By Chet Yarbrough
Narrated by Kent Cassella
The book cover of “For the Love of Physics” summarizes its endearing intent; i.e. an illustration of joy in physics. Walter Lewin bridges the chasm between the lay public and Physics by simplifying and vivifying fundamental laws of a confusing science. With erudition and demonstration Lewin reflects joy in physics. Lewin is a teacher and astrophysicist at the Massachusetts Institute of Technology.
Warren Goldstein’s introduction to the book profiles Lewin as a beloved professor of Physics that delights his students with concrete demonstrations of Newton’s laws, Maxwell’s theory of electromagnetism, and Einstein’s quest for a unified field theory.
Goldstein’s characterization of Lewin makes one wish they were at the beginning of their college career; maybe not as a physicist but as a student of a professor that knows how to teach their subject with joy, erudition, and clarity.
This book is semi-autobiographical. With due respect to Lewin’s life history, “…the Love of Physics” importantly reveals some of the fundamentals of physics in a way that is both interesting and clear (at least, relatively clear) to the scientifically illiterate.
In the first chapter of the book, the critical importance of accurate measurement is defined. Scientific knowledge is a function of accurate measurement but measurement is only correct within a range defined as probability in quantum mechanics. The advance of quantum mechanics means that nothing in the world is perfectly reproducible in an experimental context; i.e. every quantifiable result is defined by probability rather than certainty. The irony is that all correct scientific advances are founded on experimental verification of results by a quantitative measurement; however, that measurement is always, plus or minus, a degree of accuracy.
Lewin admires the concept of “string theory” but is skeptical of any claim that it is near a proof of “the theory of everything”; i.e. the elusive unified field theory that Einstein failed to find in the course of his remarkable life. String theorists suggest that small strings are fundamental elements of everything in the universe and that string vibration determines elemental character. A string is surmised to be a building block of all elements in the universe; i.e. if string theory is true, turning lead into gold may be a matter of knowing how to pluck the string.
The idea of strings, smaller than a Planck length, might be correct but until strings can be measured it remains a theory. Because a Planck length cannot be measured in today’s science, one wonders how far probability calculations are from the measure and confirmation of strings.
Lewin considers Newton, Maxwell, and Einstein to be the greatest scientists in history because of their prescient ability to produce theories that unify laws of nature. Though quantum mechanics was never fully accepted by Einstein and not discovered until Newton and James Clerk Maxwell were gone, these three scientists viewed the world with blunt measurement tools and changed human’ knowledge of the world. Ironically, they succeeded in creating theories that have been confirmed by future physicists using quantum mechanics to confirm their hypothesis.
Science continues to advance with refinement of particle physics cyclotrons like the Large Hadron Collider that are exploding protons into constituent elements and refined tools that measure smaller and smaller elemental particles that define bigger and bigger natural laws.
Lewin and Goldstein’s book excites the imagination and encourages the future of science.