DATE
Thursday
March 7, 2013
3:004:00 P.M.
ILB Room 250
INVITATION
SLIDES
Thursday
November 1, 2012
3:00 PM
ILB Room 250
SPEAKER
The year 2012 may be forever remembered in physics as the year in which the longhunted Higgs boson was finally cornered. It was also one more year in which supersymmetry, the longsought guardian of the Higgs, was not found.
Has supersymmetry simply eluded us? Is it waiting for the next, higher energy phase of the LHC program? I will examine the coupled motivations for the
Higgs boson and for supersymmetry, and consider whether the current data is pointing to weakscale supersymmetry, or can be used to rule the theory out entirely.
References:
K. Dienes and C. Kolda, Twenty Open Questions and a Postscript:
Supersymmetry enters the era of the LHC. Published in Perspectives on
Supersymmetry II, ed. G. Kane, 2010.
Although metals are shiny materials that highly reflect visible light, it is well known that light transmission through metals increases beyond the plasma frequency. Nanoplasmonics is a relatively new field of technology that studies surface plasmons, the collective oscillations of free electrons on the interface between metal clusters and a dielectric. When the metal clusters interact with light, the surface plasmon resonance can be observed. This surface plasmon resonance can improve light absorption, charge separation or charge collection in devices and finds its application in biomedical engineering, optoelectronic devices, waveguides, and Raman spectroscopy. In this colloquium we will focus how surface plasmons can improve efficiency in polymer bulk heterojunction photodetecting and photovoltaic devices
INVITATION
SLIDES
PUBLIC LECTURE
Thursday
September 27, 2012
7:308:30 p.m.
ILB 140
INVITATION
Thursday
September 27, 2012
3:004:00 p.m.
ILB 250
INVITATION
References:
D. A. Genov, A. K. Sarychev, and V. M. Shalaev, Surface plasmon excitation and correlationinduced localizationdelocalization transition in semicontinuous metal films, Phys. Rev. B 72, pp. 11310214, 2005.
H. A. Atwater and A. Polman, "Plasmonics for improved photovoltaic device," Nature Materials, vol. 9, pp.205213, 2010.
Humans have undoubtedly asked "Are We Alone?" for millennia, but ours is the generation in which we take the first step towards an answer by asking "Do
Habitable Planets Exist?" I will begin with our primitive definition of habitable, using the case studies from our solar system: Venus, Earth, Mars and Jupiter's icy moon Europa. What planetary properties ultimately control a planet's habitability? Then I will describe the search for extrasolar planets, both methods and results. I will concentrate on the Kepler mission which is closing in on its ambitious goal of "Earthsized planets on Earthlike orbits around Sunlike stars". With an average discovery rate of several planets per day, it may just be a matter of time before Kepler finds one. What then??
References: http://iopscience.iop.org/0004637X/736/1/19/
http://www.nature.com/nature/journal/v412/n6843/full/412237a0.html
NASA's Curiosity rover became a household name when it landed in August, but it's only one of an impressive suite of missions to reveal the secrets of Mars' surface, atmosphere and deep interior. The talk will begin with a review of the latest news from Curiosity, and its role in the search for evidence of a warmer, wetter climate in the past. Then I will describe the upcoming MAVEN mission, launching in 2014. MAVEN is an orbiter designed to study the upper atmosphere and test the hypothesis that most of Mars' atmosphere was lost to space. I will emphasize the role of the Imaging UV Spectrograph, undergoing final tests now at the Laboratory for Atmospheric & Space Physics. One of the instrument's key capabilities is the challenging measurement of the deuter1iumtohydrogen ratio, an critical test of atmospheric escape. I will follow with a brief preview of NASA's justannounced INSIGHT mission, carrying a seismometer and drill to probe Mars' interior. I will end with a short discussion of the longterm possibilities of a Mars Sample Return mission and human exploration of Mars.
