Alonso, J.L.Boucaud, Ph.Martín Mayor, Víctorvan der Sijs, A.J.2023-06-202023-06-202000-02-010556-282110.1103/PhysRevD.61.034501https://hdl.handle.net/20.500.14352/60326© 1999 The American Physical Society. We are indebted to L.A. Fernández for very helpful remarks and stimulating discussions. We also acknowledge interesting discussions with A. Cruz, Ph. de Forcrand, M.A. Stephanov, and A. Tarancón. We thank the RTNN collaboration for computing facilities. This work is financially supported by CICYT (Spain), projects AEN 96-1670, AEN 96- 1674, AEN 97-1680 and by Acción Integrada HispanoFrancesa HF1996-0022.The phase diagram at zero temperature of a lattice SU(2) scalar-fermion model in 211 dimensions is studied numerically and with mean-field methods. Special attention is devoted to the strong coupling regime. We have developed a new method to adapt the hybrid Monte Carlo algorithm to the O(3) non-linear σ model constraint. The charged excitations in the various phases are studied at the mean-field level. Bound states of two charged fermions are found in a strongly coupled paramagnetic phase. On the other hand, in the strongly coupled antiferromagnetic phase fermionic excitations around momenta (±π/2, ±π/2, ±π/2) emerge.engjournal articlehttp://dx.doi.org/10.1103/physrevd.61.034501https://journals.aps.orgopen access53Monte-CarloNumerical-simulation3 dimensionsGauge fieldsTransitionNeutrinosAbsenceProof.Física-Modelos matemáticos