framework, this work not only simultaneously resolves multiple fundamental challenges at the intersection of particle physics and cosmology, but also provides a clear and falsifiable cosmological testing pathway for electroweak vacuum stability.