Reference:
Thursday
March 29, 2012
3:30 4:30 P.M.
ILB Room 250
INVITATION
SLIDES
Thursday
February 16, 2012
3:304:30 P.M.
ILB 250
INVITATION
SLIDES http://www.nature.com/nature/journal/v412/n6843/full/412237a0.html
About 10 microseconds after the big bang, the universe was too hot and dense for quarks to bind to form protons, neutrons and other hadrons. Instead, it may have existed in a state called the quarkgluon plasma, in which quarks and the gluons that carry the strong force roamed unconfined. Scientists may have recently produced this state in the laboratory using large particle accelerators to collide heavy ions at enormous energies, producing matter a billion times hotter than the sun. I will discuss experimental approaches to the production, detection, and characterization of this novel state of matter as well as the latest results from the Relativistic Heavy Ion Collider at Brookhaven National
Laboratory and the Large Hadron Collider at CERN.
References:
Dependence on pseudorapidity and on centrality of charged hadron production in PbPb collisions at sqrt(s_NN) = 2.76 TeV/CMS
Collaboration J. High Energy Phys. 08 (2011) 141
Quantum Chromodynamics (QCD) is the theory that describes how quarks and gluons bind to form protons, neutrons, mesons, and their partner particles. But after decades of effort, we still do not know exactly *how* this happens. In particular, we have a theory, but have not been able to use that theory to make reliable predictions about excited bound states, although various models and numerical simulations exist. Recently, new and totally unexpected particles were found at socalled Bfactories, and confirmed at other facilities. These new particles appear to be bound states of QCD of a type that have never been seen before. We hope that by analyzing their behavior we can obtain clues about how they are formed. I will discuss the properties of these new particles and what insights they provide about QCD.
References:
N. Brambilla, et al. "Heavy quarkonium: progress, puzzles, and opportunities," Eur.Phys.J. C71 (2011) 1534, arXiv: 10105827 (hepph), section 2.3.
Thursday
October 13, 2011
3:30 4:30 PM
ILB Room 250
INVITATION
SLIDES
Thursday
September 29, 2011
3:30 4:30 PM
ILB Room 250
INVITATION
SLIDES
Thursday
September 15, 2011
3:30 4:30 P.M.
In this talk I will briefly review the nature and scope of various types of information being acquired at the molecular level from cells and mention various challenges we face in integrating this type of data into the creation of mathematical models of various biophysical processes. One of the simplest biophysical systems which displays interesting dynamics is the circadian
(~24hr) clock from cyanobacteria. It is the first and only known molecular circadian clock which functions outside a cell (in a test tube) and consists of just three distinct proteins. I will give an experimental theoretical overview of this in vitro clock and describe recent attempts to extend the in vitro models to include transcription and translation processes in cells. Recent direct numerical simulations of the clock using a stochastic matrix model with rates constrained by experiment indicate specific molecular mechanisms necessary for maintaining synchrony; similar mechanisms may also be operative in clocks from higher organisms or more generally in other intracellular processes where population synchronization is needed for temporal precision.
References:
Nakajima M, Imai K, Ito H, Nishiwaki T, Murayama Y, et al. (2005)
Reconstitution of circadian oscillation of cyanobacterial KaiC phosphorylation in vitro. Science 308: 414415.
The phenomena of superconductivity and thermoelectrics are extremely attractive for green energy applications, because they are environmentally benign. However, adequate materials with high efficiency and low cost are yet to be discovered. In my talk, I will discuss the advances and challenges in these two fields.
References:
F. Hunte et al "Twoband superconductivity in LaFeAsO(0.89)F(0.11) at very high magnetic fields" Nature Letters Vol 453| 12 June 2008
ILB Room 250
INVITATION
SLIDES
Thursday
April 21, 2011
4:00 PM
ILB Room 250
INVITATION
SLIDES
PUBLIC LECTURE
Thursday
April 14, 2011
7:308:30 P.M.
