Events at Physics |
Events During the Week of January 18th through January 25th, 2015
Monday, January 19th, 2015
- No events scheduled
Tuesday, January 20th, 2015
- Chaos & Complex Systems Seminar
- The passenger pigeon: Why it went extinct, and can we resurrect it?
- Time: 12:05 pm - 1:00 pm
- Place: 4274 Chamberlin (refreshments will be served)
- Speaker: Stan Temple, Nelson Institute
- Abstract: The passenger pigeon declined from billions to none in the span of 50 years. Stan Temple analyses how this incredible collapse could have happened. And now, 100 years after the species' extinction, advances in biotechnology have led to visions of resurrecting the species. Could we? Should we?
- Host: Clint Sprott
- NPAC (Nuclear/Particle/Astro/Cosmo) Forum
- Faculty Candidate Seminar
- The LUX and LZ Dark Matter Experiments
- Time: 4:00 pm - 5:00 pm
- Place: 4274 Chamberlin Hall
- Speaker: Kevin O'Sullivan, Yale
- Abstract: Evidence from galactic rotation curves, gravitational lensing, the cosmic microwave background, and other cosmological studies point to the existence of exotic non-luminous matter, referred to as dark matter. In spite of the strong indirect evidence for the existence of dark matter, it's composition remains unknown. One of the most promising putative dark matter candidates are Weakly Interacting Massive Particles (WIMPs) which would be observable through their scatters off ordinary matter. The Large Underground Xenon Experiment (LUX) searches for WIMPs using a large, two-phase Xenon detector operating at the Sanford Underground Research Facility (SURF). The first science run of LUX consisted of 85.3 live days with 118 kg of fiducial mass. A pro file-likelihood analysis of the data shows consistency with the background-only hypothesis, allowing a 90% confidence limit to be set on the spin-independent WIMP-nucleon elastic scattering with an upper limit on the cross section of 7.6x10^46 cm^2 at a WIMP mass of 33 GeV. LUX is continuing to take data and is working on a low-threshold analysis to search for light WIMPs (< 6 GeV in mass). Concurrently design work is ongoing for the LUX-ZEPLIN (LZ) project which will be two orders of magnitude more sensitive than LUX.
- Host: Dasu
Wednesday, January 21st, 2015
- Department Meeting
- Time: 12:15 pm
- Place: 5310 Chamberlin Hall
- NPAC (Nuclear/Particle/Astro/Cosmo) Forum
- Faculty Candidate Seminar
- The non-thermal Universe
- Time: 4:00 pm - 5:00 pm
- Place: 4274 Chamberlin Hall
- Speaker: Markus Ahlers, UW - Madison
- Abstract: One of the most puzzling observations of modern astronomy is the existence of very high-energetic messengers in the form of cosmic rays, gamma-rays and cosmic neutrinos. These phenomena are related to non-thermal processes in the Universe which in most cases are barely understood. The multi-messenger observations contain not only information about particle production processes in the sources but also the cosmic evolution of source populations and various propagation effects in extragalactic and Galactic environments. I will highlight how recent observations in cosmic ray, gamma-ray and neutrino astronomy provide new clues or support existing models of the underlying physics of high-energy phenomena in the Universe.
- Host: Dasu
- Public event
- Particle Fever screening
- Time: 7:00 pm - 9:00 pm
- Place: Marquee Theater, Union South
- Speaker: Sridhara Dasu & Wesley Smith, UW–Madison
- Abstract:
On Wednesday, January 21, a special edition of Wednesday Nite @ the Lab will feature a screening of Particle Fever at the Marquee Theater in Union South, UW–Madison. The film follows six brilliant scientists during the launch of the Large Hadron Collider, marking the start-up of the biggest and most expensive experiment in the history of the planet. 10,000 scientists from over 100 countries join forces in pursuit of a single goal: to recreate conditions that existed just moments after the Big Bang and find the Higgs boson, potentially explaining the origin of all matter. Particle Fever is a celebration of discovery, revealing the very human stories behind the tale of this epic experiment.
UW physics professors that had key roles in the Higgs discovery will give an introduction to the film. The screening is presented by the Physics Department, Wednesday Nite @ the Lab, and WUD Film.
Thursday, January 22nd, 2015
- Atomic Physics Seminar
- Faculty Candidate Seminar
- Magnetism, rotons, and beyond: engineering atomic systems with lattice shaking
- Time: 4:00 pm - 5:00 pm
- Place: 4274 Chamberlin Hall
- Speaker: Colin Parker, University of Chicago, James Franck Institute and Department of Physics
- Abstract: Conventional methods of quantum simulation rely on kinectic energy determined by free particle dispersions or simple sinusoidal optical lattices. Solid state sytems, by contrast, exhibit a plethora of band structures which differ quantitatively, qualitatively, and even topologically. To what extent does this variety explain the many electronic phenomena observed in these materials? Here we address this question by subjecting an otherwise simple Bose superfluid to a customized band structure engineered by dynamically phase modulating (shaking) an optical lattice. The engineered dispersion contains two minima which we associate to a pseudospin degree of freedom. Surprisingly, in such a system the Bose superfluid exhibits many new behaviors. The psuedospin develops a ferromagnetic order, which can lead to polarization of the entire sample or to sub-division into polarized domains. The excitations of the system also exhibit the roton-maxon structure associated with strong interactions in superfluid helium.
- Host: Coppersmith
Friday, January 23rd, 2015
- Physics Department Colloquium
- Entanglement, Bell's Inequality, Trapped Ions, and Quantum Computing
- Time: 3:30 pm - 4:30 pm
- Place: 2241 Chamberlin Hall (coffee at 4:30 pm)
- Speaker: Chris Monroe, JQI, University of Maryland
- Abstract: Quantum entanglement is the central resource behind Quantum Information Science, and the quantification of entanglement following John Bell's famous inequalities 50 years ago have become tremendously important in the field. Some of the cleanest demonstrations of Bell-Inequality violations have been measured in laser-cooled trapped atomic ions, an experimental platform that has become the standard for quantum bits in a quantum information processor. I will summarize the state-of-the-art in generating entangled states in several trapped ions for quantum information processing and also the quantum simulation of models of quantum magnetism. Scaling to larger numbers can be accomplished by coupling trapped ion qubits to optical photons, where entanglement can be formed over remote distances for applications in quantum communication, quantum teleportation, and distributed quantum computation. By employing such a modular and reconfigurable architecture, it should be possible to scale up ion trap quantum networks to useful dimensions, and hopefully extend Bell's seminal work to the characterization of massive entangled states that cannot even be represented using a classical computer.
- Host: Walker