Functional Strong Coupling Theory
نویسنده
چکیده
The vacuum expectation value of the S-matrix is represented, following HORI, as a functional integral and separated according to 5Vac = exp( — i W) f D (p exp( —i / d x L w ) . Now, the functional integral involves only the part L w of the Lagrangian without derivatives and can be easily calculated in lattice space. We propose a graphical scheme which formalizes the action of the operator r = / dx dy <5(x — y) (ö/do(y)) Q j (^ / «5o (x ) ) . The scheme is worked out in some detail for the calculation of the two-point-function of neutral BOSE fields with the self-interaction / (pM for even M. A method is proposed which under certain convergence assumptions should yield in a finite number of steps the lowest mass eigenvalues and the related matrix elements. The method exhibits characteristic differences between renormalizable and nonrenormalizable theories.
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