Organic molecules such as tetracene crystallize into solids that can be semiconductors, metals, or even superconductors. Although they were rst developed over half a century ago, it is only fairly recently that the considerable promise that organic semiconductors hold as materials for electronics, display technologies, and solar cells has begun to be realized.
Lightweight, exible, and inexpensive, these materials oer an attractive balance between cost and performance, complemented by versatility and functionality accomplished by means of molecular design. I will review the physics of organic semiconductors and describe how their electronic and optical properties can be utilized in a variety of applications.
References:
H. Klauk,"Organic thinfilm transistors,"Chemical Society Reviews 39,
26432666 (2010). DOI: 10.1039/b909902f
Statistical physics forms the traditional foundation for thermodynamics, illustrating how concepts such as entropy and temperature emerge from the statistics of many interacting molecules. This framework has been immensely successful for systems in thermal equilibrium. Yet, many of the most interesting phenomena in nature take place very far from equilibrium including, for example, living organisms or the earth's ecosystem. In this talk, I will try to give a flavor of the breadth of nonequilibrium phenomena and how to apply lessons learned in physics to much broader, interdisciplinary questions such as the modeling of biological systems, stock indices and traffic jams.
References:
Statistical Mechanics of Driven Diffusive Systems. B. Schmittmann and
R.K.P. Zia, Vol 17 of Phase Transitions and Critical Phenomena, eds. C.
Domb and J.L. Lebowitz (Academic Press, N.Y. 1995), 220 pp.
Towards a model for protein production rates. J.J. Dong, B.
Schmittmann, and R.K.P. Zia, Journal of Statistical Physics 128, 2134
(2007), Special Issue on Biocomplexity VIII: Applications of Methods of
Stochastic Systems and Statistical Physics in Biology; q bio.BM/0602024.
Lack of consensus in social systems. I. J. Benczik, S. Z. Benczik, B.
Schmittmann, and R.K.P. Zia, Europhysics Letters 82, 48006: 15
(2008); arXiv:0709.4042
Life Sciences Lecture Hall 3
INVITATION
SLIDES
This lecture will explore the development of our knowledge and understanding of the extent of Universein both space and in time. Beginning 100 years ago with the view that the universe contained a single galaxy, a few million visible stars and 9 planets, we will move on to Hubble's discovery of billions of other galaxies and the expansion of the Universe and to current understanding of a
Universe comprised of dark matter and dark energy with billions of planets
(now only 8 in our solar system!). The lecture will end with speculations about the multiverse and its philosophical implications.
References:
Frieman, Turner, and Huterer, Annual Reviews of Astronomy and
Astrophysics 46, 385 (2008) [arXiv: arXiv:0803.0982]
Thursday
April 14, 2011
3:00 PM
ILB Room 250
INVITATION
SLIDES
Thursday
March 24, 2011
4:00 PM
ILB Room 250
INVITATION
SLIDES
A little over ten years ago two groups studying distant supernovae discovered that the expansion of the Universe is speeding up and not slowing down, and in
December 1998 Science Magazine picked Cosmic Acceleration as the Scientific
Breakthrough of the year. This remarkable discovery provided the final, missing piece in today's consensus cosmological model as well as posing the most profound mystery in all of science. Two possible explanations for cosmic acceleration are the repulsive gravity of a mysterious and very elastic new form of energy (``dark energy'') or new gravitational physics. Ten years after the discovery, the evidence for cosmic acceleration has gotten stronger and the mystery has deepened. In this talk I will review the present status of the mystery of cosmic acceleration.
References:
Frieman, Turner, and Huterer, Annual Reviews of Astronomy and
Astrophysics 46, 385 (2008) [arXiv: arXiv:0803.0982]
A brief overview of the basic phenomena and principles of image acquisition and reconstruction will be presented. We will also present examples of functional Brain Imaging, Magnetic Resonance Angiography (MRA), and
Gadolinium Contrast Imaging.
