Continuum Limit and Improved Action in Lattice Theories. 2. O(N) Nonlinear Sigma Model in Perturbation Theory

The method of paper (I) of this series is applied to the O(N) non-linear sigma model. Due to the use of non-manifestly invariant perturbation theory the improvement part of the action, computed explicitly to one-loop order, is not manifestly O(N) invariant. It can be brought into manifestly O(N) invariant form by use of linear identities among dimension-four operators, which follow from the field equations of the unimproved action. The adequacy of the resulting two-parameter family of manifestly O(N) invariant improved actions is verified to one-loop order.

[1]  B. Dewitt QUANTUM THEORY OF GRAVITY. II. THE MANIFESTLY COVARIANT THEORY. , 1967 .

[2]  W. Zimmermann Normal products and the short distance expansion in the perturbation theory of renormalizable interactions , 1973 .

[3]  W. Zimmermann Composite operators in the perturbation theory of renormalizable interactions , 1973 .

[4]  D. Amit,et al.  Cross-over behavior of the nonlinear σ-model with quadratically broken symmetry , 1978 .

[5]  P. Hasenfratz,et al.  The connection between the Λ parameters of lattice and continuum QCD , 1980 .

[6]  I. Montvay,et al.  Improved continuum limit in the lattice O(3) non-linear sigma model , 1983 .

[7]  K. Symanzik,et al.  Continuum Limit and Improved Action in Lattice Theories. 1. Principles and phi**4 Theory , 1983 .

[8]  N. Mermin,et al.  Absence of Ferromagnetism or Antiferromagnetism in One- or Two-Dimensional Isotropic Heisenberg Models , 1966 .

[9]  F. David QUANTIZATION WITH A GLOBAL CONSTRAINT AND IR FINITENESS OF TWO-DIMENSIONAL GOLDSTONE SYSTEMS , 1981 .

[10]  F. David Cancellations of infrared divergences in the two-dimensional non-linear σ models , 1981 .

[11]  S. Elitzur The Applicability of Perturbation Expansion to Two-dimensional Goldstone Systems , 1983 .

[12]  C. Itzykson,et al.  Functional methods and perturbation theory , 1975 .

[13]  Non-perturbative effects in two-dimensional lattice O(N) models , 1981 .

[14]  Current conservation in perturbation theory for the non-linear O(N) sigma model , 1981 .

[15]  G. Parisi On the relation between the renormalized and the bare coupling constant on the lattice , 1980 .

[16]  J. Lowenstein Differential vertex operations in Lagrangian field theory , 1971 .

[17]  S. Coleman There are no Goldstone bosons in two dimensions , 1973 .

[18]  D. Amit,et al.  The O(n)-symmetric model between two and four dimensions , 1981 .

[19]  Improving the lattice action near the continuum limit , 1982 .