# Events Archive

## Events Archive

### Biophysics Seminar Series - Fred Wolf (Max Planck Institute for Dynamics and Self-Organization)

Mon, Nov 19, 2012, 12:00 pm to 1:00 pm

"Dynamical entropy production in recurrent neuronal circuits"

### High Energy Theory Seminar - Alfred Shapere - University of Kentucky - "Time Crystals"

Fri, Nov 16, 2012, 1:30 pm to 2:30 pm

I consider a class of simple classical dynamical systems which exhibit motion in their lowest-energy states. Their Lagrangians have wrong-sign kinetic terms and their Hamiltonians are multivalued functions of momentum, yet they are amenable to quantization. Their field theoretical generalizations may have applications in condensed matter physics...

### Math Phys Seminar: Sylvia Serfaty (Université Pierre et Marie Curie - Paris 6 and Courant Institute) 'Towards crystallization in Coulomb systems'

Tue, Nov 13, 2012, 3:30 pm to 5:00 pm

We are interested in the statistical mechanics of (classical) two-dimensional Coulomb gases and one-dimensional log gases in a confining potential.

### Condensed Matter Seminar - Nuh Gedik, Massachusetts Institute of Technology, " Ultrafast Probing of Dirac Fermions in Topological Insulators"

Mon, Nov 12, 2012, 1:15 pm to 2:30 pm

The three-dimensional topological insulator (TI) is a new quantum phase of matter that exhibits quantum-Hall-like properties, even in the absence of an external magnetic field. Charge carriers on the surface of a TI behave like a two-dimensional gas of massless helical Dirac fermions for which the spin is ideally locked perpendicular to the...

### Biophysics Seminar Series - Jeremy England, MIT

### High Energy Theory Seminar - IAS - Michele Del Zotto, SISSA - “Evidences for D(G,s) Theories”

Fri, Nov 9, 2012, 1:30 pm to 2:30 pm

In the past three years some aspects of the duality in between representation theory of associative algebras and N=2 supersymmetric theories in four dimensions have proven to be crucial for understanding the so-called BPS-quiver theories.

### PCTS Series Nonequilibrium Physics Strongly Interacting Matter & Light, Michel Devoret Yale Univ. Parametric Amplification of Quantum Signals

Fri, Nov 9, 2012, 11:00 am to 12:30 pm

Quantum Mechanics puts a limit on how small the degradation of information passing through an amplifier can be. It is known theoretically that the minimum noise added by an amplifier to the signal amounts, in phase preserving mode, to at least half a photon at the signal frequency.

### Physics Colloquium - Michel Devoret, Yale University - “The Road to the Poles: Quantum Measurements that Steer rather than Collapse"

Thu, Nov 8, 2012, 4:30 pm to 5:30 pm

A quantum system subject to the infinitely-strong measurement of textbook physics undergoes a discontinuous, random state collapse. All phase information in a superposition of the eigenstates of the measurement apparatus is then suddenly erased from the system under observation.

### High Energy Theory Informal Seminar - IAS - Yang Zhang, Niels Bohr Institute - “Integrand-Level Reduction of High-Loop Scattering Amplitudes via Co

Wed, Nov 7, 2012, 1:30 pm to 2:30 pm

Integrand-level reduction is a powerful method for loop scattering amplitudes computation. We present an algebraic geometry approach for Integrand-level reduction, which is valid for any renormalizable theories and arbitrary loop orders, in principle.

### HET Seminar - Koenraad Schalm, University Leiden, NL - Strongly coupled electron systems from holography and the Birth and Collapse of anti-de-Sitter

Mon, Nov 5, 2012, 2:45 pm to 3:45 pm

The application of the holographic AdS/CFT correspondence to condensed matter systems has shown us remarkable new insights into strongly coupled quantum matter.

### PCTS Series Nonequilibrium Physics Strongly Interacting Matter & Light Jonathan Keeling St. Andrews Univ UK, Non-equilibrium coherence in light-matter

### Biophysics Seminar Series - Marcelo Magnasco, Rockefeller

### High Energy Theory Seminar - IAS - David Simmons-Duffin, IAS - “Projectors, Shadows, and Conformal Blocks”

Fri, Nov 2, 2012, 1:30 pm to 2:30 pm

We introduce a method for computing conformal blocks of operators in arbitrary Lorentz representations in any spacetime dimension, making it possible to apply bootstrap techniques to operators with spin. The key idea is to implement the "shadow formalism" of Ferrara, Gatto, Grillo, and Parisi in a setting where conformal invariance is manifest.

### High Energy Theory Informal Seminar- IAS-Joe Polchinski, KITP, University of CA, Santa Barbara-Scale & Conformal Invariance in Quantum Field Theory

Tue, Oct 30, 2012, 1:30 pm to 2:30 pm

### High Energy Theory Seminar - IAS - Joe Polchinski, KITP, University of California, Santa Barbara - “Black Holes: Complementarity or Firewalls?”

Mon, Oct 29, 2012, 2:30 pm to 3:30 pm

I argue that the following three widely believed statements cannot all be true: (i) Hawking radiation is in a pure state, (ii) the information carried by the radiation is emitted from the region near the horizon, with low energy effective field theory valid beyond some microscopic distance from the horizon, and (iii) the infalling observer...

### Physics Colloquium - Ashvin Vishwanath, University of California, Berkeley - "Information, Entanglement and the Quantum Phases of Matter"

Thu, Oct 25, 2012, 4:30 pm to 5:30 pm

Many states of matter, including ferromagnets and superfluids, are ultimately described by a classical order parameter despite being composed of quantum particles. However, recent experiments have impelled us to look for new forms of emergence that are intrinsically quantum mechanical.

### Condensed Matter Seminar - Kobi Kraus, Weizmann Institute of Science Topological States and Adiabatic Pumping in Quasicrystals

Tue, Oct 23, 2012, 1:15 pm to 2:30 pm

Abstract: The discovery of topological insulators has sparked considerable interest in the study of topological phases of matter. Yet, realizations of these phases of matter are scarce. In this talk we will show, both theoretically and experimentally, that quasicrystals possess high-dimensional topological phases.

### High Energy Theory Seminar - Rak-Kyeong Seong - Imperial College London - "An evolution of Brane Tilings"

Mon, Oct 22, 2012, 2:30 pm to 3:30 pm

One way in which supersymmetric gauge theories can arise in string theory is as worldvolume theories of probe branes at toric Calabi-Yau singularities. For N=1 4d worldvolume theories of D3 branes at Calabi-Yau 3-fold singularities, the field theory information can be represented by a bipartite graph on a torus, which is known as a brane tiling.

### Condensed Matter Seminar - Prof Xiao-Liang Qi, Stanford University - "Synthetic non-Abelian anyons in fractional Chern insulators and beyond"

Mon, Oct 22, 2012, 1:15 pm to 2:30 pm

An exciting new prospect in condensed matter physics is the possibility of realizing fractional quantum Hall states in simple lattice models without a large external magnetic field, which are called fractional Chern insulators. A fundamental question is whether qualitatively new states can be realized on the lattice as compared with ordinary...

### High Energy Theory Seminar - IAS - Gil Paz, Wayne State University - “The Charge Radius of the Proton, A Five Sigma Discrepancy?”

Fri, Oct 19, 2012, 1:30 pm to 2:30 pm