2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/187734The recent three-year WMAP data selects large-field models with certain power-law potentials and small-field models for all power-law potentials as consistent inflation models. We study the large-field and small-field inflation model with a quadratic and a quartic potential within the framework of quantum field theory in an expanding Friedmann-Robertson-Walker universe. We find that quantum fluctuations in the small-field model lead to a significant contribution to the effective potential and may have non-negligible effects on the slow-roll parameters predicted by classical theory.RevTex, 10 pages, no figure; Invited talk at CosPA 2006, National Taiwan Univ., Taiwan, Nov. 15-17, 2006AstrophysicsGeneral Relativity and Quantum CosmologyHigh Energy Physics - Theorytext