Back in March I mentioned that I was going to read Brian Greene’s book The Fabric of the Cosmos: Space, Time and the Texture of Reality. Brian Greene is a physicist currently working in the area of string theory. Fortunately for the rest of us he is also a man who can demystify modern physics for the masses. In this book he takes the casual reader on an adventure into the nature of reality. I think you will find that this adventure is beyond the wildest ride you can imagine at any theme park. To call our universe amazing is to damn it with faint praise.
Today I actually finished the 569-page tome. Yes, it took over four months to read it. Greene is excellent at making analogies so that we laypeople can wrap our minds around something so abstract as physics. Even so this is not the casual sort of book you bring to the beach with you. I doubt you spend hours curled up in your hammock reading it, fascinating though it is. I got through it in snippets of 15 minutes or so at bedtime. I did this because I found that 15 minutes was about the maximum my brain could stretch in one day. I generally needed a day or so to process what I had learned. Sometimes I had to go back and read parts again: did he really say that?
So the book is still daunting but well worthy of the read. Physics is not a subject that interests most people. Still physicists try to describe the reality of the world that we live in, and what we observe is but a tiny fraction of the reality. Since we spend our existence in this reality you would think we would care more about understanding this box that frames our existence. Most of us think we understand reality but it takes a physicist to show us that we really don’t understand squat. The problem is that it is daunting to communicate to the layperson the nature of reality. When we think about concepts like Einstein’s General Theory of Relativity we reach for the Excedrin. We figure there is no way to understand it except to spend years learning calculus and sifting through the equations. Fortunately thanks to Greene and other writers you don’t have to. He does an excellent job explaining both the special and general theories of relativity, and this entity he calls space-time in which we live our lives. In clear analogies and illustrations you will find that you too can grasp ideas like why time slows as one moves toward the speed of light or how space itself can be curved.
If an appreciation for special and general relativity weren’t enough, the second half of the book takes us into the far more mysterious world of quantum physics. You don’t have to get too far into the quantum physics portion of the book before you say to yourself, “Gosh, this stuff is so amazing it should be in a science fiction book.” And that’s the point: what we understand about our reality really is amazing. You should be awed by the time you finish this book. Those crazy, nerdy physicists are onto amazing stuff. We have mystics and theologians who try to tell us what lies beyond: physicists are pulling back the gauzy curtains that frame our vision of reality to show us the beauty and mystery of what lies behind the curtains.
Although I am not sure Brian Greene would share my assessment I feel physicists are tantalizingly close to joining two universes that hitherto have been as separate as oil and water: science and religion. Actually I’d describe it more as physics and metaphysics. I’ll have more on this in a blog entry soon. Reading Greene’s book made me realize that we were knocking on God’s door. The mysticism that embraces much of our most profound needs and hungers is peeling away. The good news: the universe is an awesome place.
Here are capsule summaries of some of the main ideas I took away from the book. If Brian Greene were to read this review I suspect he would caveat it, footnote parts of it and say certain of my observations are in error. If so some translation errors are to be expected on a book of such depth.
The Universe is principally space pervaded by energy that we can see and cannot see. It is pervasive and it is everywhere. There is no part of the universe that is not alive with energy. The whole notion of a vacuum is a misnomer. There is no space in our universe that is untouched by some form of energy. A vacuum is an area of space with no matter in it. But as I learned about halfway through the book energy and matter truly are the same thing. We learn that E=mc2 but we don’t really understand what this means. It means that mass is a property of energy. In fact there is nothing that is truly solid. Mass and energy are bound up together. So a vacuum, even if it can be construed as empty of matter, is never empty of energy. Even an empty chamber at the center of the earth is coursing with cosmic rays. To me it is not unrealistic to say the universe itself is alive.
Moreover within this boundary of reality that we can perceive nothing ever really perishes. Form may change. I doubtless will die as a homo sapien some day but the matter that makes up this thing I call me is as external as space-time. Some of my matter will decompose into simpler elements. Some of my matter will become energy. I am never destroyed. I only change form. The big question to be discussed in another blog entry is whether I have a soul and whether that unique signature that is me survives death.
What is there to understand about quantum mechanics? Fundamentally it is about uncertainty. Uncertainty is hardwired into our universe. At the subatomic level there is no guarantee of any outcome. We can only speak about probabilities of outcomes. It seems counterintuitive that the more precisely we try to measure something the less certain we are of the outcome. But this is the undeniable truth.
And what exactly is the nature of reality? At the quantum level Greene makes the assertion that things that frame our notion of reality cease to exist. There is no time. Time can only be perceived at the macro level. Indeed toward the latter chapters we come to understand that space-time itself may be an illusion. Everything we perceive or think we perceive may well exist in a two dimensional universe. Our existence may well be on the edge of an enormous balloon.
String theory tries to tie quantum theory with the general theory of relativity. Here we enter a world of the theoretical since strings are too small to be seen: they can only be reasonably inferred. Like a dot on a picture tube of the monitor that you are reading this on there are areas too tiny to be observed. There are only mathematical models to work with. Linear accelerators may give credence to certain string theories over others but there appears to be no way to prove that strings exist. But as our models get better and as the math used in them gets more rigorous we can reasonably infer the rules by which quantum physics and that which we call particles operate.
I strongly recommend this book. Life is too short to spend ignorant of the nature of reality. What we teach in school covers a tiny percentage of the truth, and the truth of our reality is always becoming better understood. I think courses on relativity, quantum physics and string theory should be a requirement for any college diploma. It’s not necessary to be down in the weeds with the physicists on the mathematics to get an appreciation for our amazing universe. But it does take time and effort to truly have a decent understanding of who we are and our place in this thing we call reality. Books like Greene’s are invaluable. For a curious mind to get through life ignorant of such amazing discoveries means in some sense to live the unexamined life.