Events at Physics |
Events During the Week of September 14th through September 21st, 2008
Monday, September 15th, 2008
- Plasma Physics (Physics/ECE/NE 922) Seminar
- CANCELED
- Time: 12:05 pm
- Place: CANCELED
- Speaker: Amitava Bhattacharjee, University of New Hampshire
- Physics Department Seminar
- Canceled
- Time: 1:00 pm
- Place: Canceled
- Speaker: Saad Saleh, Bellaire Technology Center , Shell International Exploration & Production, Inc.
- Host: Physics Department
- Plasma Theory Seminar
- Canceled
- Time: 4:00 pm
- Place: Canceled
- Speaker: Amitava Bhattacharjee, University of New Hampshire, Dept of Physics
Tuesday, September 16th, 2008
- Chaos & Complex Systems Seminar
- What are your 'thinking genes' doing in a plant?
- Time: 12:05 pm
- Place: 4274 Chamberlin (Refreshments will be served)
- Speaker: Edgar Spalding, UW Department of Botany
- Abstract: It's hard to keep an open mind. If we don't shut down some possibilities, create certain boundaries, we'd never get anywhere through thought. But it's easy to go overboard and start throwing up blocks and dividers left and right to keep things simple and manageable. Excesses in this coping method inevitably run afoul of new facts and findings and then hindsight shows its waste. My presentation will be a story that exemplifies this folly of ours. The protagonist is a group of genes encoding protein molecules known as glutamate receptor channels. In our brains, they play fundamental signal-transmitting roles, chemically connecting one neuron to another. Their properties make learning and other higher cognitive functions possible. If ever there could be a molecule that sets sentient beings like us apart from the rest of the living world, the glutamate receptor channels might be it. So what on earth are genes encoding these 'molecules for thinking' doing in the DNA of plants? We have been researching this question with genetics, electrophysiology, and computerized image analysis. I will describe some of the progress we have made and what we may risk by letting conventional wisdom about plants and animals rule our thinking.
Wednesday, September 17th, 2008
- No events scheduled
Thursday, September 18th, 2008
- R. G. Herb Condensed Matter Seminar
- Quantum activation, scaling, and quantum measurements
- Time: 10:00 am
- Place: 5310 Chamberlin
- Speaker: Mark Dykman, Michigan State University
- Abstract: Familiar mechanisms of metastable decay are tunneling and thermal activation. We show that periodically modulated systems may display a different decay mechanism, quantum activation. Here, decay occurs via quantum fluctuations induced diffusion over a quasi-energy barrier. We study quantum activation for nonlinear oscillators and show its unexpected features. The decay rate displays scaling behavior near critical parameter values where metastable vibrational states disappear. We also show that the tunnel splitting of symmetric and antisymmetric vibrational states oscillates and changes sign with varying parameters. The results impose limitations on the characteristics of bifurcation amplifiers used in quantum measurements.
- Host: Susan Coppersmith
- Special Astronomy Colloquium at Noon
- The Small Magellanic Cloud Star Formation History
- Time: 12:00 pm
- Place: 3425 Sterling Hall
- Speaker: Elena Sabbi, STSci
- Abstract: The Small Magellanic Cloud (SMC) is a unique laboratory to study a wide range of astrophysical phenomena, from the birth and evolution of stars, through the physics of the multi-phase interstellar medium, to the dynamics and evolution of galaxies. At only 60 kpc from us, the SMC is the closest late-type dwarf galaxy with active star formation. With a present-day metal abundance about a factor eight lower than that of the Sun, the SMC allows to investigate the star formation processes in an environment typical of the formation of the types of galaxies that dominate the appearance of today's Universe. Hence the SMC is an important template for understanding the evolution of galaxies as an astrophysical system.<br>
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The properties of the SMC encouraged us to start a deep imaging survey using the exquisite capabilities of the Advanced Camera for Surveys (ACS) on board of the Hubble Space Telescope (HST) with the objective of investigate the properties of its stellar populations in the bar, the wing and the bridge, in the field as well as in intermediate and old star clusters and in HII star forming regions.<br>
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I will discuss the age-metallicity relation, the three dimensional structure of the SMC halo, the impact of local and global conditions on star formation, and the star formation history of this galaxy over the entire Hubble time, in the context of late-type dwarf galaxy evolution. Friday, September 19th, 2008
- Physics Department Seminar
- Galileo - The European Navigation Satellite System
- Time: 12:00 pm
- Place: 2241 Chamberlin (11:30 a.m. cookies and coffee)
- Speaker: Wilfried Bornemann, EADS Astrium, Munich Germany
- Abstract: Europe is building its own global navigation satellite system, providing a highly accurate, guaranteed global positing service under civilian control. It will be compatible and interoperable with GPS. By offering dual frequencies as standard, Galileo will deliver real-time positioning accuracy down to the meter range which is unprecedented for a publicly available system. It will guarantee availability of the service under all but the most extreme circumstances and will inform users within seconds of a failure of any satellite. This makes Galileo suitable for applications where safety is crucial. The presentation will address Galileo architecture and implementation aspects along with technology developments and will provide an overview of the program status, including anecdotes from the multi-national political process entailed by attempting a technical undertaking of such magnitude within the European Union. Dr. Wilfried Bornemann is responsible for Galileo Coordination at EADS Astrium in Munich, Germany, which is the prime contractor of the Galileo space segment for the ongoing development phase.
- Host: Jim Reardon
- Physics Department Colloquium
- Rapture of the Deep Sky
- Time: 4:00 pm
- Place: 2241 Chamberlin Hall (coffee at 3:30 pm)
- Speaker: Professor Melville P. Ulmer, Department of Physics & Astronomy, Northwestern University
- Abstract: Astronomers have become "drunk" like deep sea divers with observations of the deep (faint object) sky. This has lead to a host of telescopes that enable us to see fainter and fainter than ever before. The majority of astronomers have focused on finding the most distant objects, but exciting science can be done by going fainter besides pushing to the edges of the Universe. I will show how I have taken advantage of the ability to detect faint sky objects to study clusters of galaxies. These are exceedingly interesting objects that allow us to engage some of the key issues of physics today, such as Dark Energy and Cold Dark Matter (CDM). Clusters are also natural places to learn about the origin and evolution of both galaxies and the large scale structure of the Universe. I will describe how clusters can be a used to address the nature of Dark Energy as well as what clusters already have to say about Dark Matter.
Bio: Mel Ulmer is a Fellow of the American Physical Society and of the Society of Photo-Optical Instrumentation Engineers. He is a member of the American Astronomical Society, the American Physical Society, the International Astronomical Union, and the Society of Photo-Optical Instrumentation Engineers, and the Royal Astronomical Society. He has served on executive councils for the high energy astrophysics divisions of both American Astronomical Society and the American Physical Society, as well as several NASA advisory and review panels. He has published over 250 articles in journals and conference proceeding on topics including the study of binary X-ray sources, pulsars, and the large scale structure of the Universe. He has also worked in areas of technology development and has written papers on GaN-based films, multilayer super-conducting tunnel junctions, X-ray mirror fabrication, and light weight optical mirror fabrication. He received a B.A.in Physics from The Johns Hopkins University ('65) and a Ph.D. in Physics (Bill Kraushaar advisor, '70) from The Univ of Wisconsin-Madison.
http://www.astro.northwestern.edu/~ulmer/ - Host: Barger