Tr. Morris, 3-DIMENSIONAL MASSIVE SCALAR FIELD-THEORY AND THE DERIVATIVE EXPANSION OF THE RENORMALIZATION-GROUP, Nuclear physics. B, 495(3), 1997, pp. 477-504
We show that non-perturbative fixed points of the exact renormalizatio
n group, their perturbations and corresponding massive field theories
can all be determined directly in the continuum - without using bare a
ctions or any tuning procedure. As an example, we estimate the univers
al couplings of the non-perturbative three-dimensional one-component m
assive scalar field theory in the Ising model universality class, by u
sing a derivative expansion (and no other approximation). These are co
mpared to the recent results from other methods. At order derivative-s
quared approximation, the four-point coupling at zero momentum is bett
er determined by other methods, but factoring this out appropriately,
all our other results are in very close agreement with the most powerf
ul of these methods. In addition we provide for the first time, estima
tes of the n-point couplings at zero momentum, with n = 12, 14, and th
e order momentum-squared parts with n = 2,..., 10. (C) 1997 Elsevier S
cience B.V.