Integrated Calendar

Gene activity (expression) determines the response of a living cell to environmental signals and supports the stabilization of a well-determined cell state in the face of intrinsic and environmental perturbations. How the intracellular complex molecular dynamics self-organizes into stable cell states is one of the most fascinating open questions in biophysics. After presenting the general problem of the emergence of stable cell states, I'll discuss our experimental approach allowing measurements of the long-term intracellular processes in dynamic cell populations, gaining insight into the genes' collective many-body dynamics. We show that two cell populations derived from a single steady-state mother population, fed by the same medium and exhibiting an invariant growth phenotype in response to an environmental challenge, displayed diverse gene activity patterns for genes essential for their metabolism. These degenerate gene expression patterns emerged from population-collective dynamics. This surprising result suggests that in a wide range of biological contexts, gene expression reflects a self-organization process coupled to collective population-environment dynamics.

In this talk, largely based on http://arxiv.org/abs/1011.2218
I will offer a new interpretation of the Verlinde formula for a group G in terms of D-branes on the moduli space of Higgs bundles for the Langlands dual group. Hyperholomorphic sheaves and (B,B,B) branes play an important role in this approach to the Verlinde formula.

In this talk I will review recent progress on understanding the N=2 3d SCFT describing the low energy
dynamics of M2-branes on generic toric CY cones. A crucial role is played by 3d monopole operators, which encode the detail of a particular M-theory reduction to type IIA string theory.