Events Archive

Dec
15
2011
Nanoscale Switching Behavior and Electronic Properties of Ultrathin Ferroelectric Structures
Dec
07
2011
"The biggest little molecules in Nature"
This colloquium will discuss recent theoretical predictions and experimental confirmation of two unusual classes of ultra-long-range molecules. One class involves a highly-excited Rydberg electron that manages to bind a distant ground state atom at thousands of Bohr radii. The other class involves the bizarre Efimov effect for three or four ground state atoms with resonant interactions. Implications for the behavior of ultracold quantum gases will be addressed.
Dec
07
2011
Analyzing 3-D stochastic dynamics in live cells
Advances in microscopy have enabled measurements in living cells, but there is a wealth of biologically relevant dynamical information contained in experimental data that has not been utilized.  Existing analysis methods either coarse grain too much or cannot overcome some technical challenges inherent to in vivo measurements. The importance of more fully utilizing information “hidden” in noisy 3D in vivo measurements will be emphasized in several problems.  In this talk, I demonstrate how recent advances in time series analysis can be used to estimate stochastic differential equations (SDEs) and construct hypothesis tests checking the...
Dec
06
2011
Analyzing 3-D stochastic dynamics in live cells
Advances in microscopy have enabled measurements in living cells, but there is a wealth of biologically relevant dynamical information contained in experimental data that has not been utilized.  Existing analysis methods either coarse grain too much or cannot overcome some technical challenges inherent to in vivo measurements. The importance of more fully utilizing information “hidden” in noisy 3D in vivo measurements will be emphasized in several problems.  In this talk, I demonstrate how recent advances in time series analysis can be used to estimate stochastic differential equations (SDEs) and construct hypothesis tests checking the consistency...
Dec
01
2011
NMR study of the dynamics of ³He atoms in dilution ³He-⁴He solid solutions
Nov
30
2011
Cosmic Information Theory and Analysis: IT from BIT, from BITs in IT
We consider the Universe to be fundamentally quantum and statistical, the many-paths/many-worlds information-theoretic story. This lecture uses Cosmic Information Theory and Analysis, CITA, as a unifying theme to explore the vast sweep  of our current ideas of the Universe and the experiments we use to probe them, ranging from the ultra-early beginnings to our far-future fate. I describe the intimate entanglement of theory with precision "first-light"  and other cosmic data, in particular from the satellite Planck and the Andes-based ACT. Such data are the BITs in IT informing us of the physics that defines the BIT of the Universe...
Nov
17
2011
Deriving reduced models for plasma physics via Dirac’s theory of constrained Hamiltonian systems
We present a Hamiltonian derivation of a class of reduced models in plasma physics obtained by imposing dynamical constraints on a parent Hamiltonian model. We will consider MHD equations and Maxwell-Vlasov equations as parent models. It is shown that the Poisson bracket associated with these reduced models is the Dirac bracket obtained from the Poisson bracket of the parent model.
Nov
16
2011
Mechanics Matters… For Biological Processes on the Nanoscale
A cell is not just a small test tube in which biochemical reactions take place, but it also has a complex and highly dynamic mechanical structure. I will discuss the underlying physical principles that govern cellular mechanics on the nanoscale, and explore how DNA mechanics, on its own and within the context of a heavily crowded, constrained and perpetually fluctuating cellular environment, affects biological function. For example, forces of less than hundred femtonewtons can mechanically switch genes on and off by preventing the formation of regulatory DNA-protein complexes. Special emphasis will be placed on the role of intracellular fluctuations and...
Nov
10
2011
NASA’s Kepler Mission: A Search for Habitable Planets
The Kepler Mission, NASA Discovery mission #10, is specifically designed to survey a portion of our region of the Milky Way galaxy to discover dozens of Earth-size planets in or near the habitable zone and determine how many of the billions of stars in our galaxy have such planets. Results from this mission will allow us to place our solar system within the continuum of planetary systems in the Galaxy.
Nov
10
2011
"Nonlinear and Neural Dynamics in Josephson Networks"
Superconducting Josephson Junctions are one of the most active areas of research in Condensed Matter Physics today.  One unique aspect of Josephson Junctions is the nonlinear relation between the phase of the wave function and the supercurrent flowing though the junction.  This manifests itself in a nonlinear, pendulum-like equation for the dynamics of the phase when the junction is placed in circuit.  Josephson junctions can be fabricated with adjustable parameters, measured in a straightforward fashion, and easily scaled to large network sizes.  In addition, a large Josephson junction circuit measured over a long time contains dynamics...

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