Fall 2011 Colloquium Series
Sep 29, 2011
Oct 6, 2011
Laboratoire Charles Coulomb, CNRS and Universite Montpellier 2, Montpellier, France
A quick overview of open quantum system
Whatever care is exercised to protect it, a quantum system Q is always interaction with its environment E. Information about Q is always leaking into the correlation building up between Q and E: everything happens as if the environment was constantly watching the system, and the mere possibility that this information could be retrieved, really or virtually, is enough to destroy the quantum coherence of the system. I will present a quick survey of different approaches to describe this lost of coherence induced by the environment and illustrate them on different systems.
Oct 13, 2011
University of Oregon, Physics
"Dude, where's my Higgs?"
The performance and status of the LHC accelerator and ATLAS detector during 2011 will be described with particular attention given to the dramatic luminosity increase achieved this year. The current status of the ATLAS Higgs searches will be reviewed, along with prospects for the near future.
Oct 20, 2011
University of Hawaii
Neutrinos: Yesterday, Today and Tomorrow
I will describe the history of the discovery/invention of neutrinos, starting with the discovery of radioactivity by Henri
Becquerel almost 115 years ago. It took the next 35 years before the neutrino was invented and another 25 years before it could be "discovered" experimentally. From 1956 to 2000 the remaining two kinds of neutrinos were found, and the story of neutrinos is intimately tied to the history of particle physics itself over this period. Along the way, we will cover the subject of neutrino oscillations or neutrino metamorphosis, which is related to the neutrino masses and mixing. We disucuss the wide variety of sources of neutrinos ranging from the earth and the sun to nuclear reactors and accelerators, as well
as supernova (and other astrophysical objects) and the early universe.
Finally some applications of neutrinos which are very speculative and futuristic will be briefly described.
Becquerel almost 115 years ago. It took the next 35 years before the neutrino was invented and another 25 years before it could be "discovered" experimentally. From 1956 to 2000 the remaining two kinds of neutrinos were found, and the story of neutrinos is intimately tied to the history of particle physics itself over this period. Along the way, we will cover the subject of neutrino oscillations or neutrino metamorphosis, which is related to the neutrino masses and mixing. We disucuss the wide variety of sources of neutrinos ranging from the earth and the sun to nuclear reactors and accelerators, as well
as supernova (and other astrophysical objects) and the early universe.
Finally some applications of neutrinos which are very speculative and futuristic will be briefly described.
Oct 27, 2011
University of Oregon, Physics
Cavity optomechanics: Controlling mechanical motion with light
It is well known that mechanical forces of light can be used for the manipulation of mechanical motion in microscopic systems. Notable examples include laser cooling and laser tweezers, techniques that have opened up new frontiers for scientific exploration. In this talk, I will discuss recent development on the use of mechanical forces of light to control mechanical motion in macroscopic systems. As an example of potential applications, I will also discuss our current work on quantum state mapping between optical and motional states for quantum internets.
Nov 3, 2011
Genetics and Intelligence: a project I started during my sabbatical
How do genes affect cognitive ability? We may soon have some answers to this ancient question. I begin with a brief review of psychometric measurements of intelligence, introducing the idea of a "general factor" or IQ score. The main results concern the stability, validity (predictive power), and heritability of adult IQ. Next, I discuss ongoing Genome Wide Association Studies which investigate the genetic basis of intelligence. My work on this project is in collaboration with BGI, one of the largest genomics labs in the world. Due mainly to the rapidly decreasing cost of sequencing, it is likely that within the next 5-10 years we will identify genes which account for a significant fraction of total IQ variation. We are currently seeking volunteers for a study of high cognitive ability. Participants will receive free genotyping and tools with which to explore their genomes.
Nov 10, 2011
All These Wavelengths are Yours, Maybe
In this millennium experimental astrophysics has undergone a substantial transformation moving away from the realm of botany/morphology and into the realn of precision physics where excellent instrumentation now exists at most all wavelengths. Within that theme, this talk will focus on three basic points:
1) A historical narrative of the rise of precision instrumentation in Experimental Astrophysics and the discovery space that is opened by this instrumentation
2) A discussion of Markarian 266 - an extremely complex object which now has the distinction of being the most targeted object in the Universe in terms of being observed at all wavelengths with precise instrumentation. These new precision observations have completely overwhelmed the observing team and this serves as an important object lesson.
3) The inevitable downside of this move towards precise instrumentation is the high cost of building, launching. maintaining and operating it. As a result, the NSF has directly informed "Astronomy" to expect closure of facilities in the very near future. Thus, right when the community has made this important transformation there seems to be no ability to maintain it thus forcing Astronomy to become an incremental knowledge field, which basically sucks on all levels
1) A historical narrative of the rise of precision instrumentation in Experimental Astrophysics and the discovery space that is opened by this instrumentation
2) A discussion of Markarian 266 - an extremely complex object which now has the distinction of being the most targeted object in the Universe in terms of being observed at all wavelengths with precise instrumentation. These new precision observations have completely overwhelmed the observing team and this serves as an important object lesson.
3) The inevitable downside of this move towards precise instrumentation is the high cost of building, launching. maintaining and operating it. As a result, the NSF has directly informed "Astronomy" to expect closure of facilities in the very near future. Thus, right when the community has made this important transformation there seems to be no ability to maintain it thus forcing Astronomy to become an incremental knowledge field, which basically sucks on all levels
Nov 17, 2011
University of Illinois
Solar Energy and the Defect Physics of CuInSe2
This talk begins with a brief review of the current status of photovoltaic energy technology and the major players that are likely to contribute to meeting our future energy demands. PV is growing at 40% per year (one recent year up to 80%) and is now contributing a significant amount to our needs. We will then look at the materials science and physics of one of the most promising semiconductors, CuInSe2 (and related materials). We will consider the observed behaviors of the device in which the material is applied and what those behaviors imply about the material. We will then consider optoelectronic data obtained by a variety of techniques. This includes a comparison of scanning tunneling spectroscopy data on two materials, CuInSe2 and AgInSe2 that shows dramatic differences in the local defects and how they impact the density of states around the band edges. This is then connected to photoluminescence and other measurement results as well as to device performance. The conclusion of the talk is that the material appears to be limited by the density of states around the band edges and by band tails in particular. Therefore when we optimize devices we need to think more about amorphous silicon as a previous example than about GaAs.
Dec 1, 2011
