Quantum gravity, the Planck lattice and the Standard Model

Abstract

A possible ground state of Quantum Gravity is Wheeler's ``space-time foam'', which can be modeled as a ``Planck-lattice'', a space-time cubic lattice of lattice constant $a_P\simeq 10^{33}$cm, the Planck length. I analyse the structure of the Standard Model defined on the Planck Lattice, in the light of the ``no-go'' theorem of Nielsen and Ninomiya, which requires an extension of the continuum model through Nambu-Jona Lasinio terms, quadrilinear in the Fermi-fields. As a result, a theory of masses (of both fermions and gauge bosons) is seen to emerge that, without Higgs excitations, agrees well with observations.

Comments: Invited Talk at the ``VII Marcel Grossman Meeting on General Relativity'' - Stanford, July 1994. 14 pages, latex, five figures, which will be available upon request.