Events at Physics |
Events During the Week of December 11th through December 18th, 2011
Monday, December 12th, 2011
- Plasma Physics (Physics/ECE/NE 922) Seminar
- TBD
- Time: 12:05 pm
- Place: 2317 Engineering Hall
- Speaker: Gennady Fiksel, University of Rochester
- Condensed Matter Theory Group Seminar
- Magnon spectrum in a spiral magnetic order on the pyrochlore lattice
- Time: 4:30 pm
- Place: 5310 Chamberlin
- Speaker: Eunsong Choi, UW-Madison
- Host: Perkins
Tuesday, December 13th, 2011
- Chaos & Complex Systems Seminar
- Dimensional Analysis: Can a trick to help physics students pass exams provide insight into the Nature of the Universe?
- Time: 12:05 pm
- Place: 4274 Chamberlin
- Speaker: Jim Blair, Milton and Edgewood College
- Abstract: 1- Equations, Units and Dimensions 2- The Fundamentals: Mass, Length and Time. (and the Derived: all the others.) 3- Some Anomalies: Fractional Exponents? Different things with the Same Dimensions? The same things with Different Dimensions? 4- Add Charge, Temperature and Angle to the Fundamentals to resolve the anomalies (But the units are arbitrary and not explainable to Aliens.) 5- Change the Fundamentals to Angle, Charge, Mass, Velocity, Action, and Entropy, and make a unit system that Everyone can understand. (even Bug Eyed Monsters and Little Green Men all over the Universe) 6- Another way to look at the Heisenberg Uncertainty Principle.
- Host: Sprott
- Theory Seminar (High Energy/Cosmology)
- Spotting an invisible Higgs at the 7 TeV LHC
- Time: 4:00 pm
- Place: 5280 Chamberlin Hall
- Speaker: Jessie Shelton, Yale University
- Abstract: Simple extensions of the Standard Model -- for example, to accommodate dark matter -- can easily induce a dominant decay of a light Standard Model-like Higgs into invisible particles. I will discuss the reach of the 7 TeV LHC for an invisible Higgs. I will talk about three different search channels, and show prospects for 2012.
Wednesday, December 14th, 2011
- Department Meeting
- Canceled
- Time: 12:15 pm
- Place: 5310 Chamberlin Hall
- The Department meeting has been canceled.
Thursday, December 15th, 2011
- Last Day of Class
- R. G. Herb Condensed Matter Seminar
- Orbital and magnetic ordering in ZnV2O4
- Time: 10:00 am
- Place: 5310 Chamberlin
- Speaker: Yasuyuki Kato, Los Alamos National Laboratory
- Abstract: Spinel group comprise corner sharing tetrahedra and constitute paradigmatic examples of geometrically frustrated lattices. The spinel compound, ZnV2O4, is a Mott insulator with a rather small charge gap that undergoes a structural cubic to tetragonal transition at T=50(K). A magnetic transition at a lower temperature of T=40(K) has also been reported for this compound. The magnetic ordering corresponds to up-up-down-down spin configurations for chains oriented along the yz and zx directions. The origin of this magnetic ordering and the lack of orbital ordering in this material has been an open problem for several decades. The main obstacle was the lack of controlled and unbiased approaches for solving the correlated and frustrated model. I will introduce a novel quantum Monte Carlo method that can simulate the three-band Hubbard model relevant for these materials without generating any serious problem. We will see that this unbiased approach not only explains the observed magnetic ordering but also the lack of orbital ordering.
- Host: Perkins
- Astronomy Colloquium
- AGB Dust Production in the Local Group
- Time: 3:30 pm - 5:00 pm
- Place: 4421 Sterling Hall
- Speaker: Martha Boyer, Space Telescope Science Institute
- Abstract: There are two known ways to create new dust to input into the interstellar medium: in supernova explosions and in the circumstellar envelopes of evolved stars. Massive evolved stars such as red supergiants produce a lot of dust, but Asymptotic Giant Branch (AGB) stars are thought to be the dominant stellar creators of dust at both low and high redshift (z), possibly even in the host galaxy of one of the most distant quasars (z=6.4; Valiante et al. 2009). Using observations from the Spitzer Space Telescope, we can for the first time study entire populations of AGB stars and quantify the total AGB dust production in Local Group Galaxies. Here, I discuss recent work on dust production in nearby globular clusters and dwarf galaxies, with particular focus on the Magellanic Clouds.
- Host: Barbara Whitney
Friday, December 16th, 2011
- No events scheduled