Events Archive

Feb

2012

Gene Regulation by Riboswitches: From Folding Landscape to System Level Description

Feb

2012

Frontiers in Science Public Lecture Featuring Doug Osheroff, Nobel Prize WInner

Doug Osheroff, professor of physics at Stanford University and a Nobel Laureate in Physics, will present a lecture on "How Advances in Science Are Made."

Feb

2012

How Advances in Science Are Made

Feb

2012

Making Realistic Galaxies in Your Computer

Cosmological hydrodynamical simulations are a useful tool for following the formation and evolution of galaxies over long timescales, but we must prescribe accurate models for the physics on small scales, below the resolution limits of our simulations. I investigate several different "subgrid models" at these scales to see what their effects are on a single Milky Way sized galaxy evolved from just after the Big Bang until the present. I grade the success of each model on how well it matches the dynamics of typical disk galaxies, creates a realistic star formation history, and produces a reasonable circumgalactic halo.

Feb

2012

Spin-Nematic Squeezing in a Spin-1 BEC

Squeezed states allow interferometers to surpass the standard quantum limit of the Heisenberg uncertainty principle. Here we study spin-nematic squeezing of a spin-1 condensate following a quench through a nematic-ferromagnetic quantum phase transition. We observe up to -8.3 dB squeezing in the variance of the spin-nematic quadratures. This squeezing is observed for negligible occupation of the squeezed modes and is analogous to optical two-mode vacuum squeezing [1]. 1. C.D. Hamley, C.D. Gerving, T.M. Hoang, E.M. Bookjans, and M.S. Chapman, “Spin-Nematic Squeezed Vacuum in a Quantum Gas,” To appear in Nature...

Feb

2012

Multiscale studies of cadherin-mediated cell adhesion

Cadherins constitute a large family of Ca2+-dependent adhesion molecules in the Inter-cellular junctions that play a pivotal role in the assembly of cells into specific three-dimensional tissues. Although the molecular mechanisms underlying cadherin-mediated cell adhesion are still not fully understood, it seems likely that both cis dimers that are formed by binding of extracellular domains of two cadherins on the same cell surface, and trans-dimers formed between cadherins on opposing cell surfaces, are critical to trigger the junction formation. Here we present a new multiscale computational strategy to model the process of junction formation...

Feb

2012

Effective Field Theory and Ultracold Atoms

The development of the technology for trapping atoms in the vacuum and cooling them to ultralow temperatures has opened up the exciting new field of cold atom physics. This field provides a new domain of applications for local quantum field theory, an approach whose previous applications have been primarily in high energy particle physics and have involved energy scales that are more than 20 orders of magnitude higher. I will describe a systematic approximation method for quantum field theory called Effective Field Theory that has proved to be a powerful framework for addressing many important problems in ultracold atoms.

Feb

2012

Three-dimensional Analysis of Clathrin-mediated Membrane Trafficking in Living Cells

Jan

2012

Ion and nanodrop injection from Taylor cones into gases and liquids

Jan

2012

Formulate Biological Sensory Adaptation