Dirichlet Branes and RamondRamond Charges
Abstract
We show that Dbranes, extended objects defined by mixed DirichletNeumann boundary conditions, break half the supersymmetries of the type II superstring and carry a complete set of electric and magnetic RamondRamond charges. The product of the electric and magnetic charges is a single Dirac unit, and the quantum of charge is that required by string duality. This is strong evidence that Dbranes are intrinsic to type II string theory and are the RamondRamond sources needed for string duality. Also, we find in the IIa string a 9form potential, which gives an effective cosmological constant.
 Publication:

Physical Review Letters
 Pub Date:
 December 1995
 DOI:
 10.1103/PhysRevLett.75.4724
 arXiv:
 arXiv:hepth/9510017
 Bibcode:
 1995PhRvL..75.4724P
 Keywords:

 High Energy Physics  Theory
 EPrint:
 LaTeX, 10 pages. Minor typos corrected in eq. 8, 9, 13. References added to [11]