Massless flows, 2. The Exact S matrix approach

Apr, 1993
31 pages
Published in:
  • Int.J.Mod.Phys.A 8 (1993) 5751-5778
e-Print:
Report number:
  • BUHEP-93-9,
  • USC-93-004,
  • LPM-93-08

Citations per year

1993200120092017202502468
Abstract:
We study the spectrum, the massless S-matrices and the ground-state energy of the flows between successive minimal models of conformal field theory, and within the sine-Gordon model with imaginary coefficient of the cosine term (related to the minimal models by ``truncation''). For the minimal models, we find exact S-matrices which describe the scattering of massless kinks, and show using the thermodynamic Bethe ansatz that the resulting non-perturbative c-function (defined by the Casimir energy on a cylinder) flows appropriately between the two theories, as conjectured earlier. For the non-unitary sine-Gordon model, we find unusual behavior. For the range of couplings we can study analytically, the natural S-matrix deduced from the minimal one by ``undoing'' the quantum-group truncation does not reproduce the proper c-function with the TBA. It does, however, describe the correct properties of the model in a magnetic field.
Note:
  • 34 pages, BUHEP-93-6, USC-93-004, LPM-93-08
  • field theory: conformal
  • dimension: 2
  • S-matrix: factorization
  • Yang-Baxter equation
  • energy: ground state
  • particle: spectrum
  • spectrum: particle
  • renormalization group: c-function