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Events on Thursday, September 5th, 2013
 R. G. Herb Condensed Matter Seminar
 Random Matrix Approach to Understand the Statistical Properties of Complex Wave Scattering Systems
 Time: 10:00 am
 Place: 5310 Chamberlin
 Speaker: JenHao Yeh, University of Maryland
 Abstract: There is great interest in the quantum/wave properties of systems that show chaos in the classical (short wavelength, or ray) limit. These wave chaotic systems appear in many contexts: nuclear physics, acoustics, twodimensional quantum dots, and electromagnetic enclosures. Initiated by the need to understand the energy levels of complicated nuclei, random matrix theory (RMT) has been applied to successfully predict universal properties of these complicated wavescattering systems through the statistical description of their eigenvalues, eigenfunctions, impedance matrices, and scattering matrices. For understanding the properties of practical systems, researchers at Maryland have developed the random coupling model (RCM) to offer a complete statistical model which utilizes a simple additive formula in terms of impedance matrices to combine the predictions of RMT and the nonuniversal systemspecific features in practical systems. We have carried out experimental tests of the random coupling model in microwave cavities, including a superconducting microwave cavity acting as a low loss environment. The results demonstrate the nonuniversal features, such as the radiation impedance and the short orbits, and the universal fluctuations in wave properties, such as the scattering matrix elements and the impedance matrix elements, of complex wave scattering systems.
 Host: McDermott
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 Special Talk
 Massive Galaxies in the Early Universe: New Insights into Galaxy Formation and Evolution
 Time: 3:30 pm
 Place: 4421 Sterling Hall
 Speaker: Danilo Marchesini, Tufts University
 Abstract: In the past decade, our understanding of the galaxy population in the first 4 billion years of cosmic history (z>2) has improved significantly, thanks to the increasing ability to construct comprehensive snapshots (in time) from z=4 (when the universe was ~1.5 billion years old) to z=2. I will summarize our current knowledge of the (massive) galaxy population at z=24, with an emphasis on the results from the NEWFIRM MediumBand Survey, a large NOAO/Yale program which uses medium bandwidth filters in the nearinfrared to obtain wellsampled spectral energy distributions and highquality photometric redshifts at z>1.5 over 0.5 square degree. I will present recent results from the UltraVISTA and NMBSII, and preliminary results from ongoing followup spectroscopic programs.
 Host: Prof Elena D'Onghia
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