References:
The Essential Physics of Medical Imaging. Bushberg et al.
Magnetic Resonance Imaging. S. C. Bushong.
Thursday
October 28, 2010
4:00 5:00 P.M.
ILB Room 250
INVITATION
SLIDES
Friday
October 8, 2010
3:45 4:45 P.M.
ILB Room 250
INVITATION
SLIDES
PUBLIC LECTURE
The Bfactories have successfully exploited the unique advantages of the
Upsilon(4S) resonance to study many aspects of the Bd and Bu mesons. The
Upsilon(10860) resonance, also known as Upsilon(5S), which is above mass threshold for the Bs and shares many of the same advantages, has been relatively unexplored. The Belle experiment has collected 120 fb1 at the
Upsilon(10860) and 7.9 fb1 at higher energies, corresponding to more than 10 million Bs events. Recent results based on ~20% of these data will be presented, and prospects for future possibilities will be discussed.
Reference:
K.Kinoshita. Strange Beauty and Other Beasts from Upsilon(5S) at Belle http://arxiv.org/abs/1005.3893.
As part of the evaluation of my longfocal, nonachromatic refractor of the type developed during the first century, i.e., the 17th century, of optical astronomy, I have observed 175 double and multiple stars. About a year ago, after having observed most of these binary stars visually, I decided to see if it would be possible to measure their position angles and separations. Thus, I built a micrometer and began a program to determine if and how accurately I could measure the characteristics of these binaries. To my great surprise, the average error of the measured position angles is only 2 degrees and that of the separations is only 1 arcsecond values that are almost a good as modern measurements. These results further indicate that these very early and relatively primitive telescopes were much better that modern astronomical historians believe.
References:
The Performance Characteristics of 17th Century LongFocus, Non
Achromatic Refractors, Journal of the Antique Telescope Society, Issue
No. 31 Winter 2010, pp 317.
Thursday
April 1, 2010
7:008:30 P.M.
ILB 140
INVITATION
SLIDES
Thursday
April 1, 2010
4:005:00 P.M.
ILB 250
INVITATION
SLIDES
As soon as the Copernican revolution made humanity aware that the Earth is one planet among many, speculation began about the possibility that other planets might be inhabited. The main focus of interest always has been Mars, with the most Earthlike surface conditions of any planet. Robot orbiters and rovers have recently found clear evidence that Mars was once wetter and warmer than at present. In addition, Viking Mars lander soil test results from the 1970s indicated possible biological activity, and some investigators believe
Mars rock ALH84001 contains fossil microbes plus their metabolic products.
Beyond Mars, there is evidence for liquid water under ice crusts on Jupiter's moons Europa and Ganymede and Saturn's moon Enceladus, as well as abundant organic compounds in the atmosphere and on the surface of Saturn's moon Titan. Could any of these worlds harbor Earthlike, waterandcarbon based life? Astrobiology research and planetary exploration may reveal answers within just a few decades
References:
"Horizons" 11th edition, 2009, Seeds and Backman, Chapter 20
"Foundations of Astronomy", 11th edition, 2010, Seeds and Backman,
Chapter 26
"Search for Life in the Universe", Goldsmith and Owen, 3rd edition
The SOFIA observatory, presently undergoing a series of test flights leading to the start of scientific observations in mid2010, is a 2.5meter telescope mounted in a heavily modified Boeing 747SP aircraft. History of the project, details of its current status, and SOFIA's scientific promise as the premier world infrared and submillimeter observatory for the next 20 years will be presented.
References: http://www.sofia.usra.edu/ http://arxiv.org/abs/0905.4271
A ``Mesonet'' is a meteorological term meaning a network of weather stations that are spaced between 1 and 100 km apart. The University of South Alabama has operated its own Mesonet since 2006. The network currently consists of 16
Thursday
February 25, 2010
4:005:00 P.M.
