Non-renormalization theorems in Type-II string theory and maximal supergravity

by Russo, J. (ICREA, Univ. Barcelona)

Monday 5 Feb 2007, 14:00 → 15:00 Europe/Zurich

TH Auditorium (CERN)

Assuming the standard M-theory/string theory duality relationships, one can obtain powerful constraints on the possible structure of higher derivative terms in the type-II effective action. In the ten-dimensional IIA limit, we find that a term D2kR4 does not receive any perturbative contributions beyond k string loops (for any k > 0). Furthermore, the maximum genus h = k contributions are determined exactly by the one-loop eleven-dimensional supergravity amplitude. A plausible interpretation of these observations is that the sum of h-loop Feynman diagrams of maximally extended supergravity is less divergent than might be expected and could be ultraviolet finite in dimensions d < 4+6/h - the same bound as for N=4 Yang-Mills.


Note: Please note unusual day