Re: Ch. 3: Let There Be Light
In this chapter we move away from almost pure (informed) speculation
to information gleaned by observations and experimentation
(although there is still some speculation).
We also have the last chapter with a biblical reference for a title, in fact the only one that is a direct quote. Genesis, Chap. 1, Verse 3 (KJV).
Admittedly, the first few pages deal with that period when we can make no direct observation, but must rely on the informed speculation I mentioned earlier. Then Tyson comes to a description of light gained from our O&E (observation and experimentatjion). Sometimes light behaves like a continuous wave, at other times like a discrete particle (photon). We also learn that light waves can be categorized from the very high energy, very short waves of cosmic and x-radiation to the (relatively) long and weak radio waves we use to broadcast radio and television. Visible light is some where in the middle, and thanks to (the very busy) Isaac Newton, we know it can be broken down into what we recognize as color.
I found it personally interesting that the breakthrough in background CMB radiation came not from academia, but from industry. In 1963, I was teaching science in the Dallas, Texas public school system. I was invited to take some of my brighter students on a field trip to the regional long-distance telephone facilities of AT&T. It is amazing to think what was considered ground-breaking in those days, but today is already past history and out of date. No, I did not meet Penzias and Wilson, but did see some of the early results of their work.
Tyson briefly mentions Dark Matter and Dark Energy (each of which is given its own chapter later in tis book), he mentions the use of spectoscopy and spectrometry (if you don't know the difference, look it up), and how they are used to analyze light waves. There, I have told you all I know about the subject (it was at about this point in my career when I switched from science to law). If you are interested in learning more about the subject, here is a link: http://loke.as.arizona.edu/~ckulesa/cam ... intro.html