ILB 250
INVITATION
SLIDES
PUBLIC LECTURE
Tuesday
November 17, 2009
7:008:30 P.M.
HUMB 150
INVITATION
SLIDES stations and will soon be expanded to 26 stations located in the coastal and nearcoastal counties of Mississippi, Alabama, and the Florida Panhandle. The spacing between stations ranges from 5.4 to 55.6 km with an average of about
30 km. Each station observes 14 meteorological parameters every minute.
Archived and (near) realtime data are available on our web site
(http://chiliweb.southalabama.edu/) for research, teaching, and forecasting purposes. Data uses are not limited to meteorology; a wide range of disciplines use weather data including agricultural interests, hydrologists and civil engineers, biologists and environmentalists, chemical companies, and more.
Many interesting weather phenomena and basic physical principles that apply in the atmosphere have been observed during the 3year existence of the network. In this presentation, the configuration of the weather stations, the data collected, and the data flow will be explained. Several interesting atmospheric phenomena including nocturnal inversions, seabreezes, and tropical storms will be described with the aid of weather station data.
References:
Kimball, Sytske K, Madhuri S. Mulekar, Shailer Cummings, Jack
Stamates, 2010: The University of South Alabama mesonet and coastal observing system: A technical and statistical overview. Journal of
Atmospheric and Oceanic Technology. Conditionally accepted for publication
Kimball, Sytske K, 2008: Structure and evolution of rainfall in numerically simulated landfalling hurricanes. Monthly Weather Review,
136, 3822 3847
Jeffrey M. Medlin, Sytske K. Kimball, and Keith G. Blackwell, 2007:
Radar and rain gauge analysis of the extreme rainfall during Hurricane
Danny's (1997) landfall. Monthly Weather Review, 135, 1869 1888
Gravitational waves are commonly referred as "ripples in the fabric of space time". They are produced by some of the most energetic and dramatic phenomena in the cosmos, including black holes, neutron stars and supernovae. The Laser Interferometer Gravitationalwave Observatory is on course to detect gravitational waves by using a device called laser interferometer, in which the time it takes light to travel between suspended mirrors is measured with high precision using controlled laser light. The two
LIGO interferometers are the world's largest precision optical instruments and among the most sensitive scientific instruments on the planet. The discovery of gravitational waves will help to address a number of fundamental questions in physics, from the evolution of stars and galaxies to the origin of dark energy and the nature of spacetime itself. These developments will open an exciting new window on the Universe, heralding the arrival of gravitational wave astronomy as a revolutionary, new observational field.
References:
Nature Physics
Thursday
October 22, 2009
4:00 PM
ILB Room 250
INVITATION
SLIDES
Thursday
September 24, 2009
PRD 80, 047101, 2009
PRD 80, 042003, 2009
The millimeterwave and terahertz regions of the electromagnetic spectrum have a long and rich history in the area of highresolution, gasphase molecular spectroscopy that is based on wellestablished physics and the continuous advancement of technology over the past 40 years. This has led to the detection of molecules in space and the ability to monitor molecules in the upper atmosphere that are associated with stratospheric ozone chemistry. This spectral region also possesses a unique combination of attributes that include high transmission through most dielectric materials along with the ability to develop imaging systems, properties associated with the microwave and infrared/optical regions of the spectrum, respectively. Due to these advantages, several terrestrial applications under development include radar systems for the standoff detection of human vital signs for triage and imaging systems for nondestructive evaluation. However, progress in the development of these applications remains slow due to the lack of affordable commercial technologies, leading to both technological and scientific gaps. This talk will discuss the basic underlying physics for each of these applications as well as a discussion of emerging technologies and commercial opportunities.
References:
D. T. Petkie, C. Benton, E. Bryan, Millimeterwave radar for vital signs sensing, Proceedings of SPIE: Radar Sensor Technology XIII, 7308 ,
73080A73080A5 (2009).
