منابع مشابه
Matrix Compactification On Orientifolds
Generalizing previous results for orbifolds, in this paper we describe the compactification of Matrix model on an orientifold which is a quotient space R/Γ as a Yang-Mills theory living on a quantum space. The information of the compactification is encoded in the action of the discrete symmetry group Γ on Euclidean space Rd and a projective representation U of Γ. The choice of Hilbert space on ...
متن کاملComments on Orientifolds without Vector Structure
We revisit type I compactifications with a Spin(32)/Z2 gauge bundle that admits no vector structure. We elucidate the relation of this Z2 obstruction to discrete B-field flux and to ’t Hooft flux and clarify some subtleties in the T-duality transformation to type IIA intersecting D-brane models. We reexamine the earliest 3-generation GUT model on magnetized D-branes and show its consistency whe...
متن کاملF Theory Orientifolds, M Theory Orientifolds, and Twisted Strings
Orientifolds of the type IIB superstring that descend from F theory and M theory orbifolds are studied perturbatively. One finds strong evidence that a previously ignored twisted open string is required in these models. An attempt is made to interpret the J type torsion in F theory where one finds a realization of Gimon and Johnson’s models which does not require these twisted strings. S-dualit...
متن کاملPermutation Orientifolds
We consider orientifold actions involving the permutation of two identical factor theories. The corresponding crosscap states are constructed in rational conformal field theory. We study group manifolds, in particular the examples SU(2)×SU(2) and U(1)×U(1) in detail, comparing conformal field theory results with geometry. We then consider orientifolds of tensor products of N = 2 minimal models,...
متن کاملNotes on discrete torsion in orientifolds
In this short note we discuss discrete torsion in orientifolds. In particular, we apply the physical understanding of discrete torsion worked out several years ago, as group actions on B fields, to the case of orientifolds, and recover some old results of Braun and Stefanski concerning group cohomology and twisted equivariant K theory. We also derive new results including phase factors for nono...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Physical Review D
سال: 1996
ISSN: 0556-2821,1089-4918
DOI: 10.1103/physrevd.54.1647