LOW ENERGY QUANTUM GRAVITY, THE COSMOLOGICAL CONSTANT AND GAUGE COUPLING CONSTANTS

Abstract

Robinson and Wilczek have suggested that loop corrections in quantum gravity can alter the running gauge coupling constants from the behaviour found in the absence of gravity. Although their original calculation is not correct, the basic idea behind their paper has been re-examined recently for quantized Einstein–Maxwell theory with a cosmological constant. In this essay I discuss some of the issues surrounding the calculation and mention some of the implications. I argue that it is possible for a theory that is not conventionally asymptotically free to become so in the presence of gravity, and for gravity to lead to a new ultraviolet fixed point. This establishes a provocative link between the microscopic and macroscopic realms.