Friday 27 September 2024 |
Events for day: Wednesday 16 October 2019 |
13:30 - 15:00 Weekly Seminar Mimetic Gravity: Pros and Cons School ASTRONOMY In this talk, we first review the idea of mimetic gravity and show how dark matter naturally arises in this scenario in the cosmological background. We show that the setup is unstable at the level of perturbations and we will introduce some possible healthy extensions of this scenario. Replacing the scalar field with a general p-form, in the second part, we find a new mimetic theory and we particularly focus on the case of one-form gauge potential. This model is free of instabilities and provides an energy density which behaves like the spatial curvature in the cosmological background. ... 14:00 - 15:00 Weekly Seminar Condensed Matter and Statistical Physics Group Mechanical Behavior of Smart Composite Structures: From Nano- to Macro- Scale School PHYSICS Seminar Room (classroom A), Farmanieh Building, IPM ... 14:00 - 15:00 Weekly Seminar Combinatorics and Computing An overview of distributed algorithms and a distributed constant approximation factor algorithm for finding minimum dominating set of planar graphs School MATHEMATICS An overview of distributed algorithms and a distributed constant approximation factor algorithm for finding minimum dominating set of planar graphs ... 14:00 - 15:00 Weekly Seminar Mechanical Behavior of Smart Composite Structures: From Nano- to Macro-Scale School NANO SCIENCES Mechanical Behavior of Smart Composite Structures: From Nano- to Macro-Scale Abstract: One of the challenges of researchers in the recent years is to find innovative concepts to bring superior properties of smart composite materials from the nano-level to macro-level. In this lecture a summary of updated knowledge on mechanical behavior of smart composite structures will be presented. This talk pay particular attention to the different length-scales (macro, micro and nano) as related to obtaining a deeper understanding of the vibration, bending, buckling and impact behavior of advanced materials. The presen ... 15:00 - 16:00 Weekly Seminar 2d flat space holography and warped-Schwarzian theory School PARTICLES AND ACCELERATORS Abstract:The Sachdev-Ye-Kitaev (SYK) model is an interacting statistical quantum mechanical model. In low temperature, this model has a (1+1)-dimensional dilaton-gravity description in AdS_2 spacetime. The key link between gravity and field theory side is the boundary effective action denoted as "Schwarzian theory". In this talk after reviewing this construction, we set up this correspondence in the case of (1+1)-dimensional dilaton-gravity in flat spacetime and derive the analogous boundary action which coincides with the one discovered recently in1908.08089 as "warped Schwarzian theory". The talk is base on ... 15:30 - 16:30 Geometry and Topology Weekly Seminar Conformally Invariant Observables in the Double-dimer Model School MATHEMATICS We are going to talk about a two-dimensional model in statistical mechanics, the double-dimer model, which is simply a straightforward generalization of the dimer model. The latter is well-known in both physics and mathematics because of its particular features and substantial relations to many contexts, known in combinatorics as a perfect-matching problem. Here the emphasis is on the critical behavior of the loop ensembles of the double-dimer model, conjectured to converge to the level sets of the Gaussian free field and Schramm-Loewnerevolution or conformal loop ensembles with parameter 4. We use the Grassmannian representation of the dimer ... |