StrongWeak Coupling Duality in FourDimensional String Theory
Abstract
We present several pieces of evidence for strongweak coupling duality symmetry in the heterotic string theory, compactified on a sixdimensional torus. They include symmetry of the (1) low energy effective action, (2) allowed spectrum of electric and magnetic charges in the theory, (3) allowed mass spectrum of particles saturating the Bogomol'nyi bound, and (4) Yukawa couplings between massless neutral particles and massive charged particles saturating the Bogomol'nyi bound.
This duality transformation exchanges the electrically charged elementary string excitations with the magnetically charged soliton states in the theory. It is shown that the existence of a strongweak coupling duality symmetry in fourdimensional string theory makes definite predictions about the existence of new stable monopole and dyon states in the theory with specific degeneracies, including certain supersymmetric bound states of monopoles and dyons. The relationship between strongweak coupling duality transformation in string theory and target space duality transformation in the fivebrane theory is also discussed.
 Publication:

International Journal of Modern Physics A
 Pub Date:
 1994
 DOI:
 10.1142/S0217751X94001497
 arXiv:
 arXiv:hepth/9402002
 Bibcode:
 1994IJMPA...9.3707S
 Keywords:

 High Energy Physics  Theory
 EPrint:
 LATEX, 42 pages, TIFR/TH/9403 (missing terms in eq.(81) (section 5) have been added)