Using the Wegner-Houghton equation, within the local potential approximation, we study critical properties of O( N) vector models. Fixed points, together with their critical exponents and eigenoperators, are obtained for a large set of values of N, including N = 0 and N → ∞. Polchinski's equation is also treated. The peculiarities of the large N limit, where a line of Fixed Points at d = 2 + 2/ n is present, are studied in detail. A derivation of the equation is presented together with its projection to zero-modes.
Nuclear Physics B
- Pub Date:
- February 1997
- High Energy Physics - Theory;
- Condensed Matter - Statistical Mechanics;
- High Energy Physics - Lattice
- 27 pages, LaTeX with psfig, 7 PostScript figures. One reference corrected and one added with respect to the journal version