Flory exponents from a self-consistent renormalization group

The wandering exponent u for an isotropic polymer is predicted remarkably well by a simple argument due to Flory. By considering oriented polymers living in a oneparameter farniy of background tangent fields, we are able to relate the wandering exponent to the exponent in the background field through an e-expansion. We then choose the background field to have the same correlations as the individual polymer, thus self-consistently solving for u. We find u = 3/(d + 2) for d < 4 and u = 1/2 for d > 4, which is exactly the Flory result.