I am now in the middle of this wonderful book. Janna Levin has made the book accessible to those scientifically challenged, like myself. People already familiar with the scope of the book may still find it interesting because she liberally doses the book with anecdotes about the quirks of the different people that has opened up the body of knowledge she is now trying to explain and expand.
The first few chapters are really a recapitulation of what any college, even high school level student might have taken up. Newtonian physics, Special Relativity, General Relativity, Quantum theory, black Holes and the Big Bang. I have encountered this topics before and quite familiar with them, but two insights (?), points that Ms. Levin makes me realize how beautiful the universe is.
The first one, is that the theory of General Relativity was created because the Special Theory of Relativity conflicted with Newton's Theory of Gravity.
"despite the impeccable condition of Newton's theory, Einstein realized that gravity violated one of the sacred tenets of special relativity. As mentioned, the main conflict with special relativity is that Newtonian gravity allows information to be communicated faster than the speed of light. If the sun were to suddenly collapse, according to Newton's theory we would immediately feel the gravitational change. This is no different from expecting an event in Iceland to instantaneously later the course of events in China. Einstein's theory of special relativity forbids anything, any form of information, to travel faster than the speed of light. Information of any kind must be encoded in the form of energy or mass, after all E=mc2. Information is encrypted on stuff, and stuff travel slower than, or at, the speed of light. The force of gravity should be no exception. Any information about gravitational change, should travel slower than, or at, the speed of light. To ensure this, Einstein had to discover the essence of gravity..." (page 45)And he did, he had to learn Riemannian geometry to do it, so he did. This is a very concrete example of how the scientific method works, you find a conflict in theories and you find an explanation (theory) that better fits reality. And all of humankind benefits.
The other point is this:
"...In the primordial universe there was essentially only hydrogen and helium with only trace amounts of heavier elements. There was no oxygen and no carbon, and so no water and no basis for organic life. The primordial universe was a sterile cauldron.She may have been in Columbia, but I was in a jeepney commuting to work when I realized this. It was a humbling yet euphoric moment. To be made of the stuff of stars, What a feeling.
Much of the material synthesized in the center of stars gets ejected back out into space when the star dies. Eventually new stars and planets can form from the star's scattered remains. This next generation of stars, and more importantly, their satellite planets, can be made from heavier elements like carbon and oxygen. Plasma can form on the surface of planets. Maybe on one with optimal conditions, complex molecules form and an inanimate broth waits for the sparks to generate organic life. Voila. a few hundred million years later, Africa blooms and here we are.
We have the peculiar realization that we are made of the stuff of stars. I was sitting on the back of my astronomy class at Columbia when I learned this." (page 80)
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