January 26
Speaker: Prof. Steven S. Gubser, Princeton University
Title: "String theory: hot or cold?"
Abstract:
String theory may be able to help us understand the hot quark-gluon plasma formed in heavy ion collisions. It may also provide insights relevant to the low-temperature phenomena like superconductivity. Black holes in string theory provide a powerful venue for finite-temperature calculations. I will review some of the progress on applying such calculations to heavy-ion physics, including the rapid energy loss from heavy quarks. I will also describe some of the recent work relating string theory to low- temperature physics, including an explanation of how black holes can superconduct.
February 9
Speaker: Prof. Cumrun Vafa, Harvard University
Title: “Stringy Predictions for Particle Physics”
Abstract:
Recent progress in string theory has led to a vast landscape of consistent vacua for the theory. In this talk I will discuss how the principle of decoupling of quantum gravity from particle physics leads to a very narrow set of possibilities in this landscape. This rigid framework leads to specific predictions for particle physics, including a quantitative explanation of mass hierarchies for quarks and leptons. Moreover this approach to particle phenomenology leads to specific predictions for new physics at the LHC.
February 16
Speaker: Prof. Karsten Heeger, University of Wisconsin
Title:"Probing New Physics in Neutrino Experiments"
Abstract:
Neutrino mass and mixing are amongst the major discoveries of recent years. The discoveries at Super-Kamiokande, SNO, and KamLAND have provided unambiguous evidence for neutrino mass and demand that we make the first significant revision of the Standard Model in decades. Many important questions remain: Are neutrinos their own antiparticles? What is their mass scale? Can we use neutrinos to search for CP violation? Precision measurements of neutrino oscillation parameters and the search for neutrinoless double beta decay are now underway to determine the pattern of neutrino mixing and their masses. I will describe the latest results from KamLAND, discuss the prospects for understanding neutrino mass with the bolometric CUORE experiment, and outline future opportunities in neutrino oscillation physics.
February 23
Speaker: Prof. Stefan Schoenert, Max-Planck-Institut für Kernphysik
Title: "Cutting edge projects in low-energy particle and astroparticle physics"
Abstract:
Neutrinos are unique probes of particle physics, astrophysics and cosmology. As they do not carry electrical charge, neutrinos andanti-neutrinos could be identical, usually referred to as Majoranaparticles. An experimental proof of this fundamental feature would be a major break through and open the window to new physics beyond the Standard Model. A key aspect to decipher the underlying new physics isthe precise knowledge of the neutrino mixing angles. Neutrinos are aswell unique to probe the interior of the Earth, the sun or collapsingstars. The detection of high energy neutrinos will elucidate the acceleration mechanism of cosmic rays and give insights into the natureof the Dark Matter. After an introduction to this exciting researchfield, I will present results from the solar neutrino experiment Borexino, summarize the status of the reactor neutrino oscillation experiment Double Chooz, discuss the double beta decay experiment GERDAexperiment, and sketch future developments.
March 2
Speaker: Prof. Zoltan Fodor, University of Wuppertal
Title: "Cim: Hadron spectrum and the QCD transition"
Abstract:
More than 99% of the mass of the visible universe is made up of protons and neutrons. Both particles are much heavier than their quark and gluon constituents, and the Standard Model of particle physics should explain this difference. A full ab initio calculation of the masses of protons, neutrons, and other light hadrons, are presented using lattice quantum chromodynamics. The results completely agree with experimental observations. The generation of this hadronic mass is related to a transition in the early universe, which is also discussed.
