Thu, 13 Nov 2014
14:00
L4

The topology of rationally and polynomially convex domains

Kai Cieliebak
(Augsburg)
Abstract

Rationally and polynomially convex domains in ${\mathbb C}^n$ are fundamental objects of study in the theory of functions of several complex variables. After defining and illustrating these notions, I will explain joint work with Y.Eliashberg giving a complete characterization of the possible topologies of such domains in complex dimension at least three. The proofs are based on recent progress in symplectic topology, most notably the h-principles for loose Legendrian knots and Lagrangian caps.

Tue, 04 Nov 2014
15:45
L4

Cobordisms between tangles

Akram Alishahi
(Bonn)
Abstract

 In a previous work, we introduced a refinement of Juhasz’s sutured Floer homology, and constructed a minus theory for sutured manifolds, called sutured Floer chain complex. In this talk, we introduce a new description of sutured manifolds as “tangles” and describe a notion of cobordism between them. Using this construction, we define a cobordism map between the corresponding sutured Floer chain complexes. We also discuss some possible applications. This is a joint work with Eaman Eftekhary.

Tue, 28 Oct 2014

15:45 - 16:45
L4

Infinitely many monotone Lagrangian Tori in CP^2

Renato Vianna
(Cambridge)
Abstract
In previous work, we constructed an exotic monotone Lagrangian torus in $\mathbb{CP}^2$ (not Hamiltonian isotopic to the known Clifford and Chekanov tori) using techniques motivated by mirror symmetry. We named it $T(1,4,25)$ because, when following a degeneration of $\mathbb{CP}^2$ to the weighted projective space $\mathbb{CP}(1,4,25)$, it degenerates to the central fibre of the moment map for the standard torus action on $\mathbb{CP}(1,4,25)$. Related to each degeneration from $\mathbb{CP}^2$ to $\mathbb{CP}(a^2,b^2,c^2)$, for $(a,b,c)$ a Markov triple -- $a^2 + b^2 + c^2 = 3abc$ -- there is a monotone Lagrangian torus, which we call $T(a^2,b^2,c^2)$.  We employ techniques from symplectic field theory to prove that no two of them are Hamiltonian isotopic to each other.
Tue, 11 Nov 2014

12:00 - 13:00
L5

SYM amplitudes from BRST symmetry

Oliver Schlotterer
(AEI Golm)
Abstract
This talk describes a method to compute supersymmetric tree amplitudes and loop integrands in ten-dimensional super Yang-Mills theory. It relies on the constructive interplay between their cubic graph organization and BRST invariance of the underlying pure spinor superspace description. After a general introduction to this kind of superspace, we discuss a canonical set of multiparticle building blocks which represent tree level subdiagrams and are guided by their BRST transformation. These building blocks are shown to yield a compact solution for tree level amplitudes, and the applicability of the BRST approach to loop integrands is exemplified through recent examples at one-loop.
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