I am beginning “A Different Universe’ by Robert Laughlin and I expect to have much to say. In Chapter 2 he compares physicists with biologists by noting that physicists like exact results where biologists don’t expect such. Physics, at least classical physics has very successful theories that make successful predictions over many orders of magnitude. Biologists don’t. This seems to me to be the root of this difference. (Particle physicists don’t have laws that work over many orders of magnitude either.)

Minor quibble: On page 30 he claims that sensitivity to initial positions of the atoms in a (classical) gas effectively makes the gas non-deterministic on the atomic scale, and in turn that leads to the chaos that precludes weather prediction. I think he skips a level here; quantitative turbulence does not depend on Avagodro’s number, I think, and neither, thus, does chaos. Turbulence is the bane of weather prediction. In a sense this quibble even strengthens his arguments. (This needs cleaning!) Hydrodynamics takes no note of Avagadro’s number yet leads to turbulence (a form of chaos) since the differential equations of hydrodynamics lack unique solutions, indeed lack any differentiable solutions. The differential can be replaced by more liberal integral equations that allow fractal solutions which model turbulence. We do not know how to compute these very well. None of this depends on atomic theory.

On page 31 he says of quantum theory: “rules so different from Newton’s that scientists struggled to find proper words to describe them.”. I would say “struggled and failed”. Equations, yes; words, no. This was indeed a theme of a short scene in the recent movie, “A Reasonable Man”.

At the top of page 36 he finally says: “microscopic laws are true and could plausibly cause phases; therefore we are sure they do cause them, even though we cannot prove this deductively.”. Considering how difficult it is to compute the spectrum of helium from Schrödinger’s equation, without making very gross approximations, it is not surprising that phase calculations are totally infeasible. With Feynman’s dictum we are thus in a position of generating new theories for phases every bit as fundamental as Schrödinger’s!

At the end of page 52 Laughlin says of quantum entanglement: “Nonetheless it is true. The simplest and most direct of the many experiments verifying its validity is atomic spectroscopy. Atomic vapors emit very specific wavelengths of light, whose exact values depend on the atom but whose sharpness and distinctiveness do not. The wavelengths are accounted for with enormous accuracy by the rules of motion of entangled electron wave functions. …”. Laughlin clearly knows much more QM than I but the last time I did a web search the closest thing that I could find to an ab initio calculation of the helium spectrum was a paper describing how such a calculation could be organized, and not a report of such a calculation. I must search again! See below.

Calling the two s=1 electrons of a Lithium atom “closed shell” is no excuse for the crude approximation suggested here. The concepts of ‘closed shell’ and ‘shielding’ are something to be derived from Schrödinger’s equation, not as adjunct to Schrödinger’s equation to facilitate calculation.

I think that Chapter 11 can be summed up as distinguishing the methods of chemists from the methods of physicists, and then concluding that neither is competent to address mesoscale phenomena to which the both aspire. At least that is the part that I find plausible.

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