Chiral symmetry restoration in the Nambu-Jona-Lasinio model with a constant electromagnetic field

1989
12 pages
Published in:
  • Phys.Rev.D 39 (1989) 3478-3489

Citations per year

1990199920082017202505101520
Abstract: (APS)
The proper-time Schwinger formalism is implemented in a derivation of the gap equation and total energy of a system of interacting fermions described by the Nambu–Jona-Lasinio model that is minimally coupled to a constant electromagnetic field. Inclusion of a Lagrange multiplier term to vary the scalar density enables the calculation of energy curves as a function of the scalar density that plays the role of an order parameter. A consistent gauge- and Lorentz-invariant regularization of the divergent quantities that occur in this theory is implemented in calculating the total energy and gap relation. Specializing to constant electric fields, we find that a chiral-symmetry-restoration phase transition can occur at a critical value of the electric field. For our choice of parameters, gΛ2/2π2=1.12 and Λ=1041 MeV, one finds the dynamically generated mass mE=0*=208 MeV and critical field eEc=(270 MeV)2. By contrast, a constant magnetic field is found to inhibit the phase transition by stabilizing the chirally broken vacuum state.
  • Jona-Lasinio-Nambu model
  • ELECTROMAGNETIC FIELD
  • SYMMETRY: CHIRAL
  • RENORMALIZATION: REGULARIZATION
  • INVARIANCE: LORENTZ
  • INVARIANCE: GAUGE
  • FIELD THEORY: CRITICAL PHENOMENA
  • FIELD THEORY: VACUUM STATE
  • FIELD THEORY: MASS GENERATION
  • MASS GENERATION: FIELD THEORY