IPM Calendar 
Wednesday 16 October 2019   Today  
Events for day: Wednesday 16 October 2019    
           13:30 - 15:00     Weekly Seminar
Mimetic Gravity: Pros and Cons


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


Seminar Room (classroom A), Farmanieh Building, IPM ...

           14:00 - 15:00     Weekly Seminar
Mechanical Behavior of Smart Composite Structures: From Nano- to Macro-Scale


Mechanical Behavior of Smart Composite Structures: From Nano- to Macro-Scale


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


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


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 ...