Friday, July 18, 2014

Science Friday: The End of Gamow

Finally finished this classic of popular physics I've had since the 80s, George Gamow's classic, Thirty Years That Shook Physics.

The previous posts were:

1a. Planck's Quantum
1b. Jumping Photons (Einstein and the Photoelectric Effect)
1c. The Compton Effect (Proof of Energy Packets)

2a. Thomson and Rutherford's Atoms
2b. Bohr's Contributions (How electrons fill the atom)

3a. Pauli Exclusion Principle (no two electrons at any one energy state)
3b. The Pauli Neutrino

4a. De Broglie's Wavy Particles
4b. Schrödinger's Wave Equation

5. Heisenberg's Uncertainty Principle
6. Dirac's Anti-Particles
7. Chapters 7-8: Fermi and Yukawa

And now the final chapter, "Men and Work" and the playful stunt play, "The Blegdmasvej Faust"

1. Gamow was writing in the 1960s and, from his perspective, not much momentous had taken place in the some thirty years since the content of the book. To be sure, we have seen the perfection of the Standard Model with numerous particles not mentioned in Gamow's books (e.g., quarks). But as Lee Smolin's book, The Trouble with Physics, reflects, the breakthrough that Gamow hoped would take place before the year 2000 is yet to happen. [As an addendum, see this post of mine.]

Not only has Gamow sat on my shelves for years, there are a number of "physics classics" there waiting to be read in this series, QED, The First Three Minutes, A Brief History of Time. All in good time. But I think I'm going to go next to a biography of Richard Feynman. If Einstein typified 1900-1920, if Bohr dominated 1920-1940, Feynman is the central figure of quantum physics in the mid-twentieth century, it seems to me. So next Friday I hope to post on the first chapter of Quantum Man.

2. Gamow, I think, gives some great insights in this final chapter. He suggests that one path forward might be to explore the significance of a new set of fundamental "dimensions" in the quantum world. In the large world we inhabit, length, time, and mass are the key dimensions from which all other physical quantities and units are derived.

But what if there are really much more fundamental units when we get right down to the bottom line of existence at the quantum level. It's not hard to figure out what the first two of the three most fundamental constants might be. Planck stumbled on one--h or Planck's constant. It seems to pop up all over the place in the atomic world. The speed of light, c, is another, the dandy of Einstein.

But what might the third be? Gamow suggests that there might be a fundamental unit of distance, λ, anticipated from Pythagoras to Heisenberg. He suggests it is somewhere around 2.8 x 10-13cm, the range of forces acting between nucleons and the point at which all the calculations seem to go to infinity. I don't know whether this specific suggestion ever went anywhere, although I do believe the notion that there is a quantum distance of this sort is quite commonly held (e.g., a Planck length).

2. He ends with an informal play performed in 1932 in Copenhagen, a riff off the German play Faust, in which a genius is bored with all normal learning and sells his soul to the Devil. Gamow was prevented from attending because the Soviet's wouldn't let him go from Russia at that time.

Faust itself is rather sacrilegious, so it might be a bit jarring. God stands for Bohr in the play, and Pauli is the Devil (Mephisto). God is pleaing for Mephisto not to take away all of his prized notions, like mass and charge. All the Devil is interested in is the neutrino.

Probably the best known part of the play is Faust's opening monologue and it's fun to see what they've done with it. "I have--alas--learned Valence Chemistry... Yet here I stand, for all my lore, No wiser than I was before..."

The play seems to jump from image to image. No doubt those at the conference found much of it hilarious (such as things falling into Dirac's holes). Mephisto (Pauli) longs for his neutrino (Gretchen) but, in the end, Chadwick's neutron is what shows up.


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