Publisher: Basic Books
Publication date: 1/29/2013
How would a citizen scientist go about the task of learning about the universe? What basic knowledge is requisite for the study of quantum mechanics? Why would an average person want to wrap her head around equations that stumped Newton, Faraday or Einstein?
Stanford University physics professor Leonard Susskind lays out a learning plan in his new book, The Theoretical Minimum: What You Need to Know to Start Doing Physics.
Celebrated for his work on string theory, black holes and the origins of massive particles, Susskind co-wrote the book with George Hrabovsky, an amateur theoretical physicist and student of his series of lectures on physics. Now available online at Stanford University’s YouTube Channel, the lectures became the basis for the book after Hrabovsky suggested the idea in an email.
Susskind first set out to make physics accessible to a general audience by teaching an introductory physics course through Stanford’s Continuing Studies program.
“These students were there for only one reason: Not to get credit, not to get a degree and not to be tested, but just to learn and indulge their curiosity.”
According to Susskind, he found it more than satisfying to teach the course, which exhibited “a lively vibrancy that academic classes often lack.”
Susskind’s lectures became an alternative to the conventional college class. He found that people were intensely eager to learn physics and writes, “They were ready to try their hand at learning the real thing—with equations.”
In the book, Susskind introduces Newton’s equations for the motion of particles, the Maxwell-Faraday theory of electromagnetic fields and Einstein’s general theory of relativity in more or less an iconic way: “Imagine…”
The Theoretical Minimum differs from popular science and textbook physics, if your inner mathematician can stomach the trigonometry, and offers the most salient material so learners can proceed to the next level: quantum mechanics.
The book certainly helps newbies appreciate the beauty and efficiency of classical physics, but the nonacademic voice of Hrabovsky seems somewhat dimmed by Susskind’s instructional equations. A coherent synthesis from Hrabovsky might have improved an apprentice’s understanding.
More curious learners will find an appendix on central forces and planetary orbits at the back of book. Additional material can be found online, including a downloadable overview of mathematical logic and proof at www.madscitech.org/tm.
The eureka moments happen if you persist through the more knotty lectures, especially one on energy and the case of a single particle moving along an x axis under the influence of a force. Here, Susskind introduces the principle of least action. Essentially, “The universe is lazy.”
“This simple rule (it can be written in a single line) summarizes everything! Not only the principles of classical mechanics, but electromagnetism, general relativity, quantum mechanics, everything known about chemistry—right down to the ultimate known constituents of matter, elementary particles.”
Susskind writes that an orbit (or trajectory) minimizes the action of stroboscopic points along that x axis and packages everything about a system in a concise function, the Lagrangian (L).
What? Bear with me… I have yet to untangle the difference between a function and an equation!
The Theoretical Minimum by Leonard Susskind and George Hrabovsky is a worthwhile read for anyone wanting to learn the foundations of classical physics and advance to quantum mechanics.
Category: Nonfiction, Physics