The Grand Design (2010)
Stephen Hawking and Leonard Mlodinow
Rating: 6/10
Overview: Well, this book certainly tackles some tough physics subjects and presents them so the lay person (e.g. someone like me) can get their head around it. I asked a real-live theoretical physicist some questions about the book, and since I was able to articulate the theories reasonably well, I’d say the authors did a pretty good job.
The authors take the reader step-by-step (more or less) from how physicists look at the universe, to how they model theories about the universe, to how the idea of multiple realities (and universes) fit into “M-theory” (the current reigning champ of physics), to how all of this points to a “grand design” that can be explained by science.
I’ll briefly attempt to hit the main points of the book (wish me luck), informed by my talk with the physicist (let’s call him T-dogg), and then I’ll give my reaction to some of the theories described.
The Meat & Potatoes:
(You'll get it later).
So basically physicists have been trying to figure out models and theories that explain the workings of the universe. The Newtonian way of looking at things has worked pretty well for bigger things, but does not work so well on the quantum (really, really tiny) scale—that’s what quantum theories are for. The physics “holy grail” is to find a single model/theory that encompasses both scales in one unified theory.
Before we begin with the difficult stuff, they lay out that there are four known forces governing our universe: Gravity, electromagnetism, the strong force (what binds neutrons and protons together in the cores of atoms), and the weak force (something that causes radioactivity and formed important stuff in the early universe). Physicists have tried to find quantum theories of all these forces to explain workings at the scale.
It seems they (by “they” I mean the physics community in aggregate) have mostly given up on this quest. Instead, they have what is called “M-theory” (with no agreement on what the “M” stands for). But the gist of this theory is that it encompasses a whole range of models that are used in specific situations in the universe—basically the Swiss-army knife of physics. Or it might become one big fundamental model as it gets refined. Part of the issue is our technological ineptitude; however far we seem to have come, there’s always some things out of reach that just can’t be verified through direct observation (too small or too big). [T-dogg says that the CERN supercollider will help cull some of these theories with its experiments, thereby making M-theory even leaner].
But, even in the things that are observable, some results were just difficult to make sense of (like how shooting molecules through two slits results in patterns that don’t make intuitive sense). In a sort of chicken or egg situation (as far as I
Relax Tyra, you wouldn't even notice. Gosh, you're such a diva!
understood it), a physicist (Feynman) came up with some math to explain these counter-intuitive findings, and they trust the math. The authors wish to point out, however, that the same math that makes sense of this odd pattern, also allows for the molecules traveling through the slits to take all the infinite paths available (e.g. the molecule traveling straight through the slit or the molecule looping around Jupiter twice before going through the slit) and at the same time. The probabilities of what path the molecules take is what’s important; i.e. it’s more probable that the molecules will go through the slits rather than through Tyra Bank’s underwear first.
Toss in the assertion that observation alters what you’re observing (Heisenberg’s Uncertainty Principle and quantum physics), and at the quantum level, even though one could observe a particle at any point along its path, in-between those observations that particle is still taking every path imaginable and simultaneously. This leads to the conclusion that the observations one makes on a thing in the present affects its past (and hence, there is no single past (or history) of that thing.
[T-dogg says most physicists understand that extrapolation, but don’t care about all those other paths since it doesn’t really help with their work].
With me so far?
Don't buy real estate in these dimensions!
The authors then go on to say a similar thing about our universe(s); i.e. there are an infinite number of universes (well, 10500 of them) with 11 space/time dimensions each, and each of those dimensions are present in various forms in all the different universes. In our universe, all but 3 dimensions (plus time) are wound so infinitely tight and small, that they’re unobservable. And, according to the authors, all physicists care about is our universe, not what occurs in the other universes since we’re operating within the parameters of our particular universe (i.e. those 4 dimensions we live in). Further, since particles are made up of patterns of vibration (or “strings”—hence String Theory), those curled up dimensions determine the “laws of nature” (e.g. the charge of an electron or how particles interact with each other) in any particular universe (and are constrained by the math making all of this possible).
Still with me? (Don’t worry, I’m not sure I’m even with me at this point).