D. T. Petkie, C. Casto, F. C. De Lucia , S. R. Murrill, B. Redman , R. L.
Espinola , C. C. Franck, E. L. Jacobs , S. T. Griffin, C. E. Halford, J.
Reynolds, S. OBrien, and D. Tofsted, Active and Passive Imaging in the
THz Spectral Region: Phenomenology, Dynamic Range, Modes, and
Illumination, Journal of the Optical Society of America B, 25, 15231531
(2008).
D. T. Petkie, P. A. Helminger, B. P. Winnewisser, M. Winnewisser, K.
W. Jucks, and F. C. De Lucia, The Simulation of Infrared Bands from the
Analyses of Rotational Spectra: The 22 \mu Bands 2V9V9 abd V5V9 of HNO3, Journal of Quantitative Spectroscopy and Radiative Transfer,
92(2), 129141 (2005).
There are four known forces in nature. All of them can be described by a class
4:00 PM
ILB Room 250
INVITATION
SLIDES
Thursday
April 16, 2009
4:00 PM
ILB Room 250
INVITATION
SLIDES
Thursday of theories called Gauge Theories. Fiber bundles are the mathematical structures behind gauge theories. In this colloquium, I will first explain what a gauge theory is using electromagnetic theory as an example and will also explain nonabelian gauge theories using Quantum ChromoDynamics as an example. After that I will explain the idea of gauge invariance and the consequence of requiring it in a theory. Next I will explain what fiber bundles are with some example. After that I will make connection between the fiber bundle structure and gauge theories. I will end with some current research problems in the field of research.
References:
Equivalence of Minkowski and Euclidean Field Theory Solutions
Authors: Khin Maung Maung, Charles A. Hill, Michael T. Hill, George
DeRise arXiv:hepph/0302228
A collaboration of physicists and computer scientists from U.S. universities and national laboratories has since 1999 conducted a multifaceted R&D program aimed at building a national gridbased "cyberinfrastructure" to serve large scale scientific research. This collaboration led to the creation of Open Science
Grid consisting of more than 75 sites, 30,000 CPUs and serving particle physics, gravitational wave searches, digital astronomy, genome databases, nanoscience, functional magnetic resonance imaging, etc. OSG also links campus and regional grids and is a major component of the Worldwide LHC
Computing Grid (WLCG) that handles the massive computing and storage needs of experiments at the Large Hadron Collider. This collaborative work has provided a wealth of results, including powerful new Grid tools and services; a uniform grid middleware packaging scheme (the Virtual Data
Toolkit) that simplifies grid deployment across many sites; integration of complex Grid tools and services in large science applications; multiple education and outreach projects; and new approaches to integrating advanced network infrastructure in scientific computing applications.
References:
Paul Avery, "Open Science Grid: Building and Sustaining General
Cyberinfrastructure Using a Collaborative Approach", Selected Papers from the Conference on Cyberinfrastructure for Collaboration and
Innovation (Jan. 2829, 2007), First Monday, firstmonday.org, June
2007.
October 23, 2008
4:00 PM
ILB Room 250
INVITATION
SLIDES
Thursday
October 16, 2008
4:00 PM
ILB Room 250
INVITATION
SLIDES
Thursday
Dark energy appears to be the dominant component of the present mass density of the Universe, yet there is no persuasive theoretical explanation for its existence or magnitude. While the simplest explanation might be Einstein's cosmological constant, there are other possibilities, including dynamical dark energy, modification of general relativity, or back reactions of inhomogeneities. Many feel that nothing short of a revolution in our understanding of physics will be required to solve the dark energy issue. After framing the darkenergy problem, I will discuss possible theoretical solutions, as well as an observational program to study the properties of dark energy.
References:
Report of the Dark Energy Task Force. Andreas Albrecht et al.
