Read Chapter 1 (pp. 16-46, Toward a Clockwork Universe: Putting the Earth in its Place) of Instant
Physics (Tony Rothman).
Optional reading: The
Mac Tutor biography of Galileo
Write a one-page reaction to or summary of one of the above.
Due: Sept. 15
Monday:
We are getting ready to make our jump from Archimedes to Galileo, so we talked about some of the
intellectual history of the years in between. Between the fall of the Roman Empire and the (European)
Renaissance is a period known as the Middle Ages. And the earlier part of that (around 500 to 1000) is
sometimes called the Dark Ages (the more acceptable, "politically correct" term these days is Early
Middle Ages). During much of this same period the Arab world was experiencing a Golden Age.
The Arab rule grew during the period and included present day Spain, North Africa, the Middle East,
and some of the Caucasus and down into India. The so-called Translation Movement collected all of the
knowledge known at this time and in these regions. Knowledge was valued by the Islamic culture of the
time, and it was considered important to gather the knowledge and put it into the language of the Koran
(the language of God and the rulers).
This collection of wisdom included Greek philosophy, mathematics and science. But it also included ideas from India --
like the mathmetical concept of zero -- which eventually allowed for the Arabic numbers and positional weighting
system -- which are so much more useful than Roman Numerals.
The intellectuals of the day also extended the knowledge of math, astronomy, medicine and so on. Their importance
in intellectual history is sometimes hidden by the Latinized versions of the names of so many Arab scholars. But one
trace can be seen in the many scientific and mathematical words beginning with "al" such as algebra, algorithms, alcohol,
alchemy, alkaline, etc.
Birth of universities in Europe. Scholasticism.
Geocentric (Ptolemy) to Heliocentric (Copernican). Retrograde motion.
Galileo was not the inventor of the telescope, but he was an early adopter and he made some improvements on it and
pointed it toward the "heavens". He noted that the Moon has craters. Many of the astronomical thoughts of the time
included a notion of the perfection of the heavens -- perfect spheres orbiting in perfect circles, etc. So this
crater-pocked Moon brought some of these ideas into question.
Galileo also observed the moons of Jupiter, which he named Cosmica Sidera ("Cosimo's stars") after Cosimo II de' Medici.
Observing an object orbit something other than the Earth (or even the sun) was a revelation.
