Friday, August 23, 2019

Basic questions about condensed matter

I am trying out draft chapters of Condensed matter physics: A very short introduction, on a few people who I see as representative of my target audience. My son is an economist but has not studied science beyond high school. He enjoys reading widely. He kindly agreed to give me feedback on each draft chapter. Last week he read the first two chapters and his feedback was extremely helpful. He asked me several excellent questions that he thought I should answer.

1. What do you think is the coolest or most exciting thing that CMP has discovered? explained?

2. Scientific knowledge changes with time. Sometimes long-accepted ``facts''  and ``theories'' become overturned? What ideas and results are you presenting that you are almost absolutely certain of? What might be overturned?

3. What are the most interesting historical anecdotes? What are the most significant historical events? Who were the major players?

4. What are the sexy questions that CMP might answer in the foreseeable future?

I have some preliminary answers. But, to avoid prejudicing some brainstorming, I will post later.
What answers would you give?


  1. 1. BCS superconductivity and the quantum hall effect(s).

    3. Major players: the first to come to my mind would be Landau, Bardeen and perhaps (as an educator primarily) Sommerfeld.

  2. (1a) Classical condensed matter physics: Entropic transitions in hard-core systems
    (1b) Quantum condensed matter physics: The Quantum Hall Effects
    (2) I'm sure of the whole edifice of statistical physics and thermodynamics as applied to condensed matter physics systems that can be thought of in classical terms. I am less sure of issues involving decoherence and the quantum-to-classical crossover.
    (3) Major players: Anderson, de Gennes, Landau, Kohn, Landau, Bardeen. Historical events: The BCS paper, the gang-of-four paper, the Kosterlitz-Thouless paper, possibly the foundational papers on topological insulators
    (4) Room temperature superconductivity, the "right" theory of high-Tc

    1. Hi Gautam,
      Could you expand on 1a or give me a seminal reference?

    2. Asakura, Sho; Oosawa,F (1 January 1954). "On Interaction between Two Bodies Immersed in a Solution of Macromolecules". The Journal of Chemical Physics. 22 (7): 1255 would be one classic reference. Another is: B. J. Alder and T. E. Wainwright (1957). "Phase Transition for a Hard Sphere System". J. Chem. Phys. 27 (5): 1208

  3. (1,3) We take it for granted today, but the usefulness of band structures in describing the electronic properties of any crystalline material never ceases to amaze me.

  4. Thanks for the very helpful comments and suggestions. I welcome more. The next post will give some of my preliminary answers.

  5. How could I forget my own personal hero: Ken Wilson!