Abstract :
The universal hypermultiplet arises as a subsector of every Calabi–Yau compactification of M-theory of type II string theory. Classically its moduli space is the quaternionic space SU(2,1)/U(2) . we show that this moduli space receives a one-loop correction proportional to the Euler character of the Calabi–Yau, which can locally be absorbed by a certain constant shift of the fields. The correction vanishes in the limit that the Planck mass is taken to infinity, and hence is essentially gravitational in nature.
