Theta-terms in nonlinear sigma-models
High Energy Physics - Theory
2009-10-31 v2 Condensed Matter
High Energy Physics - Phenomenology
Abstract
We trace the origin of theta-terms in non-linear sigma-models as a nonperturbative anomaly of current algebras. The non-linear sigma-models emerge as a low energy limit of fermionic sigma-models. The latter describe Dirac fermions coupled to chiral bosonic fields. We discuss the geometric phases in three hierarchies of fermionic sigma-models in spacetime dimension (d+1) with chiral bosonic fields taking values on d-, d+1-, and d+2-dimensional spheres. The geometric phases in the first two hierarchies are theta-terms. We emphasize a relation between theta-terms and quantum numbers of solitons.
Cite
@article{arxiv.hep-th/9911025,
title = {Theta-terms in nonlinear sigma-models},
author = {A. G. Abanov and P. B. Wiegmann},
journal= {arXiv preprint arXiv:hep-th/9911025},
year = {2009}
}
Comments
10 pages, no figures, revtex, typos corrected