Camille Flammarion, L’Atmosphere: Météorologie Populaire (Paris, 1888)
I’ve been inundating you with issues in symmetry, but I hope you don’t mind. I’m now in the midst of Chapter 4, which deals with (among much else) the homogeneity and isotropy of the universe and the related symmetries in physical laws. One of the starting points for this discussion is the Copernican Revolution.
You know the basic story. The ancients (and especially Aristotle and Ptolemy) thought the planets and sun revolved around the earth. Ultimately, Copernicus rediscovered the Heliocentric model of Aristarchus, and thanks to Kepler, Galileo, Newton, and others, we ultimately learned that we aren’t at the center of the universe.
That’s the condensed version, anyway. It’s tough to put a new take on the story since most people have heard variants of it so many times that it’s become stale. In the process of writing it, I was describing the Copernican Revolution to my wife, pointing out that Aristotle posited a spherical earth as obvious. She said something along the lines of, “Wait! Didn’t people used to believe that the earth was flat? Why did we learn that?”
I started thinking about it, and realized that this is one of many misconceptions people have about what people did or didn’t believe at various times. As Stephen Jay Gould put it:
there never was a period of ‘flat earth darkness’ among scholars (regardless of how the public at large may have conceptualized our planet both then and now). Greek knowledge of sphericity never faded, and all major medieval scholars accepted the earth’s roundness as an established fact of cosmology.
And while the geocentric universe was generally accepted, it wasn’t uncontested. As I mentioned above, Aristarchus was among the first to posit that the sun was at the center of the universe. It is simply wrong that no-one had thought of a heliocentric universe before Copernicus.
So a couple of questions to you folks:
- What are some other examples of historical misconceptions about misconceptions that you’d like to see discussed?
- Anything you’d like to see about the Copernican Revolution that doesn’t get discussed in the standard treatment?
Oh, and speaking of our place in the universe, I’m giving a free public talk next weekend. Here are the details:
- What: “‘What is the Universe Expanding into?’ and other perfectly reasonable questions.”
This is a general talk that covers much of the material that we discuss in Chapter 6 of the User’s Guide. It will be aimed at a lay audience, and there will be lots of time for questions.
- When: Saturday, January 14, 2012. 9:30am. Doors open at 8:15, and the Q&A typically ends at 11:15.
- Where: Princeton Plasma Labs as part of their Science on Saturday program. Directions are here.
Hope to see you there.