Galileo Galilei Essay, Research Paper

The Life and Achievements of Galileo Galilei

The paper which I will be writing will discuss the life, discoveries, and the modern impact of the scientific accomplishments

of Galileo Galilei. Born in Pisa, Italy in 1564, Galileo entered Pisa University as a medical student in 1581 and became a

professor of mathematics at Padua. An astronomer and mathematician, Galileo was, unfortunately for himself, a man ahead

of his time. Galileo discovered the law of uniformly accelerated motion towards the Earth, the parabolic path of projectiles,

and the law that all bodies have weight. Among his other accomplishments was the improvement of the refracting telescope

in 1610 and his advocacy of the Copernican theory which brought him into a conflict of ideas and truths between himself and

the Inquisition. He was condemned by the church whose theories threatened everything that was taught by the priesthood

as the holy truth and he was eventually broken by the Inquisition. Before being ultimately defeated by the church, however,

Galileo made many contributions to the world of physics. His scientific discoveries and endeavors were only a portion of his

contributions to the scientific community. Galileo’s methods of testing and proving his theories were also of major importance

since these painstaking and exact methodologies would lay the groundwork for future scientific discoveries. His brilliance

brought about a new era in scientific advancement and his defeat at the hands of the church put a stop to the scientific

revolution which he had started. In 1993 the Vatican formally recognized the validity of Galileo Galilei’s scientific work.

References Cited

1. GALILEO: PIONEER SCIENTIST – Stillman Drake 1990

2. GALILEO A LIFE – James Reston, Jr. 1941

3. COLLEGE MATHEMATICS JOURNAL – May 1994, Volume 25 Issue 3, p 193

Galileo Galilei was a great scientist and pioneer in the fields of mechanics, astronomy, thermometry, and magnetism, although

mechanics and astronomy were his main passions. He was arguably one of the brightest men who ever lived. Galileo

discovered and enhanced many scientific discoveries of his time period and was highly regarded as a Mathematician and

Natural Philosopher. Galileo was persecuted for his views on Earth’s relationship with the rest of the heavens since he

believed that the Earth revolved around the Sun and that the heavens were constantly changing and evolving. Since Galilei’s

vision of a metamorphosing universe came in direct conflict with the views of Aristotle, views held by and supported by the

church, Galileo was eventually called before the Inquisition and forced to recant his views. Nonetheless, Galileo Galilei made

significant contributions to the scientific community and he is remembered as a great scientist and innovator.

Galileo Galilei was born in 1564 in Pisa, Italy (then a part of the Duchy of Tuscany), to Vincenzo Galilei, a musician, and

Giulia Ammannati. Galileo studied medicine at the university of Pisa from 1581 to 1585, but his real interests were in

mathematics and natural philosophy and Galileo left the university in 1585 without a degree. It was during this time frame

that Galileo began to doubt conventional science, since much of what he was being taught at that time as scientific fact was

conflicting with the evidence which he saw in his hands-on medicalobservations(Hitzeroth, Heerboth, The Importance of

Galileo, pp 14-15). Following his period as a student, Galileo tried his hand at teaching.

Galileo began privately teaching in Florence and he returned to the university of Pisa to teach mathematics in 1589. Galileo

taught at the university of Pisa until 1592 when he was appointed professor of mathematics at Padua (the university of the

Republic of Venice.) Galileo’s duties as a professor of mathematics at Padua were to teach Euclidean geometry and standard

(geocentric) astronomy to medical students. The medical students at that time were expected to know some astronomy in

order to make use of astrology in their medical practices. In Padua, he continued his physics research in the area of mechanics

and astronomy.

