138 research outputs found
B-type defects in Landau-Ginzburg models
We consider Landau-Ginzburg models with possibly different superpotentials
glued together along one-dimensional defect lines. Defects preserving B-type
supersymmetry can be represented by matrix factorisations of the difference of
the superpotentials. The composition of these defects and their action on
B-type boundary conditions is described in this framework. The cases of
Landau-Ginzburg models with superpotential W=X^d and W=X^d+Z^2 are analysed in
detail, and the results are compared to the CFT treatment of defects in N=2
superconformal minimal models to which these Landau-Ginzburg models flow in the
IR.Comment: 50 pages, 2 figure
Integrability of the N=2 boundary sine-Gordon model
We construct a boundary Lagrangian for the N=2 supersymmetric sine-Gordon
model which preserves (B-type) supersymmetry and integrability to all orders in
the bulk coupling constant g. The supersymmetry constraint is expressed in
terms of matrix factorisations.Comment: LaTeX, 19 pages, no figures; v2: title changed, minor improvements,
refs added, to appear in J. Phys. A: Math. Ge
Current-Current Deformations of Conformal Field Theories, and WZW Models
Moduli spaces of conformal field theories corresponding to current-current
deformations are discussed. For WZW models, CFT and sigma model considerations
are compared. It is shown that current-current deformed WZW models have
WZW-like sigma model descriptions with non-bi-invariant metrics, additional
B-fields and a non-trivial dilaton.Comment: 30 pages, latex, v2: remarks and references adde
Defect Perturbations in Landau-Ginzburg Models
Perturbations of B-type defects in Landau-Ginzburg models are considered. In
particular, the effect of perturbations of defects on their fusion is analyzed
in the framework of matrix factorizations. As an application, it is discussed
how fusion with perturbed defects induces perturbations on boundary conditions.
It is shown that in some classes of models all boundary perturbations can be
obtained in this way. Moreover, a universal class of perturbed defects is
constructed, whose fusion under certain conditions obey braid relations. The
functors obtained by fusing these defects with boundary conditions are twist
functors as introduced in the work of Seidel and Thomas.Comment: 46 page
Defects and Bulk Perturbations of Boundary Landau-Ginzburg Orbifolds
We propose defect lines as a useful tool to study bulk perturbations of
conformal field theories, in particular to analyse the induced renormalisation
group flows of boundary conditions. As a concrete example we investigate bulk
perturbations of N=2 supersymmetric minimal models. To these perturbations we
associate a special class of defects between the respective UV and IR theories,
whose fusion with boundary conditions indeed reproduces the behaviour of the
latter under the corresponding RG flows. v2: Some explanations added in section
4, minor changes.Comment: 37 pages, 6 figure
Boundary conditions in Toda theories and minimal models
We show that the disc bulk one-point functions in a sl(n) Toda conformal
field theory have a well-defined limit for the central charge c=n-1, and that
their limiting values can be obtained from a limit of bulk one-point functions
in the W_n minimal models. This comparison leads to a proposal for one-point
functions for twisted boundary conditions in Toda theory.Comment: 33 pages, 1 figure; v2: Minor corrections; v3: version accepted at
JHE
Targeting sequences of the two major peroxisomal proteins in the methylotrophic yeast Hansenula polymorpha
Partition Functions of Holographic Minimal Models
The partition function of the W_N minimal model CFT is computed in the large
N 't Hooft limit and compared to the spectrum of the proposed holographic dual,
a 3d higher spin gravity theory coupled to massive scalar fields. At finite N,
the CFT contains additional light states that are not visible in the
perturbative gravity theory. We carefully define the large N limit, and give
evidence that, at N = infinity, the additional states become null and decouple
from all correlation functions. The surviving states are shown to match
precisely (for all values of the 't Hooft coupling) with the spectrum of the
higher spin gravity theory. The agreement between bulk and boundary is
partially explained by symmetry considerations involving the conjectured
equivalence between the W_N algebra in the large N limit and the higher spin
algebra of the Vasiliev theory.Comment: 56 page
Development of crystalline peroxisomes in methanol-grown cells of the yeast Hansenula polymorpha and its relation to environmental conditions
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