Searcharxiv⌕ Search

arXiv subjects

Jaume Gomis

Publications and source records attributed to Jaume Gomis.

80 records · Page 5Linked to original sources
arXiv1999

Fractional Branes and Boundary States in Orbifold Theories

We study the D-brane spectrum of N=2 string orbifold theories using the boundary state formalism. The construction is carried out for orbifolds with isolated singularities, non-isolated singularities and orbifolds with discrete torsion. Our results agree with the corresponding K-theoretic predictions when they are available and generalize them when they are not. This suggests that the classification of boundary states provides a sort of "quantum K-theory" just as chiral rings in CFT provide "quantum" generalizations of cohomology. We discuss the identification of these states with D-branes wrapping holomorphic cycles in the large radius limit of the CFT moduli space. The example C^3/Z_3 is worked out in full detail using local mirror symmetry techniques. We find a precise correspondence between fractional branes at the orbifold point and configurations of D-branes described by vector bundles on the exceptional P^2 cycle.

hep-th↗
arXiv1998

Neveu-Schwarz Five-Branes at Orbifold Singularities and Holography

We consider Type IIB Neveu-Schwarz five-branes transverse to C^2/Z_n orbifolds and conjecture that string theory on the near horizon geometry is dual to the decoupled theory on the branes. We analyze the conformal field theory describing the near horizon region and the world volume non-critical string theory. The modular invariance consistency condition of string theory is exactly reproduced as the gauge anomaly cancellation condition in the little string theories. We comment on aspects of the holographic nature of this duality.

hep-th↗
arXiv1998

Spectrum of Chiral Operators in Strongly Coupled Gauge Theories

We analyze the large $N$ spectrum of chiral primary operators of three dimensional fixed points of the renormalization group. Using the space-time picture of the fixed points and the correspondence between anti-de Sitter compactifications and conformal field theories we are able to extract the dimensions of operators in short superconformal multiplets. We write down some of these operators in terms of short distance theories flowing to these non-trivial fixed points in the infrared.

hep-th↗
arXiv1998

Neveu-Schwarz Five-Branes And Matrix String Theory On K3

The Matrix theory description of Type IIA string theory on a compact K3 surface as the theory of Neveu-Schwarz five-branes on $\tilde{K3}\times S^1$ is analyzed. The full multiplet of space-time BPS states is identified in the five-brane world-volume as fluxes.

hep-th↗
arXiv1997

Fractional Branes and Wrapped Branes

We discuss the ``fractional D-branes'' which arise in orbifold resolution. We argue that they arise as subsectors of the Coulomb branch of the quiver gauge theory used to describe both string theory D-brane and Matrix theory on an orbifold, and thus must form part of the full physical Hilbert space. We make further observations confirming their interpretation as wrapped membranes.

hep-th↗
arXiv1997

Matrix Description of Heterotic Theory on K3

The Matrix description of certain $E_8\times E_8$ heterotic theories on $T^4/Z_2$ is shown to correspond to the world-volume theory of $Spin(32)/Z_2$ heterotic five-branes on the dual $T^4/Z_2\times S^1$.

hep-th↗
arXiv1997

Duality in Matrix Theory and Three Dimensional Mirror Symmetry

Certain limits of the duality between M-theory on ${T^5/Z_2}$ and IIB on K3 are analyzed in Matrix theory. The correspondence between M-theory five-branes and ALE backgrounds is realized as three dimensional mirror symmetry. Non-critical strings dual to open membranes are explicitly described as gauge theory excitations. We also comment on Type IIA on K3 and the appearance of gauge symmetry enhancement at special points in the moduli space.

hep-th↗