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Anomalies in string theory with D-branes
We analyze global anomalies for elementary Type II strings in the presence of D-branes. Global anomaly cancellation gives a restriction on the D-brane topology. This restriction makes possible theExpand
Instantons and Four-Manifolds
This volume has been designed to explore the confluence of techniques and ideas from mathematical physics and the topological study of the differentiable structure of compact four-dimensionalExpand
The analysis of elliptic families
In this paper we specialize the results obtained in [BF1] to the case of a family of Dirac operators. We first calculate the curvature of the unitary connection on the determinant bundle which weExpand
Loop groups and twisted K-theory I
This is the first in a series of papers investigating the relationship between the twisted equivariant K-theory of a compact Lie group G and the “Verlinde ring” of its loop group. In this paper weExpand
Twisted Equivariant Matter
We show how general principles of symmetry in quantum mechanics lead to twisted notions of a group representation. This framework generalizes both the classical threefold way of real/complex/Expand
Reflection positivity and invertible topological phases
We implement an extended version of reflection positivity (Wick-rotated unitarity) for invertible topological quantum field theories and compute the abelian group of deformation classes using stableExpand
The geometry of loop groups
L'espace ΩG des boucles basees sur un groupe de Lie compact admet une metrique de Kahler. On exprime sa courbure en termes d'operateurs de Toeplitz et on definit des classes de Chern par analogieExpand
η‐invariants and determinant lines
The η‐invariant of an odd dimensional manifold with boundary is investigated. The natural boundary condition for this problem requires a trivialization of the kernel of the Dirac operator on theExpand
Higher algebraic structures and quantization
  • D. Freed
  • Physics, Mathematics
  • 18 December 1992
We derive (quasi-)quantum groups in 2+1 dimensional topological field theory directly from the classical action and the path integral. Detailed computations are carried out for the Chern-SimonsExpand
Dirac Charge Quantization and Generalized Differential Cohomology
  • D. Freed
  • Physics, Mathematics
  • 24 November 2000
The main new result here is the cancellation of global anomalies in the Type I superstring, with and without D-branes. Our argument here depends on a precise interpretation of the 2-form abelianExpand