- 2019-04-16 12:30 to 13:30Title: Companions and debris around white dwarfs
- Location:Danciger B building, Seminar room2019-04-16 12:00 to 13:30Speaker: Itsik Cohen, AARHUS University Abstract: In this talk I will present three different projects I have been working on.
- Location:Danciger B building, Seminar room2019-04-11 14:00 to 15:30Lecturer: Guy Bunin
The dynamics of some systems are directional, meaning that the state of a system can be characterized by a function that increases in time. This includes, for example, the growth of entropy in physical systems, or the growth of fitness in certain formulations of Darwinian evolution. Yet even when directionality holds, it might be sensitive to perturbations, such as external driving of physical systems, or interactions in evolutionary dynamics.
- 2019-04-11 12:00 to 13:00Highly entangled spin chains and exact tensor networks. I will describe new results on the high and low entangled ground states of deformed Moztkin and Fredkin and related models. I will present new exact tensor networks for these states, in the scale invariant limit and the highly entangled rainbow phase, which, remarkably, are the first examples of holographic tensor networks with finite bond dimension for ground states of gapless local Hamiltonians, and their relation to certain tiling problems.
- Location:Danciger B building, Seminar room2019-04-10 13:30 to 15:00Lecturer: Doron Grossman, Abstract: Self assembly of molecules into supramolecular structures is an important process through which non trivial structures are formed in nano-metric scale. The resulting structure depends on chemical and physical principles that govern the process, and may be sensitive to the exact conditions in which they are formed. Typically, such self assembled structures are residually stressed, due to mismatch of the constituent element. Identifying the principles and ways in which different structures are formed, affects signicantly the ability to control,
- 2019-04-09 12:30 to 13:30
- Location:Levin building, Lecture Hall No. 82019-04-08 12:00 to 13:30Lecturer: Leo Radzihovsky from the University of Colorado at Boulder Abstract: I will take the audience on a bit of a rollercoaster ride, pedagogically discussing a recently discovered exotic liquid crystal state, the heliconical nematic, that emerges as a result of a spontaneous chiral symmetry breaking, a holy grail dating back to Louis Pasteur. I will also explain how low-energy physics of this and related states of matter can be understood as an emergent Higgs mechanism, with critical fluctuations extending throughout the low temperature phase.
- 2019-04-07 12:30 to 13:30
- 2019-04-04 12:00 to 13:00Title: “Hot” electron generation in plasmonic nanostructures – forget what you have been told… Abstract: We present a self-consistent theory of the steady-state electron distribution in metals under continuous-wave illumination which treats, for the first time, both thermal and non-thermal effects on the same footing. We show the number of non-thermal electrons (i.e., the deviation from thermal equilibrium) is very effect, so that the power that ends up generating these non-thermal electrons is many orders of magnitude smaller than the amount of power that leads to regular heating.
- Location:Danciger B building, Seminar room2019-04-03 12:00 to 13:30Speaker: Guy Gur Ari from google Abstract: The large width limit has emerged as a useful tool for studying deep neural networks. We adapt the 't Hooft expansion to this case, allowing us to easily work out scaling laws in large width networks using Feynman diagrams. We apply these techniques to quantities involving deep network observables such as the loss function, the Hessian, and the Neural Tangent Kernel.