2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/28089We present the doping dependence of the spectral functions, density of states and low frequency behavior of the self-energy for the 2D Hubbard model on the basis of our recently developed theory for the Hubbard model. Strong 2D critical spin fluctuations dominating near half-filling are completely destroyed by 13 and 20 percent doping concentrations for U=4 and 8, respectively. Below these concentrations the imaginary part of the self-energy vanishes quadratically in frequency near the Fermi energy, a characteristic feature for the Fermi liquid.4 pages, revtex, 5 figuresCondensed Mattertext