Thursday, March 16, 2017

Introducing students to John Bardeen

At UQ there is a great student physics club, PAIN. Their weekly meeting is called the "error bar." This friday they are having a session on the history of physics and asked faculty if any would talk "about interesting stories or anecdotes about people, discoveries, and ideas relating to physics."

I thought for a while and decided on John Bardeen. There is a lot I find interesting. He is the only person to receive two Nobel Prizes in Physics. Arguably, the discovery associated with both prizes (transistor, BCS theory) are of greater significance than the average Nobel. The difficult relationship with Shockley, who in some sense became the founder of Silicon Valley.

Here are my slides.


In preparing the talk I read the interesting articles in the April 1992 issue of Physics Today that was completely dedicated to Bardeen. In his article David Pines, says
[Bardeen's] approach to scientific problems went something like this: 
  • Focus first on the experimental results, by careful reading of the literature and personal contact with members of leading experimental groups. 
  • Develop a phenomenological description that ties the key experimental facts together. 
  • Avoid bringing along prior theoretical baggage, and do not insist that a phenomenological description map onto a particular theoretical model. Explore alternative physical pictures and mathematical descriptions without becoming wedded to a specific theoretical approach. 
  • Use thermodynamic and macroscopic arguments before proceeding to microscopic calculations. 
  • Focus on physical understanding, not mathematical elegance. Use the simplest possible mathematical descriptions. 
  • Keep up with new developments and techniques in theory, for one of these could prove useful for the problem at hand. 
  • Don't give up! Stay with the problem until it's solved. 
In summary, John believed in a bottom-up, experimentally based approach to doing physics, as distinguished from a top-down, model-driven approach. To put it another way, deciding on an appropriate model Hamiltonian was John's penultimate step in solving a problem, not his first.
With regard to "interesting stories or anecdotes about people, discoveries, and ideas relating to physics," what would you talk about?

3 comments:

  1. It's a bit on the darker side of physics, but I've long been fascinated by the Schon scandal. I highly recommend the book "Plastic Fantastic" if you haven't already read it.

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    Replies
    1. I agree this is a good topic. After the scandal I did have a talk I used a couple of times. In todays climate it is particularly relevant because of the issues of the role of luxury journals, senior authors who take credit but not liability, ...

      I have not read the book. I am not game to. I think I would just get too angry and depressed...

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  2. "To put it another way, deciding on an appropriate model Hamiltonian was John's penultimate step in solving a problem, not his first."

    A refreshing thought in the current climate...!

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