Living with Uncertainty

Chapter 2 from A Different Universe by Robert Laughlin.

Biologists and physicists:

… most biologists consider the physicists’ obsession with certainty and correctness to be exasperatingly childish and evidence of their limited mental capacities. Physicists, in contrast, consider tolerance of uncertainty to be an excuse for second-rate experimentation and a potential source of false claim.

Importance of measurement in physics:

The impulse to measure things accurately is the same as the impulse to make do-it-yourself repairs.

It is why buildings and academic majors at the Massachusetts Institute of Technology have numbers rather than names. Accurate measurement is simply natural behavior for people who see nothing strange in creating building ten, building thirteen, and course eight.

Physical scientists, on the other hand, tend to see the matter morally. They orient their lives around the assumption that the world is precise and orderly, and that its occasional failure to conform to this vision is a misperception brought about by their not having measured sufficiently accurately or thought sufficiently carefully about the results.

My brother-in-law the divorce atterney says that his most exasperating clients are Silicon Valley engineers, who typically want to just write down the family assets, divide them equally, shake hands, and be done with it.

Universal physical quantities:

Paradoxically, the existence of these highly reproducible experiments leads us to think in two mutually incompatible ways about what is fundamental. One is that exactness reveals something about the primitive buildings blocks out of which our complicated, uncertain world is made. … The other is that exactness is a collective effect that comes into existence because of a principle of organization.

A much more immediate and troubling case of collectivism is the determination of the electron charge and Planck’s constant by means of macroscopic measurements. … Both are highly reductionist concepts, and both are traditionally determined using huge machines that measure properties of individual electrons ripped off of atoms. But their most accurate determination turns out to come not from these machines at all but simply from combining the Josephson and von Klitzing constants, the measurement of which requires nothing more sophisticated than a cryogenic refrigerator and a voltmeter.

But the electron charge is another matter. We are accustomed to thinking of this charge as a building block of nature requiring no collective context to make sense. The experiment in question, of course refute this idea. They reveal that the electron charge makes sense only in a collective context …