March 9
Speaker: Prof. M. Zahid Hasan, Princeton University
Title: "Dirac Fermions, Topological Phases and Experimental discovery of Quantum Hall-like effects without Magnetic Field"
Abstract:
Most quantum states of condensed-matter are categorized by spontaneously broken symmetries (Landau paradigm). The remarkable discovery of charge quantum Hall effects (1980s) revealed that there exists an organizational principle of matter based not on the broken symmetry but only on the topological distinctions in the presence of time-reversal symmetry breaking. In the past few years, theoretical developments suggest that new classes of topological states of quantum matter might exist that are purely topological in nature in the sense that they do not break time-reversal symmetry hence can be realized without any applied magnetic field : "Quantum Hall-like effects without magnetic field". In this presentation, I report a series of experimental results documenting and demonstrating the existence of such a topologically ordered time-reversal-invariant state of matter and discuss the exotic electromagnetic (Wilczek’s theta vacuum) properties this novel phase of quantum matter mi ght exhibit and outline their potential use.
March 23
Speaker: Prof. David A. Weitz, Harvard University
Title: "Elasticity of Active Biopolymer Networks"
Abstract:
This talk will describe the mechanical properties of networks of biomolecules formed from proteins reconstituted from cells. Addition of active biomolecular motors to these networks can dramatically modify their properties, increasing their stiffness by several orders of magnitude. These networks represent a different class of materials, which are 'active,' having internal motors that convert chemical energy into mechanical energy. These networks can provide a route to synthesis of materials whose mechanics are controlled by enzymatic activity. They also offer insight into the mechanics of the cell, and suggest that motor activity may play an essential role in determining the stiffness of a cell.
March 30
Speaker: Dr. Caleb Scharf, Columbia University
Title: "The New Astrobiology"
Abstract:
The search for life beyond the confines of the Earth has had a checkered history and has often been confused and confusing. A number of remarkable discoveries and technical advances across scientific disciplines in the past twenty years have changed all this. I will review some of the key science that motivates this "new" astrobiology; from microbes that rely on natural radioactivity, to methane on Mars, complex molecules in interstellar space, and in particular the study of extrasolar planets. The accelerating pace of discovery on all fronts suggests that we may be getting close to the holy grail of astrobiology - to increase our sample size beyond unity.
April 6
Speaker: Prof. Viatcheslav Mukhanov, Ludwig-Maximilians University of Munich, Germany
Title: "Inflation after WMAP"
Abstract:
I will review the robust predictions of inflation and confront them with the most recent results on the cosmic microwave background fluctuations measurements.
April 27
Speaker: Dr. Marusa Bradac, University of California, Santa Barbara
Title: "Dark Matter in the "Bullet Cluster" 1E0657-56 and MACSJ0025-1222: Revealing the Invisible with 2 Cosmic Supercolliders"
Abstract:
The cluster of galaxies 1E0657-56 has been the subject of intense
research in the last few years. This system is remarkably well-suited
to addressing outstanding issues in both cosmology and fundamental
physics. It is one of the hottest and most luminous X-ray clusters
known, and is unique in being a major supersonic cluster merger
occurring nearly in the plane of the sky, earning it the nickname "the
Bullet Cluster". Recently we have discovered a new Bullet-like cluster,
MACSJ0025-1222. Allthough it does not contain a low-entropy,high density hydrodynamical `bullet,' this cluster exhibits many
similar properties to the Bullet Cluster, and so we also use it to
study dark matter.
In this talk I will present our measurements of the composition of both
systems (using gravitational lensing), show the (independent) evidence
for the existence of dark matter, and describe limits that can be
placed on the intrinsic properties of dark matter particles. In doing
so, I will explain how these clusters offer a serious challenge to
MOdified Newtonian Dynamics (MOND) theories. Finally I will conclude
with some preliminary results we have on using the Bullet cluster as a
`cosmic telescope' to explore the Universe in its infancy.
May 4
Speaker: Prof. Ali Yazdani, Princeton University
Title: "Visualizing Pair Formation on the Nanometer Scale and the Riddle of High-Temperature Superconductivity"
Abstract:
Electron pairing underlies the formation of a superconducting state.
The mechanism of pairing and the temperature at which pairs first form
in high-temperature copper-oxide superconductors have been debated for
the last twenty years. Do pairs form at the critical temperature like
conventional superconductors? What binds the electrons together? I
will describe how we experimentally visualize the process of pair
formation and probe what controls the strength of pairing in cuprates
on the atomic scale.
