Tag Archives: Quantum Field Theory

Book: Einstein’s Cosmos

Einstein's Cosmos by Michio Kaku

Excellent modern physics primer that’s mostly a biography of Einstein
203 pages, ★★★★

Author Michio Kaku is a very talented science writer. He is one of the few science writers who achieves the near-impossible goal of communicating advanced science accurately, in a way that’s easy to understand, and with added humour throughout. Most writers can’t do that!

In Einstein’s Cosmos, Kaku explores how Einstein’s life story shaped almost all of modern physics. The question of uniting two seemingly incompatible theories is a recurring theme in this book (and in physics itself). The first instance is on page 11, where we learn how Einstein was faced with the problem of reconciling Newton’s forces and Maxwell’s fields. “One of them had to fall”, Kaku writes. Einstein would topple Newtonian forces and replace them with something beautifully simple.

Kaku’s analogies are very easy to understand. To illustrate length contractions and time dilations using cars, he slows the speed of light down to 20mph and describes what each observer would see.

We’re now faced with an incompatibility between general relativity and quantum field theory. Both hold true at different scales, but they don’t seem to overlap properly as part of a grand “unifying theory”. Just as Einstein unified Newton’s and Maxwell’s equations, physicists are now faced with the task of unifying general relativity and quantum field theory—and the book almost exactly as it started.

Beautiful! ★★★★

 

Book: Quantum Theory: A Very Short Introduction

I’m feeling a lull after reading Haruki Murakami’s epic 1Q84. I even considered giving in to star-inflation and giving it a six- or seven-star rating. 1Q84 changed my taste in books.

I’ve also run out of books. 1Q84 raised the bar for me so drastically that yesterday, for the first time ever, I returned home from the library empty-handed. That Chinese children’s book aside, nothing on the shelves appealed to me. Only 8 books in the library’s database had the caliber to match Haruki Murakami’s 1Q84 (most of which are novels by J.K. Rowling, Haruki Murakami and Mo Yan), and none of them were available. I’m roughly third in the queue for each of them, so about a two-month wait is expected.

So I hunted for books on my iPod. Like most digitally-pirated books, I found they were all quite boring, too (it’s interesting how the pirate internet contains only the most popular music but only the least popular books). This book on Quantum Theory was the best of a terrible selection.

So here goes…

Quantum Theory
Another PDF on iBooks

If I were ever forced to learn quantum theory, I’d start by reading this book.
128 pages, ★★★

Neither entertaining nor comprehensive, this book is exactly what its title promises: a very short introduction.

Written by the highly-respected John Polkinghorne, this book introduces a world where the laws of nature are so far-removed from that of our everyday experience that they are practically incomprehensible to most laypeople. Feynman said, “we can safely say that nobody understands Quantum Theory”. Someone else famous said, “If a person claims to understand quantum theory, then they are lying”.

I didn’t enjoy reading this book, and I’d only recommend it for those who, for whatever unthinkable reason, are required to know the basics of quantum theory (perhaps for a one-off job or for a test). Only in this rare and unfortunate circumstance would I recommend this book to anyone sane. I give it stars because it’s a well-written (if dry), and if you push yourself, you can learn something. I hold back two stars because this book want as fun as it could’ve been. A Very Short Introduction to Relativity might be more interesting. ★★★

1Q84 refined my taste in books. You’ll see more famous fiction reviewed on this blog in the future. I promise.

Book: The Trouble with Physics

The Trouble With Physics The Rise of String Theory, The Fall of a Science, and What Comes Next
Available in black, magnolia, blue or an elegantly redesigned white edition.

An inconclusive book on an inconclusive subject.
416 pages, ★

Physics is dead. Or maybe it’s just finished. According to the Trouble with Physics, no significant progress has been made towards a ‘grand unifying theory’ since the 1980s. Unfortunately, that was when the author started his physics career.

Theories are developed that fit the available evidence at the time. According to Popper, “a theory is only good until it’s falsified”, and according to Einstein, “a theory should be as simple as it can possibly be, but no simpler”. Theories thus tend to be simple (at least in retrospect) and short-lived.

The trouble with physics comes with the most recent theory, String Theory. It’s neither simple nor short-lived. In fact, it’s so complicated that most physicists don’t fully understand it (or that’s what they claim), and because it can never be proven or disproven, it is effectively permanent. Author Lee Smolin talks about the quasi-religious following surrounding String Theory and its excessive derision of critics. To me, the String Theory lobby sounds about as entrenched as that of climate change, or of intelligent design. If that’s the case, then physics is definitely finished.

As a newcomer to physics, I learned a lot of theory from this book. I learned about General Relativity, Quantum Theory, Loop Quantum Gravity, Technicolor, Twistor Theory and MSSM theory; and the discoveries made by Aristotle, Kepler, Galileo, de Sitter, Einstein, Kelvin, Eddington, Popper and many, many more. Despite the level of detail in this book, math is used only sparingly—which is why I chose this book over others.

The Trouble With Physics is suitable for non-physicists who want to reassure themselves that they made the right career choice. In just 416 pages, The Trouble with Physics provides enough background information to understand passing conversations with physicists, and to understand almost all Big Bang Theory jokes. This book is the most readable in its category.