Flory exponents from a self-consistent renormalization group

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