Massless Scalar Field Theory in a Quantised Space-Time

Abstract

A method is developed to construct a non-local massless scalar field theory in a flat quantised space-time generated by an operator algebra. Implicit in the operator algebra is a fundamental length scale of the space-time. The fundamental two-point function of free fields is constructed by assuming that the causal Green functions still have support on the light cone in the operator algebra quantised space-time. In contrast to previous stochastic approaches, the method introduced here requires no explicit averaging over spacetime coordinates. The two- and four-point functions of~$g \varphi^4$ theory are calculated to the one-loop level, and no ultraviolet divergences are encountered. It is also demonstrated that there are no IR divergences in the processes considered.