Effective field theory, black holes, and the cosmological constant

Bekenstein has proposed the bound S less than or equal to pi (MPL2)-L-2 on the total entropy S in a volume L-3. This nonextensive scaling suggests tha t quantum field theory breaks down in large volume. To reconcile this break down with the success of local quantum field theory in describing observed particle phenomenology, we propose a relationship between UV and IR cutoffs such that an effective field theory should be a good description of nature . We discuss implications for the cosmological constant problem. We find a limitation on the accuracy which can be achieved by conventional effective field theory.