Tentative Schedule
September 13
Speaker: Prof. Dmitri Kharzeev, Brookhaven National Laboratory
Title: "Mirror symmetry in super-dense matter"
Abstract:
I will discuss the fate of parity invariance (mirror symmetry) in hot
and dense quark-gluon matter. While parity is globally conserved in
Quantum ChromoDynamics,
the interplay of topology and external magnetic field can induce local
parity-odd effects. In particular, the local imbalance between left- and
right-handed fermions in the presence of magnetic field induces the
spatial separation of positive and negative electric charges ("the
Chiral Magnetic Effect").
In heavy ion collisions, this effect can be detected through the
separation of positive and negative hadrons with respect to the reaction
plane.
There is a recent evidence for charge separation from the experiments
at Relativistic Heavy Ion Collider. The effect has intriguing
implications for the cosmology of the Early Universe, and has analogs in
condensed matter physics (quantum wires and graphene), and in
astrophysics (particle acceleration in cosmic strings).
September 20
Speaker: Prof. Steven Kahn, Stanford University
Title: "The Large Synoptic Survey Telescope (LSST)"
Abstract:
The Large Synoptic Survey Telescope is a large-aperture, wide-field, ground-based telescope designed to survey over half of the sky in six optical colors every few nights. As such, it will enable a wide array of diverse scientific investigations, ranging from studies of small moving bodies in the solar system to constraints on the structure and evolution of the universe as a whole. A National Academy of Sciences panel charged with prioritizing future programs in astronomy and astrophysics recently ranked LSST has the highest priority large ground-based project for the next decade.
I will provide a brief overview of the design of LSST and then run through a "tour" of some of the most exciting science that is expected to come from this facility. Included will be topics in solar system science, stellar evolution, the structure of the Milky Way, galaxy formation, active galactic nuclei, the nature of the transient sky, and fundamental cosmology.
October 11
Speaker: Prof. Szabolcs Marka, Columbia University
Title: "Gravitational Waves, Neutrinos and Photons:Comprehensive MultiMessenger Astronomy in the Making"
Abstract:
Gravitational waves, ripples in the curvature of spacetime, carry
information about the nature of gravity and fascinating astronomical
phenomena never before observed by humanity, such as colliding black
holes or consumed neutron stars. The LIGO-GEO600-Virgo interferometric
gravitational-wave detector network has been successfully constructed
and operated at or exceeding its initial sensitivity target. Searches
for gravitational-wave signals at the sub-attometer level have already
provided meaningful constraints on the population and characteristics of
sources, in particular on the astrophysics of events which can also be
observed through other messengers, such as gamma-rays, X-rays, radio,
optical, and/or neutrinos. The simultaneous observation of neutrino or
electromagnetic emission could be a crucial aspect for the first direct
detections of gravitational waves, expected at the tens-of-zeptometers
sensitivity level within a few years. Information on the progenitor,
such as trigger time, direction and expected frequency range, can
enhance our ability to identify gravitational-wave signatures with
amplitudes close to the noise floor of the detector. Combining
gravitational waves with electromagnetic and neutrino observations
furthers the possibilities in extracting scientific insight that has
been hidden from us before. I will discuss and interpret the results and
successes from transient searches that have been completed with the
LIGO-GEO600-Virgo network. I will give insight on the ways the
multimessenger effort is currently being extended to include additional
astrophysical events and messengers. I will also describe the status,
some of the exciting science goals, and outlook for second and third
generation interferometric gravitational-wave detectors.
October 18
Speaker: Prof. Eduardo Ponton, Columbia University
Title: "Electroweak Symmetry Breaking: The Start of a New Era?"
