13 research outputs found
Classification of N=2 supersymmetric CFT_{4}s: Indefinite Series
Using geometric engineering method of 4D quiver gauge
theories and results on the classification of Kac-Moody (KM) algebras, we show
on explicit examples that there exist three sectors of infrared
CFTs. Since the geometric engineering of these CFTs involve type II
strings on K3 fibered CY3 singularities, we conjecture the existence of three
kinds of singular complex surfaces containing, in addition to the two standard
classes, a third indefinite set. To illustrate this hypothesis, we give
explicit examples of K3 surfaces with H and E hyperbolic
singularities. We also derive a hierarchy of indefinite complex algebraic
geometries based on affine and T algebras going beyond the
hyperbolic subset. Such hierarchical surfaces have a remarkable signature that
is manifested by the presence of poles.Comment: 12 pages, 2 figure
NC Calabi-Yau Orbifolds in Toric Varieties with Discrete Torsion
Using the algebraic geometric approach of Berenstein et {\it al}
(hep-th/005087 and hep-th/009209) and methods of toric geometry, we study non
commutative (NC) orbifolds of Calabi-Yau hypersurfaces in toric varieties with
discrete torsion. We first develop a new way of getting complex mirror
Calabi-Yau hypersurfaces in toric manifolds with a action and analyze the general group of the
discrete isometries of . Then we build a general class of
complex dimension NC mirror Calabi-Yau orbifolds where the non
commutativity parameters are solved in terms of discrete
torsion and toric geometry data of in which the original
Calabi-Yau hypersurfaces is embedded. Next we work out a generalization of the
NC algebra for generic dimensions NC Calabi-Yau manifolds and give various
representations depending on different choices of the Calabi-Yau toric geometry
data. We also study fractional D-branes at orbifold points. We refine and
extend the result for NC to higher dimensional torii orbifolds
in terms of Clifford algebra.Comment: 38 pages, Late
On Non Commutative G2 structure
Using an algebraic orbifold method, we present non-commutative aspects of
structure of seven dimensional real manifolds. We first develop and solve
the non commutativity parameter constraint equations defining manifold
algebras. We show that there are eight possible solutions for this extended
structure, one of which corresponds to the commutative case. Then we obtain a
matrix representation solving such algebras using combinatorial arguments. An
application to matrix model of M-theory is discussed.Comment: 16 pages, Latex. Typos corrected, minor changes. Version to appear in
J. Phys.A: Math.Gen.(2005