765 research outputs found
D-branes in Unoriented Non-critical Strings and Duality in SO(N) and Sp(N) Gauge Theories
We exhibit exact conformal field theory descriptions of SO(N) and Sp(N) pairs
of Seiberg-dual gauge theories within string theory. The N=1 gauge theories
with flavour are realized as low energy limits of the worldvolume theories on
D-branes in unoriented non-critical superstring backgrounds. These unoriented
backgrounds are obtained by constructing exact crosscap states in the
SL(2,R)/U(1) coset conformal field theory using the modular bootstrap method.
Seiberg duality is understood by studying the behaviour of the boundary and
crosscap states under monodromy in the closed string parameter space.Comment: 23 pages, 2 figure
On supersymmetry breaking in string theory from gauge theory in a throat
We embed the supersymmetry breaking mechanism in N=1 SQCD of hep-th/0602239
in a smooth superstring theory using D-branes in the background R^4 \times
SL(2)_{k=1}/U(1) which smoothly captures the throat region of an intersecting
NS5-brane configuration. A controllable deformation of the supersymmetric
branes gives rise to the mass deformation of the magnetic SQCD theory on the
branes. The consequent instability on the open string worldsheet can be
followed onto a stable non-supersymmetric configuration of D-branes which
realize the metastable vacuum configuration in the field theory. The new brane
configuration is shown to backreact onto the background such as to produce
different boundary conditions for the string fields in the radial direction
compared to the supersymmetric configuration. In the string theory, this is
interpreted to mean that the supersymmetry breaking is explicit rather than
spontaneous.Comment: 29 pages, harvmac, 8 figures; v2 typos corrected, reference adde
Effective superpotential for U(N) with antisymmetric matter
We consider an N=1 U(N) gauge theory with matter in the antisymmetric
representation and its conjugate, with a tree level superpotential containing
at least quartic interactions for these fields. We obtain the effective
glueball superpotential in the classically unbroken case, and show that it has
a non-trivial N-dependence which does not factorize. We also recover additional
contributions starting at order S^N from the dynamics of Sp(0) factors. This
can also be understood by a precise map of this theory to an Sp(2N-2) gauge
theory with antisymmetric matter.Comment: 22 pages. v2: comment (and a reference) added at the end of section 2
on low rank cases; minor typos corrected. v3: 2 footnotes added with
additional clarifications; version to appear in journa
Constructing Gauge Theory Geometries from Matrix Models
We use the matrix model -- gauge theory correspondence of Dijkgraaf and Vafa
in order to construct the geometry encoding the exact gaugino condensate
superpotential for the N=1 U(N) gauge theory with adjoint and symmetric or
anti-symmetric matter, broken by a tree level superpotential to a product
subgroup involving U(N_i) and SO(N_i) or Sp(N_i/2) factors. The relevant
geometry is encoded by a non-hyperelliptic Riemann surface, which we extract
from the exact loop equations. We also show that O(1/N) corrections can be
extracted from a logarithmic deformation of this surface. The loop equations
contain explicitly subleading terms of order 1/N, which encode information of
string theory on an orientifolded local quiver geometry.Comment: 52 page
Topological Cigar and the c=1 String : Open and Closed
We clarify some aspects of the map between the c=1 string theory at self-dual
radius and the topologically twisted cigar at level one. We map the ZZ and FZZT
D-branes in the c=1 string theory at self dual radius to the localized and
extended branes in the topological theory on the cigar. We show that the open
string spectrum on the branes in the two theories are in correspondence with
each other, and their two point correlators are equal. We also find a
representation of an extended N=2 algebra on the worldsheet which incorporates
higher spin currents in terms of asymptotic variables on the cigar.Comment: 37 pages, 2 figures, corrections to section 3.1, references adde
Kac and New Determinants for Fractional Superconformal Algebras
We derive the Kac and new determinant formulae for an arbitrary (integer)
level fractional superconformal algebra using the BRST cohomology
techniques developed in conformal field theory. In particular, we reproduce the
Kac determinants for the Virasoro () and superconformal () algebras.
