Triangle Seminars
Monday, 22 Oct 2007
Open/closed topological field theory and topological gravity
Ezra Getzler
(Northwestern University)
Abstract:
The lectures will start by reviewing closed topological theories, before moving to more recent work in the open/closed theory on spaces with boundary.
From the work of Witten, the topology of the so-called Deligne-Mumford moduli spaces of Riemann surfaces with nodes plays a fundamental role in 2-dimensional topological gravity (known to mathematicians as Gromov-Witten theory). For example, by the work of Kontsevich and Manin, it is seen to underly the Witten-Dijkgraaf-Verlinde-Verlinde equation, and hence is intimately related to the theory of Frobenius manifolds and of integrable systems.
Most work on these moduli spaces has been focussed on the case of closed topological field theory. In these lectures, I will explore the moduli spaces, analogous to Deligne-Mumford moduli spaces, which play the corresponding role in the open theory. In this case, the world sheet (Riemann surface) has a boundary, and as a result, the moduli spaces are no longer complex orbifolds, but rather real orbifolds with corners. These moduli spaces may be viewed as an explanation of the way that algebraic structures, such as A-infinity categories, cyclic homology, and the Cardy condition, enter topological field theory in two dimensions. This theory should also have applications to understanding the foundations of string theory.
The lectures will start by reviewing closed topological theories, before moving to more recent work in the open/closed theory on spaces with boundary.
From the work of Witten, the topology of the so-called Deligne-Mumford moduli spaces of Riemann surfaces with nodes plays a fundamental role in 2-dimensional topological gravity (known to mathematicians as Gromov-Witten theory). For example, by the work of Kontsevich and Manin, it is seen to underly the Witten-Dijkgraaf-Verlinde-Verlinde equation, and hence is intimately related to the theory of Frobenius manifolds and of integrable systems.
Most work on these moduli spaces has been focussed on the case of closed topological field theory. In these lectures, I will explore the moduli spaces, analogous to Deligne-Mumford moduli spaces, which play the corresponding role in the open theory. In this case, the world sheet (Riemann surface) has a boundary, and as a result, the moduli spaces are no longer complex orbifolds, but rather real orbifolds with corners. These moduli spaces may be viewed as an explanation of the way that algebraic structures, such as A-infinity categories, cyclic homology, and the Cardy condition, enter topological field theory in two dimensions. This theory should also have applications to understanding the foundations of string theory.
Posted by: IC
Wednesday, 24 Oct 2007
String vacua and algebraic geometry: an algorithmic approach
๐ London
Andre Lukas
(Oxford)
Backreacting Flavors in the KS Background: a New Cascade
Francesco Benini
(SISSA)
Abstract:
I present new analytic solutions of type IIB supergravity with fully backreacting D7-branes describing the addition of an arbitrary number of flavors to the Klebanov-Tseytlin and Klebanov-Strassler theories. I provide a detailed analysis of the field theory and of the duality cascade which describes its RG flow, Seiberg duality is understood as a large gauge transformation in supergravity. Moreover the string background suggests that the UV behavior is a duality wall.
I present new analytic solutions of type IIB supergravity with fully backreacting D7-branes describing the addition of an arbitrary number of flavors to the Klebanov-Tseytlin and Klebanov-Strassler theories. I provide a detailed analysis of the field theory and of the duality cascade which describes its RG flow, Seiberg duality is understood as a large gauge transformation in supergravity. Moreover the string background suggests that the UV behavior is a duality wall.
Posted by: IC
Thursday, 25 Oct 2007
Aspects of Gauge-Theory Orbit Space
Peter Orland
(New york)