Particles Aren’t Particles and Other Surprises
Quantum theory is difficult to understand, but Art Hobson's book is an unusually clear take on the subject for people outside the quantum physics field.
Like many consumers of scientific books, I read them for fun. Understanding our place in larger systems is interesting and scratches the ever-present “meaning of life” itch.
It’s also a great excuse for not understanding how quantum physics works.
Anyone who’s tried to break into this topic runs into a difficult vocabulary test on top of the new rules physics follows in the quantum realm. Art Hobson begins Tales of the Quantum by comparing quantum rules to classical physics’ rules:
“Before 1900, scientists thought identical conditions led to identical results. Well, they don’t. Nature contradicts this plausible principle predicted by “classical physics” throughout the period 1650 to 1900, according to which the universe is precisely predictable the way an accurate clock is predictable. But nature is not like a clock. Nature herself doesn’t know the future as she actively creates what happens at every instant to every quantum of the universe.”
Even the parts of this book that dive into the technicalities of quantum theory are this approachable. It’s a rare quality for a quantum physics book.
What “Nothing" Really Is
Every movie about space invokes the “vacuum of space” to remind the audience how empty and frightening space is. The emptiness is terrifying, but physicists have a more nuanced view of the vacuum of space:
“But surprisingly, in modern physics, the word vacuum no longer means nothingness,” Hobson wrote. “In modern physics, a physical vacuum means a region devoid of all quanta, but this does not amount to nothingness. In fact, every quantum is simply a wave, or disturbance, within physically real vacuum fields that contain energy and are not “nothing.”
Quantum fields are a vital piece of Hobson’s explanation of quantum physics. Many people probably have the same model in their heads of particles they learned in middle school. However, quantum physics isn’t about balls bouncing around the universe. Instead, it’s about ripples in fields that behave more like water than balls. As he approaches the book’s halfway mark, Hobson advises:
“There are no particles. Do not imagine, when visualizing a photon or electron as a ripple in a field, that there is a tiny particle floating within the ripple. The ripple is the photon or election. Fields are all there is.”
This book was published in 2017, the same year I graduated college. Imagine how irritated I was to have the wrong physics model in my head every time I tried to crack into this dense topic. It also made trying to understand quantum theory easier and made the paradoxical experiments make more sense.
Under the Surface of Quantum Mechanics
I could only scratch the surface of quantum mechanics. Hobsen’s book is a great introduction to the subject and clarifying for anyone who tries to navigate those mysteries for themselves. I’ll leave you off with one of the book’s most profound paragraphs:
“An empty universe is inconsistent with the quantum rules. A spatially extended universe must, at a minimum, be entirely filled with vacuum quantum fields, because true emptiness would violate Heisenberg’s principle. This obviously doesn’t entirely answer the philosopher’s question as to why there is something rather than nothing, but perhaps it’s part of the answer.”
You may be surprised to learn that this passage is only a little past the book's halfway mark. Once Hobson introduces the concept of fields instead of individual particles, he unleashes a new way to view the universe that science readers will find enjoyable.
I can’t promise that Hobson will make quantum mechanics easy. There’s no getting out of the study required to wrap your head around even superficial parts of those theories. But if you’re interested in how quantum fields, Heisenberg’s principle, and the universe’s existence come together, this is an insightful read.