Akademik Veri Yönetim Sistemi
Physical Review D, cilt.113, sa.5, ss.1-30, 2026 (SCI-Expanded, Scopus)
We propose a predictive SO(10) grand unified theory (GUT) framework for cosmic inflation within the Palatini R2 formulation of gravity. In this model, a GUT Higgs field simultaneously drives inflation and induces intermediate-scale symmetry breaking, thereby linking primordial cosmology, gauge unification, and formation of topological defects. A subsequent partial inflationary phase of NI ∼ 10–17 e-folds occurring after monopole formation can dilute magnetic monopoles to abundances YM ∼ 10−35–10−27. The model predicts cosmic microwave background (CMB) observables in the range 0.955 ≲ ns ≲ 0.974, accommodating the mild tension between the Planck–BICEP (ns ≃ 0.965) and Planck+ACT (ns ≃ 0.971) measurements via the ϕ < M and ϕ > M branches, respectively, where M denotes the renormalization scale entering the Coleman–Weinberg potential. The predicted tensor-to-scalar ratio, r ≲ 8 × 10−4, is consistent with current observational bounds and may be accessible to forthcoming experiments, including the Simons Observatory and LiteBIRD. Furthermore, correlations among the unification scale MU, the inflationary observables (ns; r), and proton-decay lifetimes reveal a strong complementarity between CMB measurements and proton-decay searches, with regions of parameter space testable by upcoming experiments, such as Hyper-Kamiokande and DUNE.