Society of Physics Students

hbar@phys.columbia.edu

Columbia University in the City of New York

Spring 2005

 April 14, 2005

Speaker: Jacob Aaron Barandes, Graduate Student in Physics, Harvard University

Talk Title: Anticommuting Numbers

Abstract:

Anticommuting (or Grassman) numbers play a very important role in physics, although their nature can seem somewhat abstract. Their importance can be seen upon attempting to obtain relativistic quantum theories for half-integer-spin particles, called fermions, like electrons and quarks. In this talk, I will give a qualitative discussion of why anticommuting numbers are absolutely necessary to maintain causality and to yield stable field theories for fermions. I will discuss the famous spin-statistics connection, and then spend the rest of the talk laying out the rules for handling anticommuting numbers, including formal notions of differentiation and integration. A copy of the write-up for this talk can be found here.

 March 4, 2005

Speaker: Yuhai Tu, Physical Sciences & Computational Biology Center IBM T. J. Watson Research Center

Talk Title: Some Random Thoughts at the Boundary of Physics and Biology

Abstract:

Some general analogies between research in morden biology and physics will be made first. The main part of the talk will be focused on describing some recent works in understanding bacterial chemotaxis (bacteria's sense of smell) to illustrate the importance of physics in understanding complex biological systems.

 February 3, 2005

Speaker: Bill Goff, Head of Quantitative Research at Sanno Point Capital Managment, NY

Talk Title: Brownian Motion: From Physics to Finance

Abstract:

I will talk informally about my careers in physics and finance and describe several of the areas that I have worked on.