Strings in flat space and pp waves from N = 4 Super Yang Mills

Abstract

We explain how the string spectrum in flat space and pp‐waves arises from the large N limit, at fixed gYM2, of U(N) N = 4 super Yang Mills. We reproduce the spectrum by summing a subset of the planar Feynman diagrams. We give a heuristic argument for why we can neglect other diagrams.