Triangle Seminars
Monday, 23 Feb 2009
Dimer Models and Calabi-Yau Algebras
Nathan Broomhead
(Bath University)
Abstract:
From dimer models, as introduced in string theory, we can
produce a class of Calabi Yau algebras which are candidates for non-commutative crepant resolutions of Gorenstein 3 fold affine toric singularities. In this talk I will introduce, via examples, dimers and their corresponding toric varieties. I will then talk about the consistency condition that underlies the Calabi Yau property.
From dimer models, as introduced in string theory, we can
produce a class of Calabi Yau algebras which are candidates for non-commutative crepant resolutions of Gorenstein 3 fold affine toric singularities. In this talk I will introduce, via examples, dimers and their corresponding toric varieties. I will then talk about the consistency condition that underlies the Calabi Yau property.
Posted by: IC
Tuesday, 24 Feb 2009
Towards the solution of the spectral problem of the planar AdF/CFT correspondence
Adam Rej
(Imperial College London)
Abstract:
In this talk we will review the recent developments in the field of integrability of the AdS/CFT correspondence. In particular, we will discuss the novel dynamical tests of the duality and summarize the breakdown of the asymptotic spin-chain picture at the wrapping order. We will also discuss the latest attempts to incorporate the non-local wrapping interactions.
In this talk we will review the recent developments in the field of integrability of the AdS/CFT correspondence. In particular, we will discuss the novel dynamical tests of the duality and summarize the breakdown of the asymptotic spin-chain picture at the wrapping order. We will also discuss the latest attempts to incorporate the non-local wrapping interactions.
Posted by: KCL
Wednesday, 25 Feb 2009
TBA
Pau Figueras
(Durham)
Non-planar ABJM Theory, Integrability and Parity
Charlotte Kristjansen
(NBI)
Abstract:
First we review existing results concerning the non-planar spectrum of
N=4 SYM. Next, using an effective vertex method we explicitly
derive the two-loop dilatation generator of ABJM theory in its
SU(2) x SU(2) sector, including all non-planar corrections. This
generator is then applied to a series of finite length operators as well
as to two different types of BMN operators. As in N=4 SYM, at the
planar level the finite length operators are found to exhibit a degeneracy
between certain pairs of operators with opposite parity – a degeneracy
which can be attributed to the existence of an extra conserved charge and
thus to the integrability of the planar theory.When non-planar corrections
are taken into account the degeneracies between parity pairs disappear
hinting the absence of higher conserved charges. The analysis of the BMN
operators resembles that of N=4 SYM. Additional non-planar terms
appear for BMN operators of finite length but once the strict BMN limit is
taken these terms disappear.
First we review existing results concerning the non-planar spectrum of
N=4 SYM. Next, using an effective vertex method we explicitly
derive the two-loop dilatation generator of ABJM theory in its
SU(2) x SU(2) sector, including all non-planar corrections. This
generator is then applied to a series of finite length operators as well
as to two different types of BMN operators. As in N=4 SYM, at the
planar level the finite length operators are found to exhibit a degeneracy
between certain pairs of operators with opposite parity – a degeneracy
which can be attributed to the existence of an extra conserved charge and
thus to the integrability of the planar theory.When non-planar corrections
are taken into account the degeneracies between parity pairs disappear
hinting the absence of higher conserved charges. The analysis of the BMN
operators resembles that of N=4 SYM. Additional non-planar terms
appear for BMN operators of finite length but once the strict BMN limit is
taken these terms disappear.
Posted by: KCL
D-branes and matrix factorisations in supersymmetric coset models
Stefan Fredenhagen
(AEI Potsdam)
Abstract:
In Landau-Ginzburg models, B-type boundary conditions are described by matrix factorisations of the superpotential. In cases where such a model corresponds to a rational conformal field theory (e.g. a coset model), we can compare the matrix factorisations to known boundary states. The connection between these complementary descriptions can on the one hand be used to improve the understanding of closed and open string moduli space, on the other hand it could give hints towards the construction of new boundary states.
In Landau-Ginzburg models, B-type boundary conditions are described by matrix factorisations of the superpotential. In cases where such a model corresponds to a rational conformal field theory (e.g. a coset model), we can compare the matrix factorisations to known boundary states. The connection between these complementary descriptions can on the one hand be used to improve the understanding of closed and open string moduli space, on the other hand it could give hints towards the construction of new boundary states.
Posted by: KCL
Thursday, 26 Feb 2009
D-branes and giant gravitons in AdS4xCP3
Andrea Prinsloo
(University of Cape Town)
Abstract:
The AdS4/Chern-Simons theory duality, recently conjectured by Aharony, Bergman, Jafferis and Maldacena, provides not only a new testing ground for the gauge theory/gravity correspondence, but also a possible way to access M-theoretic degrees of freedom. In this talk, I shall discuss some of our recent results on the open string sector of the type IIA string theory in AdS4xCP3, with emphasis on D-branes and giant gravitons in particular. Specifically, I shall focus on the so-called dual giant, a D2-brane extended on an S2 in AdS4, its spectrum of small fluctuations and open strings attached to it.
The AdS4/Chern-Simons theory duality, recently conjectured by Aharony, Bergman, Jafferis and Maldacena, provides not only a new testing ground for the gauge theory/gravity correspondence, but also a possible way to access M-theoretic degrees of freedom. In this talk, I shall discuss some of our recent results on the open string sector of the type IIA string theory in AdS4xCP3, with emphasis on D-branes and giant gravitons in particular. Specifically, I shall focus on the so-called dual giant, a D2-brane extended on an S2 in AdS4, its spectrum of small fluctuations and open strings attached to it.
Posted by: QMW