Speed Laws
In Ptolemy’s system, the point on the deferent moves uniformly as viewed from a point called the equant point, or sometimes just equant. The equant, the center of the deferent, and Earth all lie in a straight line, with the center midway between Earth and the equant.
Cantor’s Paradise
No one shall expel us from the Paradise that Cantor has created for us.
—Hilbert, “Über das Unendliche” [On the Infinite], in Mathematische Annalen 95 (1925)
I used to believe these myths about the history of set theory:
Filed under History, Set Theory
These notes are not a systematic “Introduction to Set Theory”. I intend them as a
blend of history, intuition, and exposition, with an occasional dash of philosophy.
Filed under Set Theory
I’ll begin with Kepler’s first two laws, and work backwards to Ptolemy’s system. Seeing Keplerian astronomy recast this way will expose the bones of the Ptolemaic system.
Deferents and Epicycles
Quite some time ago I started writing up notes, for my own amusement, on the history of astronomy. I’ve worked on it on-an-off over the years, but there always seems to be a bit more I should add. Eventually the pdf version will be ready for prime time. Meanwhile I’ve decided to convert what I have into a series of posts. Enjoy!
Filed under History Book Club
Here it is:
Apparently two-sided limits are problematic in 2024.
Filed under Bagatelles, Math
Still from Ikiru
Another post from the History Book Club, based on:
Filed under History, History Book Club
Another post from the History Book Club.
Donald Kagan: Ancient Greek History; The Peloponnesian War
Filed under History, History Book Club
| Reflection groups -… on Set Theory Jottings 5. Zermelo… | |
 | Bhupinder Singh Anan… on Set Theory Jottings 29. D… |
 | Michael Weiss on Set Theory Jottings 29. D… |
| Bhupinder Singh Anan… on Set Theory Jottings 29. D… |
| Michael Weiss on Aristotle and Falling Obj… |
