The Universe: Leading Scientists Explore the Origin, Mysteries, and Future of the Cosmos by John Brockman
My rating: 4 of 5 stars
This book is a crazy mess because the Edge Organization threw together these essays by these brilliant physicists that were written for a particular audience with some background understanding of physics and maybe even some interest in the personal biographies of these scientists. Reading this book is like having alphabet soup spilled onto the table and trying to spell out the alphabet using only your nose.
That said, I learned how scientists are on different sides of numerous debates about what the universe is doing, how - or even if- it began, as well as having numerous side arguments on the differences between science, math, and philosophy. I learned about how a bunch of people came to be interested in becoming physicists and some of their happiest and saddest career moments.
I learned about the inflationary theory of the universe to explain why the universe slowed down expansion and then relatively recently started accelerating. First of all, holy cow. Location-wise, we're not anywhere special in the universe, but we are in a particular place in time where the expansion of the universe has changed from decelerating to accelerating.
The theory is basically that there's a black energy patch and at very high energies it has a repulsionary force. It's own repulsion causes it and the universe to expand quickly. Dark energy is 60 % of the total mass energy of the universe. Whereas the parts we understand, molecules, atoms, neutrons, and protons, are only 5% of the universe. The dark energy is causing the acceleration and making the universe more homogeneous and isotropic driving it into a vacuum state.
I learned about the theory of a Cyclic Universe. The conventional model of Big Bang Theory is not the theory of the bang itself but only what happened after. The consensus model = Big Bang Model (1920-40s) + Alan Guth's inflationary model (1980s) + recent amendment of dark energy. Consensus model says there was a beginning to time.
The cyclical universe is an alternative theory that says that time is endless and space is endless, evolution of the universe is cyclical. The biggest problem with this model is that every expansion and contraction would cause more energy and entropy. Extrapolating back in time they would shrink to nothing- and there would still be a beginning. The new cyclic model seeks to overcome this problem.
Also, quantum physics, yo. Classical physics describes the universe deterministic equations. The real world is described with quantum mechanics, in terms of probabilities. The uniform theory is just the average of the probabilities, but the reality is that there would be ripples, more mass here and there. Today we can see the ripples in the background radiation that were predicted many years ago.
So that leads us to String Theory! But wait, that's boring. Stings are 1-dimensional. There are extra dimensions. (This I'd heard about before.) In one version- The universe has a total of 11 dimensions: 6 of them are curled into a tiny ball. (3 spatial dimensions, 1 time dimensions, and one additional dimension.) The multi-dimensional version of this "String" are called a "branes" (as in membranes)?
So in String Theory theres 4 dimensions + the time dimensions (called the "bulk") that is sandwiched between two membranes. We can only move along the three dimensions of our brane and can't see the other brane. But our brane has collided with the other brane governed by a force that acts like a spring. In the first period the branes remain a fixed distance apart while our three dimensions stretch over trillions of years. As the membranes pull towards each other it creates ripples in the membranes. Then the branes come closer, accelerating as they get closer, collide and bounce back, the stretching begins again.
Additionally, there's some discussion of the possibility that we're just a simulation by super intelligent super computer (Chapter 8). This essay I pretty much just disregarded because it doesn't feel true. Haha. But then in a later essay (Chapter 17) about how the universe functions like a big super computer, I had to reconsider the previous argument. The universe functioning like a huge computer is really one of the most profound and confusing ideas I've come across in a while.
Actually I have no idea if any of that is right because physics, and this book, are both really confusing. So basically, would I recommend this book? No, it's a mess. Did I love it? A little bit yes.
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