Cheat Sheet for Galileo Galilei

Cheat Sheet for Galileo Galilei

Short anecdote: I grew up realizing that many of the ideas of
Aristotle were false, and I sought to prove him wrong. Aristotle
first believed that the Earth was the center of the universe and that
the sun rotated around the Earth. This geocentric view was the
view of most people of my day, and it was staunchly defended by
the Roman Catholic Church. Aristotle also believed that heavier
objects fell to the ground faster than lighter objects. He believed
that the speed in which objects fell was proportionate to its weight.
He believed a ten pound ball, for example, would fall ten times
faster to earth than a one pound ball. Aristotle based this principle
on sensory observations, such as observing a stone and a feather
falling to the ground at the same time. I can’t believe this
erroneous view of falling bodies remained unquestioned for 2000
years. Now according to my first biographer, Viviani, who lived
with me the last three years of my life, I decided to do an
experiment from the top of the great leaning tower of Pisa. Now
this story was never recorded by myself, so many feel that it was
an idea experiment rather than a real one. Nonetheless, it was told
that climbed the stairs of the great leaning tower with two iron
balls, one weighing ten pounds and one weighing one pound. I
raised the two balls and dropped them at exactly the same time.
Both balls hit the ground at the same time. I demonstrated that all
objects fall to the ground at the same speed no matter their weight

1. Birth: I was born in Pisa, Italy on February 15, 1564 and died
January 8, 1642 under house arrest by the Roman Catholic Church.
At least I wasn’t burned at the stake as a heretic.

2. Family and Times: I was the first of six children. Two of my
siblings did not survive infancy. My father Vincenzo was a
musician and composer. My mother Giulia, couldn’t tolerate
stupidity and made sure that I did my studies well. My family
moved to Florence when I was eight, This was a time when the
Roman Catholic Church dominated political and intellectual life. It
was also an exciting time when people were challenging the
traditional geocentric view of the universe and new discoveries
were being made about the laws that governed the natural world. I
never married but had three children out of wedlock with Marina
Gamba.

3. Math Came into my life: I enrolled at the University of Pisa in
1581 to study medicine, but I hated it. I walked by the classroom
where the professor was teaching math and knew mathematics was
the field for me. I persuaded my father that medicine wasn’t my
field and that my true passion was mathematics. In 1589, I was
appointed the chair of mathematics at the University of Pisa. I later
became the chair of mathematics at the University of Padua.

4. Day Job: Chair of mathematics at the University of Pisa and
later University of Padua, teaching geometry, mechanics, and
astronomy.

5. Where did you live? : Primarily in Pisa, Padua, and my country
house outside of Florence.

6. How did you die? : I was found guilty of heresy and sentenced
to house arrest. I went blind in 1638. I died at age 77 on January 8,
1642 due to heart problems.

7. Did you travel much? : I primarily traveled in Italy: Pisa,
Florence, Venice, and Rome.
8. Do you remember why you did math? : See Question #3

9. What obstacles did I encounter? : After I published “Dialogue
Concerning the Two Chief World Systems”, I was summoned to
Rome to face the Inquisition in 1633. I was accused of heresy and
forced to recant my beliefs about the Earth revolving around the
sun.

10. Did you have an attitude? : After recanting my beliefs, I said
under my breath, “And yet it moves” as I left the Inquisition.

11. Most Proud? I was most proud of my work in astronomy. I
invented a refracting telescope that made objects 20 times closer
and used it to observe the rough surface of the moon. I was the first
to note that the moon had mountains and craters just like the Earth.
I also used my telescope to discover four moons of Jupiter, the
phases of Venus, and spots on the Sun. My discoveries in
astronomy helped reinforce my view of a heliocentric universe.

12. What other famous mathematicians? Johann Kepler and I
were good friends and we both shared the view of a heliocentric
universe. Kepler had some strange ideas about tides and orbits that
I did not support. Kepler believed that the moon caused the tides. I
thought this to be ridiculous. He also believed the orbits of the
planets to be in the shape of the elipse. I believe that the circle is
the perfect shape and the only possible path for planets to follow
around the sun.

13. Most admired? I admired Archimedes the most. I thought that
he was a genius.

14. Views of mathematics as a discipline. : I believe that
mathematics was the language in which God created the universe. I

would be a Platonist. I believed that Nature behaves according to
universal mathematical laws, and that these laws may be
discovered by men.

15. What is the math you did:

1. Formula for falling bodies: s = ½ gt2

I discovered that objects fall to Earth at the same rate regardless of
their weight. The distance an object falls is proportional to the
square of the time that it takes to fall.

2. Pendulums: Weight at the end does not affect speed but the
length of the string.

3. Parabolas

Accelerated projectiles follow an ideal trajectory of a parabolic
path. Cannon Balls!

4. Gallileo’s Parradox

Discovered that greater than, less than, and equal to are terms that
can be applied to finite sets. In looking at whether perfect squares
such as 4, 9, and 16 are less numerous than all counting numbers, I
discovered a one-to-one correspondence as one moves to infinity
as each counting number such as 1,2,3,4, etc is also a square root
of a perfect square.

5. Worked with Probability

Rolling three dice will there be a greater chance that the sum will
be 9 or 10.

Sites Used:

http://www-history.mcs.st-and.ac.uk/Mathematicians/Galileo.html

http://www.lucidcafe.com/library/96feb/galileo.html

http://www-history.mcs.st-and.ac.uk/Biographies/Galileo.html

http://www.newadvent.org/cathen/06342b.htm