In the area of mechanics is where Galileo’s most famous observations were exhibited. The traditional theory accepted by

nearly everyone at that time was Aristotle’s theory that heavier objects, when dropped from the same height as lighter ones,

will fall at a faster rate. In opposition to this notion, Galileo stated that with the removal of outside influences such as wind

resistance, both objects will fall simultaneously at virtually the same speed. Although a very popular story of Galileo states

that he attempted to prove this theory by dropping different weights from the campanile (leaning tower) of the Duomo in Pisa,

this particular experiment was never actually proven to have occurred. However, a similar experiment had already been made

by the Flemish engineer Simon Stevin in 1586. Galileo has said that his interest in Aristotle’s Theory about falling objects

was aroused when, during a hailstorm, he noticed that both large and small hailstones hit the ground at the same time. This

observation caused Galileo to seriously doubt Aristotle’s Theory since according to Aristotle, the larger-sized hailstones would

have had to have fallen from a much greater height and at virtually the same time as the lighter hailstones in order for them

to reach the ground at the same time (which Galileo found very improbable.)

Galileo was also very much interested in astronomy. Tycho Brahe, a Danish astronomer, found a supernova in the

constellation Cassiopeia in 1572 which promptly disappeared two years later. This discovery challenged Aristotle’s theory

of the heavens as perfect, unchanging, and immutable. This discovery, along with another nova appearance in 1604, also

persuaded Galileo to give three public lectures in Padua in his capacity as a professor of mathematics. Galileo used the nova

as an excuse to challenge Aristotle’s views of heavens which were unchanging.

In 1609, Galileo learned of a spyglass that a Dutchman had shown in Venice. Using his own technical skills as a

mathematician and a workman, along with reports of the construction of the device, Galileo made a series of telescopes whose

optical performance was much better than that of the Dutch instrument. The first telescope he constructed had a threefold

magnification, which he quickly improved to 32 times magnification. It was this instrument which Galileo used to develop

his astronomical discoveries.

The numerous astronomical discoveries made by Galileo with the aid of his telescopes were described in a short book called

Message from the stars or Starry Messenger (Sidereus Nuncius) published in Venice in May 1610. In this book, Galileo

claimed to have seen mountains on the Moon, to have proved that the Milky Way was made up of a myriad of tiny stars, and

to have seen four small bodies (moons) orbiting the planet Jupiter. Galileo named the moons of Jupiter the “Medicean stars”.

It was after this discovery of the moons of Jupiter that Galileo became the official mathematician and natural philosopher to

the Grand Duke of Tuscany. It was also during this time frame that Galileo made many mathematical observations of physical

properties.

Among these observations was the discovery that projectiles follow parabolic paths. This discovery allowed arcs of physical

objects to be calculated. Another achievement of Galileo in this time period was the naming of the cycloid curve in 1599.

In 1639, Galileo wrote to Toricelli about the cycloid, saying that he had been studying it’s properties for forty years. Galileo

tried and failed to find the area of a cycloid by comparing it’s area to that of the generating circle. After his failure at trying

to find a mathematical method of finding the area of a cycloid, he tried weighing pieces of metal cut into the shape of the

cycloid. He found that the ratio of the weights was approximately three to one but decided that it was not exactly three.

It was in his employ with the Grand Duke of Tuscany in Florence that Galileo first became involved in disputes about

Copernicanism. Copernicanism was a theory that was posed by Nicolaus Copernicus on the position of the earth in relation

to the heavens. Copernicus had stated in the book On the revolutions of the heavenly spheres (De revolutionibus orbium

coelestium, Nuremberg, 1543), that the Sun (not the Earth) is at rest in the center of the universe and that the earth revolves

around the sun. This theory , also known as the heliocentric theory, was lent credence in Galileo’s eyes when, in 1613, he

discovered that, when seen through the telescope, the planet Venus showed phases resembling those of the Moon, and

therefore Venus must orbit the Sun and not the Earth(Drake, Galileo: Pioneer Scientist, pp. 136 – 137). Galileo went to great

lengths to support Copernicanism in the use of his discoveries and observations, he also used his great mathematical skills to

aid in proving Copernican theories.

Between 1619 and 1624 Galileo adapted a telescope for the viewing of extremely small objects. This microscope, which he

called “occhialini” was composed of the tube of a telescope, of reduced size, furnished with two lenses. Galileo gave his

microscopes to various people, including Federigo Cesi.

