After several months – was it really back in January that I posted my most recent update in this series? – I picked up “The Elegant Universe” again and kept reading. On page 349 (in my edition), Green talks about how there was a moment where the universe from being opaque to being transparent.
He then goes on to describe the moment of the birth of the universe in terms that make me think about how he talks about black holes in the previous chapter (p 342-344?). I’m not a hundred percent sure why, but this part of the book reminded me a little of those four-axis graphs, with space on one axis and time on the other, and black holes sucking in all information. It brought to mind the image of a God’s Eye, or one of those cool graphic design things everybody used to doodle in high school (the nearest I can find via Google Images is the first graph used on this total stranger’s blog entry, but imagine four quadrants of that facing one another).
In the part of the book I’m reading now, Greene says this thing I mentioned earlier about how the universe had a moment where we know it went from opaque to when it went to transparent, and then he talks about how a “gas of freely streaming photons” were able to escape outward.
Now it gets interesting. If you remember back to Homework Takeaway #1: Light Ain’t Old, you’ll remember that photons are light particles.
In other words, if I may be permitted to wax romantic about this for a moment: at the beginning of time and the universe as we know it, there is a precise moment when a burst of photons, i.e. light, began to be emitted out of darkness. In the interest of investigating an age-old metaphor…sounds a little let there be light, doesn’t it?
Oh, and also: We are all made of stars.
Physics is awesome.