FERMILABFN0793A, Sep 2006. ePrint: astroph/0609591 http://imagine.gsfc.nasa.gov/docs/science/mysteries_l1/dark_energy.html
Particle physics has been extremely successful in establishing the constituents of matters, understanding the role of symmetries, and building the standard model of particles and interactions that explains current collider observations with exquisite precision. We are now poised to open a window on a new unexplored energy region called the TERASCALE where we expect a revolution in our understanding of physics and unequaled opportunity for discovery. The Standard Model of particle physics predicts the existence of the
Higgs boson, a particle that carries the Higgs field. The Higgs field, which is expected to permeate the entire Universe, explains why matter has mass since as a massless particle passes through the Higgs field it gains mass. I will present the latest results from the CDF experiment at the Tevatron on the search for the Higgs boson and trace the discovery path from the Tevatron to the next high energy frontier at the Large Hadron Collider.
References:
Search for the Higgs boson in events with missing transverse energy and b quark jets produced in protonantiproton collisions at s**(1/2)=1.96
TeV. T. Aaltonen et al., The CDF Collaboration, Phys. Rev. Lett. 100,
211801 (2008)
Search for Standard Model Higgs Bosons Produced in Association with
W Bosons T. Aaltonen et al., The CDF Collaboration, Phys. Rev. Lett.
100, 041801 (2008)
September 18, 2008
4:00 PM
ILB Room 250
INVITATION
SLIDES
Friday
March 28, 2008
4:00 PM
ILB Room 250
INVITATION
SLIDES
Thursday
March 20, 2008
4:00 PM
ILB Room 250
I shall give a very general overview of experimental particle physics, where we started from and where we are today. I will concentrate on the major collider detectors in the world at the Fermi National Accelerator Laboratory in
Batavia, Illinois and the European Organization for Nuclear Research (CERN) in Geneva, Switzerland. I shall also emphasize why this research is so important to the growth of a society and how undergraduate students in any science discipline can learn and contribute to this effort.
References:
Measurement of the t antit production cross section in p antip collisions at s**(1/2) = 1.96TeV. By D0 Collaboration (V.M. Abazov et al.).
Published in Phys.Rev.Lett.100:192004,2008.
CMS technical design report, volume II: Physics performance. By CMS
Collaboration (G.L. Bayatian et al.). Published in J.Phys.G34:995
1579,2007.
The formalism of quantum open systems, as originally put forth by Feynman and Vernon, provides a framework for tackling many difficult problems in quantum mechanics. Key among these are (1) extending the kinetic theory of
Brownian motion into the quantum domain and (2) giving exact models of dissipation in quantum systems, given that unitary dynamics would typically forbid energy loss and irreversible dynamics. This talk will give a general introduction to Quantum Brownian Motion and discuss some of the more recent results.
References:
R. P. Feynman, F. L. Vernon, Ann. Phys. (N.Y.) 24, 118 (1963) A. O.
Caldeira, A. J. Leggett, Physica A 121, 587 (1983). B. L. Hu, J. P. Paz and Y. Zhang, Phys. Rev. D 45, 2843 (1992). C. H. Fleming, B. L. Hu,
A. Roura, arXiv:0705.2766 [quantph]
In recent years Grid Computing has evolved into a reliable and robust means of providing scientific communities with convenient access to unprecedented amounts of computing. In the US the Open Science Grid (OSG) was developed in part to support one these communities, namely scientists working on the
Large Hadron Collider (LHC) experiments at CERN near Geneva,
INVITATION
SLIDES
Thursday
October 25, 2007
4:00 PM
ILB Room 250
INVITATION
SLIDES
Friday
Switzerland. With help of grid computing these communities are now poised to explore some of the most profound questions about the nature of mater, energy and the very fabric of space time. In this talk I will introduce the concept of grid computing. I will then describe a current implementation, the OSG highlighting its most important components and illustrate how these together form a computing grid. I will then describing how the OSG and its European counterpart the EGEE were used in a recent large scale worldwide computing and data movement exercise conducted by the Compact Muon Solenoid experiment one of the four LHC experiments.
