It felt nice finally reading a book about physics written in a way even I can half-understand. Back in 2003 or 2004, I heard about Brian Green’s “The Elegant Universe”, and ever since then I’ve been curious about the string theory and all those extra dimensions hidden in the curvature of space-time, but I never got a chance to read the book or even watch the video.
Then an extended version of Stephen Hawking’s “A Brief History of Time” fell into my hands and I thought: even better. Stephen Hawking is definitely THE brain of the century, so I started reading, and I read the book with gusto.
The history of scientific discoveries
I like how Mr. Hawking made this summary of the history of physics and discoveries about the universe interesting and well-organized. He starts with the millenia-old assumption that our world is a flat disc resting on the shoulders of a turtle (or tortoise, as he says – pardonne-moi, tortoises!), and in-between he wittily, eloquently recounts how we progressed from thinking our world is on top of a giant turtle, to knowing that we orbit the Sun that orbits the center of the galaxy, which is, probably, a super massive black hole.
Mr. Hawking starts with how Aristotle realized that the Earth was round by watching the Earth’s shadow on the moon. It was round, and that was possible only if the Earth was round as well. By that time, other Greeks knew something was fishy about the “flat disc” theory as well, because they watched the ships come from afar and noticed that the sail of the ship always appeared first, and then the lower part.
Then comes the story about the Ptolomy’s cosmological model where Earth is in the center, followed by Copernicus’, Kepler’s and Galileo’s convictions that the Earth orbits the Sun (the theory for which men were burned at the time), followed by one of the most amazing discoveries in science by Newton – the gravity, followed by many other timelines and contributions by students of astronomy.
Don’t understand? Read on.
That narrative part of the book I understood well. What I understood a bit less, and when I say “a bit”, I mean “a lot”, were the more detailed explanations of certain theories and laws. For example, I have trouble understanding one of the core concepts of the book (and physics) – infinite mass. That’s just one example.
But I wouldn’t let the limitations of my mind stop me from enjoying the book. Here’s what it did for me: 1) I got a little clearer picture of the four main forces that govern the universe; 2) I was surprised to discover that gravity was the weakest of the four forces, but the one that runs the show (let me not try to explain this paradox, better read the book); 3) I learned about the amazing features of the happenings on the nuclear or subatomic level, and how one particle can appear in two places at the same time; 4) I got a better understanding of how scientists form their theories and how these theories are easily dispelled when just one observation does not match their assumption; 5) I learned about particles and antiparticles, about particles being waves at the same time (or maybe not at the same time, but having the traits of both), about black holes and how they seem to emit light particles and radiation and are not actually black, and so on and so on.
Big Bang vs. the no-boundary theory
There was also a lot of talk about the origin of the universe. The Big Bang theory is still prevalent, it seems (though this edition of the book came out some twenty years ago), but there’s another assumption that Stephen Hawking seemed to be embracing: the no-boundary theory that says that there was no Big Bang, but that space-time is a finite continuum (in the shape of the planet, for example) without a boundary, a beginning or an end. This theory would probably strip away the creator’s power, because there would not have been any creation in the first place.
A funny anecdote
Speaking of creation, Stephen Hawking recounts how the Vatican summoned the most influential scientists to a conference back in the ’80s where they discussed their discoveries and theories. At some point, the Pope invited them all to his private chambers to tell them that it was all fine to continue their research, and that the explorations of the universe were not against the teachings of the Church, but he advised them that inquiring into the moment of creation itself is off-limits, because that infringes on the work of God. 🙂
For desert, I had wormholes and time travel as almost-final chapters of the book, but to make the long story short: Mr. Hawking concludes that time travel is (probably) not possible, at least not at this level. Otherwise, we’d already have tourists from the future making appearances to more reliable witnesses than those that have been telling us about the UFOs for years now.
Stephen Hawking ends with interesting stories about three of the greatest scientists who ever lived: Einstein, Newton and Galilei, but just before this entertaining closure, he gives an optimistic prediction that very soon, probably in our lifetime, we (they, of course) will discover the unified theory that explains all the laws of the universe and, having this technicality out of the way, we can finally focus on questions such as why we are here. He regards this question as much trickier that the question of how the universe started (if it started) and how it works. “If we find the answer to that,” he says, “it would be the ultimate triumph of human reason – for then we would know the mind of God.”