Global Spinors and Orientable Five-Branes
نویسنده
چکیده
Fermion fields on an M-theory five-brane carry a representation of the double cover of the structure group of the normal bundle. It is shown that, on an arbitrary oriented Lorentzian six-manifold, there is always an Sp 2 twist that allows such spinors to be defined globally. The vanishing of the arising potential obstructions does not depend on spin structure in the bulk, nor does the six-manifold need to be spin or spin. Lifting the tangent bundle to such a generalised spin bundle requires picking a generalised spin structure in terms of certain elements in the integral and modulo-two cohomology of the five-brane world-volume in degrees four and five, respectively. PACS 11.25.-w
منابع مشابه
Modified Pure Spinors and Mirror Symmetry
It has been argued recently that mirror symmetry exchanges two pure spinors characterizing a generic manifold with SU(3)-structure. We show how pure spinors are modified in the presence of topological D-branes, so that they are still exchanged by mirror symmetry. This exchange emerges from the fact that the modified pure spinors come out as moment maps for the symmetries of A and B-models. The ...
متن کاملSurface observables and the Weyl anomaly
M -theory admits configurations with some number N of coincident five-branes embedded in a curved eleven-dimensional space. Small fluctuations around this configuration are described by a (0, 2) superconformal field theory defined on the six-dimensional world-volume M of the branes, and with a background metric Gμν given by the embedding. There is a conformally invariant observable W (Σ) associ...
متن کاملSuperstrings and D-branes in Plane Wave
We carefully analyze the supersymmetry algebra of closed strings and open strings in a plane wave. We use eight component chiral spinors, SO(8) Majorana-Weyl spinors, in lightcone gauge to provide a useful basis of string field theory calculation in the plane wave. We consider the two classes of half BPS D-branes, D±-branes, preserving 16 supersymmetries. We exhaustively provide the supersymmet...
متن کاملCurved Branes in AdS Einstein-Maxwell Gravity and Killing Spinors
We determine the Killing spinors for a class of magnetic brane solutions with Minkowski worldvolume of the theory of AdS Einstein Maxwell theories in d dimensions. We also obtain curved magnetic brane solutions with Ricci-flat worldvolumes. If we demand that the curved brane solution admits Killing spinors, then its worldvolume must admit parallel spinors. Classes of Ricci-flat worldvolumes adm...
متن کاملHolonomy from wrapped branes
Compactifications of M-theory on manifolds with reduced holonomy arise as the local eleven-dimensional description of D6-branes wrapped on supersymmetric cycles in manifolds of lower dimension with a different holonomy group. Whenever the isometry group SU(2) is present, eight-dimensional gauged supergravity is a natural arena for such investigations. In this paper we use this approach and revi...
متن کامل