Abstract:
The Standard Model of Particle Physics has been tested to exquisite
precision over the past three decades. Nevertheless, the nature of the
physics responsible for the breaking of the electroweak symmetry
remains unknown. This most basic issue is expected to be fully or
partially uncovered during the LHC era. It is also possible that "the
physics of the TeV scale" carries answers to other fundamental
questions, such as the origin of the observed flavor structure, the
identity of dark matter, or the origin of the baryon asymmetry of the
universe. Furthermore, theoretical research has determined that, in
spite of the impressive quantitative tests (at the quantum level) of the
basic standard model framework, there can be radical departures at the
TeV scale, such as the existence of additional spatial dimensions that
can be observable at the LHC. I will review how our present knowledge
has led us to suspect that the EW scale may provide important clues
regarding even smaller scales, and exemplify the possibilities for
physics beyond the standard model in the energy regime we are currently
exploring in collider experiments.
October 25
Speaker: Prof. Gustaaf Brooijmans, Columbia University
Title: "After the Standard Model"
Abstract:
From a particle physics point of view, the past thirty years can
rightfully be considered as the golden age of the standard model. Both
the theoretical and experimental knowledge of the structure of the
strong and electroweak interactions have reached impressive levels of
precision, and the agreement between experimental results and
theoretical predictions is stunning.
The standard model doesn't tell us anything about the nature of the
particles whose interactions it describes, however. We hope that data
taken at the LHC now and in the future will allow us to develop some
understanding of the origin of particle properties. According to some
models we will learn about particle masses through the discovery of the
Higgs boson, while others, for example, suggest that dynamics in
additional spatial dimensions might be the source of specific
properties. This colloquium will review some key aspects of our current
knowledge and how it was acquired, followed by a discussion of new
experimental approaches needed at the LHC.
December 6
Speaker: Prof. Richard Garwin, Thomas J. Watson Research Center, IBM Research Division
Title: "Science (and technology) to tame a wild deep-sea oil well"
Abstract:
In the Gulf of Mexico, the BP well Macondo-252, suffered a disaster in
April 2010 and spewed 5 million barrels of oil into the Gulf. It could
have been much worse. I describe the approaches to collecting the flow
and eventually to stopping it in the difficult environment of a deep
well that enters the seabed a mile below the sea surface, in the
hurricane-prone Gulf of Mexico.
December 13
Speaker: Prof. Brian Cole, Columbia University
Title: "First Direct Observations of Jet Quenching(?) by the ATLAS Experiment
in Lead-Lead Collisions at the LHC"
Abstract:
On November 6, 2010 the Large Hadron Collider (LHC) started colliding
lead nuclei at a nucleon-nucleon center of mass energy of 2.76 TeV.
Such collisions are expected to create strongly interacting matter at
temperatures in excess of 500 MeV ($> 1012$
degrees K) -- the highest temperatures ever created in the laboratory.
At such high temperatures, strongly interacting matter is predicted to
be in a novel state called a strongly interacting quark-gluon plasma
(sQGP), in which quarks and gluons normally "confined" within the
volume of a proton become "deconfined" over a much larger nuclear
volume. The ATLAS detector at the LHC was constructed primarily to
study high-energy proton-proton collisions. It turns out however to be
also an ideal instrument for studying sQGP properties in nuclear
collisions because its highly segmented calorimeters provide excellent
detection and measurement of "jets" of particles in very complex high
multiplicity environments. On November 26, 2010 ATLAS reported the
first observation of large imbalances in transverse momenta of pairs of
"jets" produced in the lead collisions. Unlike in proton-proton
collisions, pairs of back to back jets in nuclear collisions are found
to be highly momentum unbalanced in the plane transverse to the
incoming beams. The observation suggests that the hot sQGP created in
the lead-lead collision can change significantly the energy of one or
both jet partons before they fragment into jets of pions, kaons and
other particles. Such "quenching" of quarks and gluons was
theoretically predicted nearly two decades ago. Results from the
Relativistic Heavy Ion Collider have indirectly demonstrated jet
quenching through the suppressed yield of high-energy fragments of
jets. If the jet quenching interpretation is ultimately confirmed, the
recent ATLAS measurements would represent its first direct observation
via full calorimetric jet reconstruction.
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