The first half of the book was a well written summary of the development of theories in astronomy and physics, from Aristotle to Newton to Einstein to Heisenberg. It served as a quite digestible refresher to the Grade 11 and 12 physics curriculum. The latter half of the book is where my mind began to be blown.
For example, Hawking explains how we arrived at the theory of the Big Bang, then asked a simple question: Why? If prior to the Big Bang there was no concept of space or time, why were particles and antiparticles created out of nothing? Hawking explains several leading theories, including one involving irrational time that states the Big Bang actually never happens (which I absolutely did not understand).
The theory I found the most intriguing is the anthropic principle. The “weak” version of this argument is used to explain phenomena that appear to be extraordinary. For example, we believe the universe is expanding at a Goldilocks rate that is fast enough to avoid recollapsing due to the attractive forces of gravity but slow enough to support intelligent life. If we were expanding just a bit slower, the universe would have collapsed in on itself by now. The weak anthropic argument is that we should not be surprised that we observe this rate of expansion, because if it was expanding at a different rate, intelligent life capable of asking this very question would not have emerged. A good analogy is if you walked into a neighbourhood with very expensive houses, you should not be surprised if the people living here were wealthy. Of course they're wealthy, how else could they have afforded their house?
The “strong” version of the anthropic principle uses this same argument to explain other more fundamental phenomena in the world, such as Newton’s Gravitational Constant, the charge of an electron, et cetera. We don’t know why these constants are the way they are, but if we even make a minor change, the universe would look totally different. So why is Big G equal to 6.67 × 10-11? We can apply the anthropic argument to easily answer this question and many other questions like this. Yet this goes against the very essence of science. We got to where we are today by asking questions, creating theories, conducting experiments, then modifying our theories when needed. So who’s to say we can’t answer the today’s questions with the Scientific Method too?
In conclusion, A Brief History of Time did not fail to impress me. Hawking explained leading theories in quantum physics at a low enough level for a non-physicist like myself to begin to understand, while also raising many questions that I have never considered before. According to Hawking, with our current level of scientific knowledge, there is still room for the existence of a creator. Thus, I have left the church of Atheism and joined the agnostics. A Brief History of Time has made me both more scientifically informed, yet also more religious. Quite paradoxical, just like our very existence 😉.
Up to now, most scientists have been too occupied with the development of new theories that describe what the universe is to ask the question why. On the other hand, the people whose business it is to ask why, the philosophers, have not been able to keep up with the advance of scientific theories.
IRL Update (01/29/2023): I’m extremely proud of myself for finishing this book, not only because the information was quite difficult to digest, but also because this is the first book I’ve read in its entirety while attending university classes (previous ones were from reading week and winter break). Despite the endless barrage of quizzes, assignments, and other deadlines, I managed to find an hour a night for a little more than two weeks to dedicate to reading. I hope to keep this momentum by continuing to block out an hour a night for reading for the foreseeable future.