This short (88 pages) easily readable book expands on a series of articles originally written as Sunday supplements for the Italian newspaper, Il Sole 24 Ore. Each article (lesson) is devoted to one major topic in modern physics – General Relativity, quantum theory, cosmology, sub-atomic particles, the nature of space, probability and time, and finally, “ourselves.” They are intended for those “who know little or nothing about modern science.” Rovelli does a nice job of putting the nuggets of the big ideas in physics and cosmology into layman’s language. In practice, the big ideas are woven into large, intricate, quantitative, theories, the details of which are well beyond the grasp of non-physicists like me. The book succeeds by not trying to do too much. Rovelli extracts a core principle from each topic, describes it simply, and does his best to help us come to terms with its strangeness. We are not going to understand these principles in the way that we understand events in daily life. Advanced physics isn’t going to make sense in any intuitive, gut level way because it deals with entities and concepts that we can’t experience and that have properties and take part in interactions that we can’t truly envision. (During an interview with a reporter who asked him to explain a difficult physics concept in terms that he, the reporter, could understand, the physicist, Richard Feynman replied, “In terms that you understand, I don’t understand it.”) Our perceptions are inadequate, our everyday language too impoverished to do the job, and learning “physics-ese” takes many years of study and mastering heavy-duty mathematics. But the loose analogies and images that Rovelli uses shows how to think about space, time, the sub-atomic world, etc., and maybe more importantly, to feel comfortable with not grasping them more intimately.
The first four lessons draw from the essential foundations of modern physics and cosmology; they cover the meat of the subjects that we should all know about. The next two include heavy doses of speculation about the granularity of space and time – they are fascinating, but newer and even more abstract than the first four. Close to the border of physics and philosophy, they sketch out the kinds of ultra-deep questions confronting physics today. The final lesson is frankly philosophical; venturing beyond the confines of physics to consider related advances in other fields. Rosselli knows how impossible it is to say anything meaningful about, for example, particle physics and human consciousness in the same chapter, yet he feels obligated to try. and manages a few interesting thoughts along the way.
In summary, Rovelli provides a good introduction or refresher for some of the biggest ideas in science. And, although it is not his main objective, he imparts a good deal of wisdom concerning science and scientific thinking in general, which fans of the scientific hypothesis will find valuable. I recommend Seven Brief Lessons on Physics by Carlo Rovelli, and thank Gerard Kiernan telling me about it.
Seven Brief Lessons on Physics, by Carlo Rovelli (translated by Simon Carnell and Erica Segre), New York: Riverhead Books; 2016).