Events - Weekly
April 2013 >>
|Sunday, April 21|
|Monday, April 22|
Ben de Bivort (Harvard) "The Neurobiology of Individuality"
Joseph Henry Room · 12:00 p.m.– 1:00 p.m.
Condensed Matter Seminar, Oleg Tchernyshyov, Z_2 spin liquid in the Heisenberg antiferromagnet on kagome
A spin liquid is a hypothetical quantum ground state of a frustrated Heisenberg magnet conjectured by P.W. Anderson in the 1970s. Its distinguishing features are (1) a lack of magnetic order and (2) a degeneracy that depends on the topology of the system. The status of spin liquids has been recently upgraded from purely speculative to plausible as these ground states were found in relatively simple two-dimensional spin models on square and kagome lattices. Experiments with herbertsmithite yielded clues of spin excitations with fractional spin 1/2 in a kagome antiferromagnet.
I will present a phenomenological Z_2 lattice gauge theory that describes low-energy properties of the spin liquid in a S=1/2 Heisenberg antiferromagnet on kagome. It reproduces many of the characteristic features observed in recent numerical studies of the model, including the ground-state degeneracy, response to quenched disorder, and spinon states near the system's edge.
PCTS Seminar Room · 1:15 p.m.– 2:30 p.m.
High Energy Theory Seminar - IAS - Gerald Gabrielse, Harvard University - ACME: Obtaining an Electron Electric Dipole Moment from ThO
The electron edm is an important constraint on extensions to the Standard Model such as supersymmetric models. ACME is closing in on a more sensitive measurement of this moment, profiting from the huge electric field within the ThO molecule.
Bloomberg Lecture Hall - Institute for Advanced Study · 2:30 p.m.– 3:30 p.m.
|Tuesday, April 23|
Informal HET Seminar - IAS-Ken Intriligator, U. of California, San Diego - Aspects of Three Dimensional N=2 Chern Simons Matter Field Theories
Bloomberg Lecture Hall - Institute for Advanced Study · 1:30 p.m.– 3:00 p.m.
|Wednesday, April 24|
Special PCTS Seminar - Horacio Casini, Centro Atomico Bariloche - Physical entanglement entropy: relative entropy and mutual information
I will describe general facts about entanglement entropy in QFT and discuss two different ways to get rid of the regularization ambiguities, using mutual information and relative entropy. Then i will show relative entropy gives a proof of a well defined version of the Bekenstein bound, an offer a strong test to holographic entropy. It can also be used to do "vacuum state tomography" from the entropy functional. In a second part of my talk I will show mutual information can be used to give a precise unambiguos definition of the central charge in the c-theorem for d=3, which in principle can be computed using any regularization. I will revise the proof of the c-theorem in terms of mutual information.
PCTS Seminar Room · 2:30 p.m.– 4:00 p.m.
|Thursday, April 25|
Hamilton Lecture - Joe Incandela, University of California-Santa Barbara and CERN, "The Search for the Higgs Boson: Discovery at the LHC"
The Large Hadron Collider (LHC) at CERN near Geneva Switzerland has performed spectacularly well in its first major running period from December 2009 through February 2013. Data of unprecedented quality and quantity have been recorded for proton-proton collisions at energies of 7 and 8 Trillion electron Volts – the highest energies ever obtained by man. In this lecture, Joe Incandela will give an overview of the decades-long, worldwide effort to construct and operate the LHC accelerator and the ATLAS and CMS experiments that together represent the largest, most complex systems ever built for physics research. The scientific goals of the LHC program will be reviewed with emphasis on the Higgs boson whose role in defining the structure and evolution of our universe is profound, and whose unusual properties may have extraordinary implications. Highlights from the discovery announced July 4th and more recent studies with much more data will be shown, followed by a brief look at preparations, expectations and hopes for future results in years to come.
McDonnell A02 · 8:00 p.m.–10:00 p.m.
|Friday, April 26|
|Saturday, April 27|