For there always exist modules where the Kac determinant factorizes
into a product of more fundamental new determinants. Using our results for
general , we sketch the non-unitarity proof for the minimal series;
as expected, the only unitary models are those already known from the coset
construction. We apply the Kac determinant formulae for the spin-4/3
parafermion current algebra ({\em i.e.}, the fractional superconformal
algebra) to the recently constructed three-dimensional flat Minkowski
space-time representation of the spin-4/3 fractional superstring. We prove the
no-ghost theorem for the space-time bosonic sector of this theory; that is, its
physical spectrum is free of negative-norm states.Comment: 33 pages, Revtex 3.0, Cornell preprint CLNS 93/124
Phases of N=1 Supersymmetric SO/Sp Gauge Theories via Matrix Model
We extend the results of Cachazo, Seiberg and Witten to N=1 supersymmetric
gauge theories with gauge groups SO(2N), SO(2N+1) and Sp(2N). By taking the
superpotential which is an arbitrary polynomial of adjoint matter \Phi as a
small perturbation of N=2 gauge theories, we examine the singular points
preserving N=1 supersymmetry in the moduli space where mutually local monopoles
become massless. We derive the matrix model complex curve for the whole range
of the degree of perturbed superpotential. Then we determine a generalized
Konishi anomaly equation implying the orientifold contribution. We turn to the
multiplication map and the confinement index K and describe both Coulomb branch
and confining branch. In particular, we construct a multiplication map from
SO(2N+1) to SO(2KN-K+2) where K is an even integer as well as a multiplication
map from SO(2N) to SO(2KN-2K+2) (K is a positive integer), a map from SO(2N+1)
to SO(2KN-K+2) (K is an odd integer) and a map from Sp(2N) to Sp(2KN+2K-2).
Finally we analyze some examples which show some duality: the same moduli space
has two different semiclassical limits corresponding to distinct gauge groups.Comment: 55pp; two paragraphs in page 19 added to clarify the relation between
confinement index and multiplication map index, refs added and to appear in
JHEP; Konishi anomaly equations corrected and some comments on the
degenerated cases for SO(7) and SO(8) adde
Note on Matrix Model with Massless Flavors
In this note, following the work of Seiberg in hep-th/0211234 for the
conjecture between the field theory and matrix model in the case with massive
fundamental flavors, we generalize it to the case with massless fundamental
flavors. We show that with a little modifications, the analysis given by
Seiberg can be used directly to the case of massless flavors. Furthermore, this
new method explains the insertion of delta functions in the matrix model given
by Demasure and Janik in hep-th/0211082.Comment: 10 pages. Type fixed. Remarks adde
Chiral rings, anomalies and loop equations in N=1* gauge theories
We examine the equivalence between the Konishi anomaly equations and the
matrix model loop equations in N=1* gauge theories, the mass deformation of N=4
supersymmetric Yang-Mills. We perform the superfunctional integral of two
adjoint chiral superfields to obtain an effective N=1 theory of the third
adjoint chiral superfield. By choosing an appropriate holomorphic variation,
the Konishi anomaly equations correctly reproduce the loop equations in the
corresponding three-matrix model. We write down the field theory loop equations
explicitly by using a noncommutative product of resolvents peculiar to N=1*
theories. The field theory resolvents are identified with those in the matrix
model in the same manner as for the generic N=1 gauge theories. We cover all
the classical gauge groups. In SO/Sp cases, both the one-loop holomorphic
potential and the Konishi anomaly term involve twisting of index loops to
change a one-loop oriented diagram to an unoriented diagram. The field theory
loop equations for these cases show certain inhomogeneous terms suggesting the
matrix model loop equations for the RP2 resolvent.Comment: 23 pages, 3 figures, latex2e, v4: minor changes in introduction and
conclusions, 4 references are added, version to appear in JHE
Improved matrix-model calculation of the N=2 prepotential
We present a matrix-model expression for the sum of instanton contributions
to the prepotential of an N=2 supersymmetric U(N) gauge theory, with matter in
various representations. This expression is derived by combining the
renormalization-group approach to the gauge theory prepotential with
matrix-model methods. This result can be evaluated order-by-order in
matrix-model perturbation theory to obtain the instanton corrections to the
prepotential. We also show, using this expression, that the one-instanton
prepotential assumes a universal form.Comment: 20 pages, LaTeX, 2 figure
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