Superconnections, anomalies and nonBPS brane charges

Aug, 2001
54 pages
Published in:
  • J.Geom.Phys. 43 (2002) 241-292
e-Print:
Report number:
  • HWM-01-31,
  • NBI-HE-00-07,
  • EMPG-01-11

Citations per year

2001200720132019202301234
Abstract:
The properties of brane-antibrane systems and systems of unstable D-branes in Type II superstring theory are investigated using the formalism of superconnections. The low-energy open string dynamics is shown to be probed by generalized Dirac operators. The corresponding index theorems are used to compute the chiral gauge anomalies in these systems, and hence their gravitational and Ramond-Ramond couplings. A spectral action for the generalized Dirac operators is also computed and shown to exhibit precisely the expected processes of tachyon condensation on the brane worldvolumes. The Chern-Simons couplings are thereby shown to be naturally related to Fredholm modules and bivariant K-theory, confirming the expectations that D-brane charge is properly classified by K-homology.
Note:
  • 57 pages LaTeX; Typos corrected, references added, various clarifying comments on derivations of superconnection actions in section 3 added Report-no: HWM-01-31, NBI-HE-00-07, EMPG-01-11 Subj-class: High Energy Physics - Theory; Mathematical Physics; K-Theory and Homology
  • membrane model
  • anomaly
  • string model
  • supersymmetry
  • index theorem
  • operator: Dirac
  • K-theory
  • tachyon: condensation
  • dimensional reduction
  • Chern-Simons term