References:
I. Foster, J. Gireraltowski, S. Gose, N. Maltsev, E. May, A. Rodriguez, et al., 2004, The Grid2003 Production Grid: Principles and Practice
Nonlinear gyrokinetic numerical calculations have been performed with the threedimensional, global, toroidal, nonlinear, particleincell, deltaf, massively parallel UClaCANada (UCAN) code. Their purpose is to study the effects of the parallel nonlinearity and of strong (externally imposed) sheared flow radial gradient corrections on ion temperature gradient driven turbulence
(ITGDT) in tokamaks. These calculations show that the strong flow corrections reinforce the powerful stabilizing effects of sheared poloidal flows on the saturation level of the fluctuations and on the heat flux they produce. The re activated parallel nonlinearity, in combination with zonal flows generated through Reynolds stress by the fluctuations themselves, leads to an apparent quantitative reduction in saturation level and heat flux. This reduction does however decrease with increasing system size at fixed ion Larmor radius, i.e.
with diminishing rho.
References:
L. Villard, S.J. Allfrey, A. Bottino, M. Brunetti, G.L. Falchetto, V.
Grandgirard, R. Hatzky, J. Nhrenberg, A.G. Peeters, O. Sauter, S. Sorge and J. Vaclavik, Full radius linear and nonlinear gyrokinetic simulations for tokamaks and stellarators: zonal flows, applied E x B flows, trapped electrons and finite beta, Nucl. Fusion, 44 No 1 (January 2004) 172180
L. Villard, P Angelino, A Bottino, S J Allfrey, R Hatzky, Y Idomura, O
Sauter and T M Tran, "First principles based simulations of instabilities and turbulence", 2004 Plasma Phys. Control. Fusion, 46 B51B62.
November 2, 2007
3:30 PM
ILB Room 240
INVITATION
SLIDES
Thursday
November 15, 2007
4:00 PM
ILB Room 250
INVITATION
SLIDES
I will begin with an introduction to the Standard Model(SM) of particle physics. Though highly successful, there are many unanswered questions in the
Standard Model. It is believed that some "new physics"(NP) must be there to resolve the SM puzzles. I will discuss how one can search for this new physics at present and future experiments such as the B factories and the LHC.
References:
Is there New Physics in B Decays? Alakabha Datta (Mississippi U.) .
UMISSHEP200701, Jan 2007. 8pp. Talk given at 2nd Annual Theory
Canada 2 Conference, Waterloo, Ontario, Canada, 710 Jun 2006. e
Print: hepph/0701172
The B to pi K puzzle and new physics. Seungwon Baek, Philippe Hamel,
David London (Montreal U.) , Alakabha Datta (Toronto U.) , Denis A.
Suprun (Brookhaven) . UDEMGPPTH04128, Dec 2004. 4pp.
Published in Phys.Rev.D71:057502,2005. ePrint: hepph/0412086
Luminescence induced by mechanical stress is called mechanoluminescence
(ML) or triboluminescence (TL). TL is a commonly encountered phenomenon, with approximately 50% of known crystals exhibiting such tendencies. The
® Lifesavers.
If stressed, atriboluminescent crystal produces local regions with charge imbalances. Several mechanisms may then occur to produce light. It is possible for the charge imbalance to be sufficient to cause a dielectric breakdown of the surrounding gas, producing light. It is also possible for the emission of light from a dielectric breakdown to excite the triboluminescent material. A charge imbalance can also generate electroluminescence. The impacts are a possible source of stress to the crystal and create TL light.
References:
N.P. Bergeron, W.A. Hollerman, S.M. Goedeke, M. Hovater, W. Hubbs,
A. Fichum, R.J. Moore, S.W. Allison, and D.L. Edwards, Experimental
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