Exact results in non-supersymmetric large N orientifold field theories

We consider non-supersymmetric large N orientifold field theories. Specifically, we discuss a gauge theory with a Dirac fermion in the antisymmetric tensor representation. We argue that, at large N and in a large part of its bosonic sector, this theory is nonperturbatively equivalent to N = 1 SYM, so that exact results established in the latter (parent) theory also hold in the daughter orientifold theory. In particular, the non-supersymmetric theory has an exactly calculable bifermion condensate, exactly degenerate parity doublets, and a vanishing cosmological constant (all this to leading order in 1/N). (C) 2003 Elsevier B.V. All rights reserved.