## Events - Daily

Monday,
November 30 |
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Biophysics Seminar - Oskar Hallatschek, Berkeley "The role of chance in the survival of the fittest” Joseph Henry Room · 12:00 p.m.– 1:00 p.m. |

CM Seminar, Avraham Klein, Hebrew University of Jerusalem, "Vortex core deformation in weakly coupled superfluids" Quantum vortices in weakly coupled superfluids have a large healing length, so that many particles reside within the vortex core. They are characterized by topologically protected singular points, which in principal should keep their core structure rigid. I will describe how, in practice, the point singularity of a vortex deforms into a line singularity, in proportion with the Magnus force experienced by the vortex. The vortex structure is described by weak solutions of the Gross-Pitaevskii equation, similar to shock waves in hydrodynamics. I will discuss how the core deformation significantly affects many aspects of vortex dynamics. PCTS Seminar Room · 1:15 p.m.– 2:30 p.m. |

High Energy Theory IAS - Maurizio Pierini, CERN, “Signs of Hope: A Few LHC Run I Results to Watch for Run II” During the first LHC long shutdown, the CMS collaboration finalised the study of the 8TeV data collected in 2012. Within the impressive amount of results produced, a few searches for new physics show a tension with the prediction from the Standard Model. While the significance is still too small to allow any conclusion, some of these excesses could reveal the first footprint of new processes at the TeV scale. I will discuss a few of these excesses, and give a perspective of the expectation for Run II. Bloomberg Lecture Hall - Institute for Advanced Study · 2:30 p.m.– 3:30 p.m. |

Special Pheno & Vino, Clifford Cheung, Caltech, "The Periodic Table of Effective Field Theories" The modern S-matrix program has seen immense progress constructing scattering amplitudes in gauge and gravity theories without the aid of a Lagrangian, instead using only physical principles like Lorentz invariance and factorization. In this talk, I discuss how a similar approach is sufficient to construct effective field theories (EFTs), yielding a ``periodic table'' of scalar EFTs labelled by two numbers. We derive these EFTs--Lagrangians, symmetries, and all--from an ansatz of all possible S-matrices consistent with Lorentz invariance, factorization, and a certain infrared property, obtaining well-known examples like the chiral Lagrangian, Dirac-Born-Infeld theory, and the Galileon. We the show how tree amplitudes in these EFTs are constructible via on-shell recursion relations. With these methods one can prove stringent no-go theorems on the space of EFTs and, in principle, even discover new ones. Jadwin 303 · 4:00 p.m.– 5:30 p.m. |