Tuesday, June 5, 2018

Books reviewed: TIM MAUDLIN - The Defeat of Reason

What Is Real?: The Unfinished Quest for the Meaning of Quantum Physics - by Adam Becker
The Ashtray: (Or the Man Who Denied Reality) - by Errol Morris
Reviewed by TIM MAUDLIN

...this book could prove to be a watershed moment for the physics community if it faces up to its own past and its present. Or, following the fate of Einstein, Bohm, and Everett, Becker could just be ignored. But if you have any interest in the implications of quantum theory, or in the suppression of scientific curiosity, What is Real? is required reading. There is no more reliable, careful, and readable account of the whole history of quantum theory in all its scandalous detail...

....In the conventional story, Einstein, once the radical, has aged into a conservative who cannot abide the idea that God plays dice. Desperate for determinism, he challenges Bohr with a thought experiment designed to show the untenability of Bohr’s contention that you cannot do better—even in principle—than probabilistic predictions. The necessity of probabilism was encoded in the Heisenberg uncertainty relations, which assert that the better one can predict one aspect of a system (e.g., its position), the worse one can predict another (e.g., its momentum). Einstein’s thought experiment comes as a shock, but after a tense night Bohr hits on the solution and refutes Einstein with his own brainchild: the general theory of relativity. A showdown for the ages. Einstein, defeated, drifts into crankhood, never more doing significant physics....

Here Becker begins his exposé. He shows that every single detail of the standard account of the Solvay Conference is untrue. Einstein was not concerned with saving determinism. His example was not designed to refute the uncertainty relation. And most critically, Bohr did not win, he lost. Thus begins the great debunking. None of this is news to historians and philosophers of physics. The true account has been worked out by many people whom Becker cites. But he has done prodigious research and created a powerful narrative....

People are gullible. Humans can be duped by liars and conned by frauds; manipulated by rhetoric and beguiled by self-regard; browbeaten, cajoled, seduced, intimidated, flattered, wheedled, inveigled, and ensnared. In this respect, humans are unique in the animal kingdom. Aristotle emphasizes another characteristic. Humans alone, he tells us, have logos: reason. Man, according to the Stoics, is zoön logikon, the reasoning animal. But on reflection, the first set of characteristics arises from the second. It is only because we reason and think and use language that we can be hoodwinked.

Not only can people be led astray, most people are. If the devout Christian is right, then committed Hindus and Jews and Buddhists and atheists are wrong. When so many groups disagree, the majority must be mistaken. And if the majority is misguided on just this one topic, then almost everyone must be mistaken on some issues of great importance. This is a hard lesson to learn, because it is paradoxical to accept one’s own folly. You cannot at the same time believe something and recognize that you are a mug to believe it. If you sincerely judge that it is raining outside, you cannot at the same time be convinced that you are mistaken in your belief. A sucker may be born every minute, but somehow that sucker is never oneself.

The two books under consideration here bring the paradox home, each in its own way. Adam Becker’s What Is Real? chronicles the tragic side of a crowning achievement of reason, quantum physics. The documentarian Errol Morris gives us The Ashtray, a semi-autobiographical tale of the supremely influential The Structure of Scientific Revolutions (1962) by Thomas S. Kuhn. Both are spellbinding intellectual adventures into the limits, fragility, and infirmity of human reason. Becker covers the sweep of history, from the 1925 birth of the “new” quantum physics up through the present day. Morris’s tale is more picaresque. Anecdotes, cameos, interviews, historical digressions, sly sidenotes, and striking illustrations hang off a central spine that recounts critical episodes in the history of analytic philosophy.

Quantum theory first. Becker does not discuss the earliest signs that something was amiss in the theory of light and matter, but the fundamentals are well known. The first hints of particle-like behavior in electromagnetic waves were dropped by Max Planck in his treatment of blackbody radiation, the light given off as a body heats up. In 1905 Albert Einstein took a decisive step with his analysis of the photoelectric effect, the current that flows in certain metals exposed to light. Einstein postulated that the light wave delivers its energy to the metal in small packets or quanta. The energy per packet varies with the color (frequency) of the light, and the number of packets with the brightness (amplitude). Below a critical frequency, no current flows, no matter how bright the light. Above that frequency, some flows no matter how dim.

Light is not just absorbed by matter; it is also emitted. The emission from atoms occurs at only certain precise frequencies. These constitute atomic spectra, which permit us to determine how much of each element there is in a distant star. In 1913 Niels Bohr devised the Bohr atom. Electrons orbit the nucleus just like planets orbiting the sun. Only certain orbits - which Bohr gave rules for - are available to the electron, and when an electron jumps from a higher orbit to a lower one, it emits light of a frequency determined by the energies of the orbits. The challenge was figuring out how these quantum jumps happen. Over the next decade, Bohr failed to find any precise electron motions. 

The spectra and intensities of emitted light never came out right. This is the period of the “old” quantum theory. Becker’s main historical narrative begins dramatically at the October 1927 Fifth Solvay International Conference in Brussels… read more: