11TH-ORDER CALCULATION OF ISING-LIMIT GREENS-FUNCTIONS FOR SCALAR QUANTUM-FIELD THEORY IN ARBITRARY SPACE-TIME DIMENSION-D

This paper extends an earlier high-temperature lattice calculation of the renormalized Greens function of a D-dimensional Euclidean scalar quantum field theory in the Ising limit. The previous calculation included all graphs through sixth order. Here, we present the results of an eleventh-order calculation. The extrapolation to the continuum limit in the previous calculation was rather clumsy and did not appear to converge when D>2. Here, we present an improved extrapolation which gives uniformly good results for all real values of the dimension between D=0 and D=4. We find that the four-point Greens function has the value 0.6200.007 when D=2 and 0.980.01 when D=3 and that the six-point Greens function has the value 0.960.03 when D=2 and 1.20.2 when D=3. © 1995 The American Physical Society.