Let’s take a step back; at first scientists explained everything they could observe with their own eyes or early scientific tools, using mathematical models. As our technological advances allowed us to observe more, things got complicated. “Then came quantum uncertainty, curved space, quarks, strings, and extra dimensions, and the net result of their labor is 10500 universes, each with different laws, only one of which corresponds to the universe as we know it” (p. 119).
Okay, so what does this mean for the origin of our universe and where it’s going? Well, the authors argue that the Big Bang (BB) is pretty well supported through observation and mathematical models. (The BB theory, if you recall, is that all matter was condensed into a singularity (a point with infinite mass) that expanded and gave birth to galaxies, stars, and us. It’s also a really good TV show). That theory qualifies the origin of the universe as a quantum event, and, being such, “the universe appeared spontaneously, starting off in every possible way” (p.136). And, given the current theories and math, time began with the beginning of the universe since it functions differently at the quantum level: “the question of what happened before the beginning of the universe is rendered meaningless” (p.135).
But where it the universe going? Well, it’s stretching out, and they use the analogy of the surface of an expanding balloon. If we (and other galaxies) are all at different points on the surface of a balloon that is blowing up (i.e. stretching), then things are getting further apart while their relative position to each other remains the same. A few solutions to the mathematics reveals that the universe will either a) contract back on itself; b) expand forever; or c) the expansion will slow to near zero but never quite reach stalling.
The authors conclude: “For these reasons M-theory is the only candidate for a complete theory of the universe. If it is finite—and this has yet to be proved—it will be a model of a universe that creates itself” (p.181).
Issues Raised
Well, if you got this far, and if I did a reasonable job summing the book up as objectively as I could, perhaps their description of the universe raised some questions for you. It certainly did for me!
1. Much of their modeling depends on math—a man-made device. Sure there is some universality to it, but I’ve always viewed math as an incomplete, albeit sophisticated tool. Why? One question: what is any number divided by zero? (Answer: “undefined” or “meaningless.”) What? One of the most fundamental numbers in mathematics has undefined/meaningless attached to it? Riiiight.
2. Several times throughout the book, the authors seem to dismiss a fundamental question as “meaningless” simply because…well, I’m not sure why. I think it’s because their mathematical model doesn’t support it (e.g. what existed before the beginning of the universe). Or how about the balloon analogy? My question is: what is the “balloon universe” expanding into? (T-dogg said it doesn’t matter because we can’t observe it—it’s outside the realm of our understanding).
3. The authors tend to take digs at religion throughout the whole book. (Miracles, intelligent design, etc.). While I’m not religious myself, it seems a little funny for them to denigrate a set of beliefs when they have essentially invented dimensions and universes to “make the math work” in their own description of the universe. Of course, I’m sure to most lay people, the idea that a particle traveling through a slit to a detection board takes every possible path at the same time is equally superstitious-sounding. They dismiss things they can’t explain (beginning of time and what is outside the expanding balloon), and yet it is tenets in religion that try to provide an explanation for these very things. I’m not saying one side is right, I’m just saying that both sides are suspect on issues that the human mind has trouble comprehending, and both sides have found a safe haven to ease that cognitive dissonance (i.e. faith or math).
4. And, if things at the particle level are so infinitely possible, why isn’t it possible for things to happen at the quantum scale that could result in observable “miracles?” If all paths/histories are viable, why couldn’t water molecules change just enough to allow someone to walk on them for a brief time? Sure the probability might be incredibly low, but not impossible—and that makes all the difference in the universe.
5. There often seems to be some sort of exception made whenever something doesn’t agree with a well-established theory. For example, Einstein’s relativity postulate that nothing can move faster than the speed of light has been a staple ever since he stuck his tongue out to decorate college dorm rooms and t-shirts. Yet, in order for the expansion of the Big Bang to have taken place, things had to have moved faster than the speed of light. Their answer? That speed limit does not apply to the expansion of space itself (even though we could not have—and currently cannot—observe such a thing; it’s all in the math).
In the end, I gave the book a 6/10 because, although a lot of it seemed funky to me, it did present some awfully complicated theories in a way that even I could understand it (given my conversation with T-dogg). But in the end, it merely opened up more questions for me about science rather than impressing me that we’re on the verge of really understanding the universe and all its mysteries.