Results 11  20
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151
Dbranes in Gepner models
, 1997
"... We discuss Dbranes from a conformal field theory point of view. In this approach, branes are described by boundary states providing sources for closed string modes, independently of classical notions. The boundary states must satisfy constraints which fall into two classes: The first consists of gl ..."
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Cited by 58 (4 self)
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We discuss Dbranes from a conformal field theory point of view. In this approach, branes are described by boundary states providing sources for closed string modes, independently of classical notions. The boundary states must satisfy constraints which fall into two classes: The first consists of gluing conditions between leftand rightmoving Virasoro or further symmetry generators, whereas the second encompasses nonlinear consistency conditions from world sheet duality, which severely restrict the allowed boundary states. We exploit these conditions to give explicit formulas for boundary states in Gepner models, thereby computing excitation spectra of brane configurations. From the boundary states, brane tensions and RR charges can also be read off directly.
∗Trek II: ∗n operations, open Wilson lines and the SeibergWitten map
, 2000
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Noncommutative Worldvolume Geometries: Branes on SU(2) and Fuzzy Spheres
, 1999
"... The geometry of Dbranes can be probed by open string scattering. If the background carries a nonvanishing Bfield, the worldvolume becomes noncommutative. Here we explore the quantization of worldvolume geometries in a curved background with nonzero NeveuSchwarz 3form field strength H = dB. ..."
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Cited by 48 (8 self)
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The geometry of Dbranes can be probed by open string scattering. If the background carries a nonvanishing Bfield, the worldvolume becomes noncommutative. Here we explore the quantization of worldvolume geometries in a curved background with nonzero NeveuSchwarz 3form field strength H = dB. Using exact and generally applicable methods from boundary conformal field theory, we study the example of open strings in the SU(2) WessZuminoWitten model, and establish a relation with fuzzy spheres or certain (nonassociative) deformations thereof. These findings could be of direct relevance for Dbranes in the presence of NeveuSchwarz 5branes; more importantly, they provide insight into a completely new class of worldvolume geometries.
On theories with lightlike noncommutativity
 JHEP
"... We show that field theories with lightlike noncommutativity, that is with θ0i = −θ1i, are unitary quantum theories, and that they can be obtained as decoupled field theory limits of string theory with Dbranes in a background NSNS B field. For general noncommutativity parameters, we show that nonc ..."
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Cited by 45 (0 self)
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We show that field theories with lightlike noncommutativity, that is with θ0i = −θ1i, are unitary quantum theories, and that they can be obtained as decoupled field theory limits of string theory with Dbranes in a background NSNS B field. For general noncommutativity parameters, we show that noncommutative field theories which are unitary can be obtained as decoupled field theory limits of string theory, while those that are not unitary cannot be obtained from string theory because massive open strings do not decouple. We study the different theories with lightlike noncommutativity which arise from Type II Dbranes. The decoupling limit of the D4brane seems to lead to a noncommutative field theory deformation of the (2, 0) SCFT of M5branes, while the D5brane case leads to a noncommutative variation of “little string theories”. We discuss the DLCQ description of these theories. June
2001c, How noncommutative gauge theories couple to gravity, Nucl
 Phys. B599
"... We study coupling of noncommutative gauge theories on branes to closed string in the bulk. We derive an expression for the gauge theory operator dual to the bulk graviton, both in bosonic string theory and superstring theory. In either case, we find that the coupling is different from what was expec ..."
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Cited by 42 (5 self)
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We study coupling of noncommutative gauge theories on branes to closed string in the bulk. We derive an expression for the gauge theory operator dual to the bulk graviton, both in bosonic string theory and superstring theory. In either case, we find that the coupling is different from what was expected in the literature when the graviton is polarized in the noncommutative directions. In the case of superstring, the expression for the energymomentum tensor is consistent with the way the bulk metric appears in the action for the noncommutative gauge theory. We also clarify some aspects of the correspondence between operators in the gauge theory and boundary conditions in the Noncommutative gauge theories can be realized as the zero slope limit of open string theory on branes in a background of strong NSNS twoform field Bij [1 11]. It was pointed out in [12, 13] that, for each local observable in a gauge theory in commutative space, one can define an observable in the noncommutative version of the theory. The
Stretched strings in noncommutative field theory,” Phys. Rev. D 62 (2000) 066003 [arXiv:hepth/0004013
 H. Liu 62 J. Michelson, “*Trek: The oneloop N = 4 noncommutative SYM action,” Nucl. Phys. B
"... Preprint typeset in JHEP style. HYPER VERSION hepth/0004013 ..."
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Cited by 24 (4 self)
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Preprint typeset in JHEP style. HYPER VERSION hepth/0004013
Gauge bundles and BornInfeld on the noncommutative torus,” Nucl. Phys. B547
, 1999
"... In this paper, we describe nonabelian gauge bundles with magnetic and electric fluxes on higher dimensional noncommutative tori. We give an explicit construction of a large class of bundles with nonzero magnetic ’t Hooft fluxes. We discuss Morita equivalence between these bundles. The action of the ..."
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Cited by 23 (0 self)
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In this paper, we describe nonabelian gauge bundles with magnetic and electric fluxes on higher dimensional noncommutative tori. We give an explicit construction of a large class of bundles with nonzero magnetic ’t Hooft fluxes. We discuss Morita equivalence between these bundles. The action of the duality is worked out in detail for the fourtorus. As an application, we discuss BornInfeld on this torus, as a description of compactified string theory. We show that the resulting theory, including the fluctuations, is manifestly invariant under the Tduality group SO(4, 4; Z). The Uduality invariant BPS massformula is discussed shortly. We comment on a discrepancy of this result with that of a recent calculation. 1
Matrix theory on noncommutative torus
, 1998
"... We consider the compactification of Matrix theory on tori with background antisymmetric tensor field. Douglas and Hull have recently discussed how noncommutative geometry appears on the tori. In this paper, we demonstrate the concrete construction of this compactification of Matrix theory in a simil ..."
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Cited by 22 (0 self)
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We consider the compactification of Matrix theory on tori with background antisymmetric tensor field. Douglas and Hull have recently discussed how noncommutative geometry appears on the tori. In this paper, we demonstrate the concrete construction of this compactification of Matrix theory in a similar way to that previously given by Taylor. March