It was the support of the Copernican theories which brought Galileo into direct conflict with the Inquisition and the Roman

Catholic Church. Since Copernicanism was in contradiction with Scripture, Galileo was treading on thin ice with the

Inquisition. A young Dominican, Tommaso Caccini, denounced Galileo, his theories, and the Copernican theories officially

from the pulpit during a sermon in the Santa Maria Novella in 1614 (de Santillana, The Crime of Galileo, p. 42). In 1616,

Galileo was officially advised by Cardinal Bellarmino on the behalf of the Pope to proceed with caution and to speak only

hypothetically about the Copernican theory and not as if the theory were reality. Following this confrontation with the

church, Galileo returned to Florence and continued work on his book (Dialogue Concerning theTwo Chief World Systems),

as the Pope wished, Galileo gave more emphasis to mathematical arguments rather than to experimental or physical

arguments.

Although Galileo tried to obey the Pope’s wishes in his wording of the Dialogue, when the book finally appeared in 1632, it

raised an immediate storm of protest leading immediately to the arrest of Galileo and a trial by the Inquisition. The inquisition

found Galileo guilty of publishing a heretical book and insisted that he denounce his theories and confess his “crimes” before

the church. Although he was lead to believe that this act would cause the Inquisition to be lenient (and would keep them from

torturing him to death), Galileo was still sentenced to life imprisonment at his villa in Arcetri near Florence (Reston, Galileo

A Life, pp. 253 – 254.)

It was during this house arrest that Galileo produced perhaps his greatest work, his Discourses on the Two New Sciences ,

which has been hailed as possibly the cornerstone of modern physics. This book was smuggled out of Italy to France and was

published in Leyden in 1638. In this book, Galileo presented the true laws of accelerated motion and falling bodies, as well

as the fundamental theory of projectile motion and important applications of mathematics to a multitude of physical problems.

Galileo died totally blind at 77 years old in 1642. Galileo believed that experimentations and observations of these

experiments was crucial to the scientific process. (Shapere, Galileo A Philisophical Study, p. 126) Although Galileo was a

great scientist, Pope Urban VIII refused to permit Galileo’s burial with a monument, instead, Galileo was buried

unceremoniously in the Church of Santo Croce, in Florence. His remains have since been moved to their present location

in a magnificent tomb opposite that of Michelangelo near the entrance to the church. It was only as recently as 1993 that the

church has admitted that they were wrong and that Galileo’s theories were correct.

Galileo’s extraordinary accomplishments in the fields of mathematics and astronomy upheld and proved the theories of

Copernicus whose theories may have been scoffed at as fantasy. He began the scientific revolution of his time period and

his persecution by the church, unfortunately, put an end to the revolution. He was truly a pioneer. Were it not for Galileo’s

courage of his convictions, many scientific discoveries, including those of other scientists of his era, may never have occurred

or may have been delayed considerably. Without the theories, discoveries, and experiments of Galileo Galilei, we may never

have made it to the moon, been able to examine viruses or germs under a microscope to be able to defeat them, or been able

to write a physical science term paper (on Galileo of course.) If for no other reason than his invention of the microscope,

Galileo deserves to be known as one of the greatest scientists the world has ever known.

References Cited

1. Drake, Stillman – 1990, GALILEO: PIONEER SCIENTIST, The University of Chicago Press, pp. 261

2. Reston, James Jr. – 1941, GALILEO A LIFE, Harper Collins Publishers, pp. 319

3. De Santillana, Giorgio – 1955, THE CRIME OF GALILEO, The University of Chicago Press, pp. 339

4. Hitzeroth, Deborah, Sharon Heerboth – 1961, THE IMPORTANCE OF GALILEO GALILEI, Lucent Books, pp. 95

5. Shapere, Dudley – 1974, GALILEO A PHILOSOPHICAL STUDY, The University of Chicago Press, pp. 161

6 COLLEGE MATHEMATICS JOURNAL – May 1994, Volume 25 Issue 3, p 193