The ten-dimensional effective action of strongly coupled heterotic string theory

We derive the ten-dimensional effective action of the strongly coupled hete rotic string as the low-energy limit of M-theory on S-1/Z(2). In contrast t o a conventional dimensional reduction, it is necessary to integrate out no n-trivial heavy modes which arise from the sources located on the orbifold fixed hyperplanes. This procedure, characteristic of theories with dynamica l boundaries, is illustrated by a simple example. Using this method, we det ermine a complete set of R-4, (FR2)-R-2, and F-4 terms and the correspondin g Chem-Simons and Green-Schwarz terms in ten dimensions. As required by ano maly cancellation and supersymmetry, these terms are found to exactly coinc ide with their weakly coupled one-loop counterparts. (C) 1999 Published by Elsevier Science B.V.