Scientists from the Classical Period:

Eratosthenes	c. 300 BC	Egyptian "Librarian"	Headed the great Library of Alexandria. He performed the first quantitative measure of the Earth's circumference for which a historical record has been preserved. Estimate within 10 % of the modern value.
Aristotle	c. 300 BC	Greek Scientist	Articulated ancient understanding of motion on Earth and in the Heavens with the Earth at the center of the Universe. Articulated ancient paradigm that Heavens (Stars, Sun, moon and planets) are governed by laws different than Earthly objects. Proposed that heavenly bodies are "by their nature" in motion whereas earthly objects are "by their nature" at rest.
Euclid	c. 300 BC	Greek  Mathematician  of Alexandria	The most prominent mathematician of Greco-Roman antiquity, best known for his treatise on geometry, the Elements.
Aristarchus	c. 200 BC	Of Samos	Calculated relative distances to and sizes of the moon and the sun. Showed that the Sun is much larger than the Earth from which he argued that the Sun is the center of the Universe.
Ptolomy	c. 200 AD	Greek Scientist	Developed phenomenological model for planetary motion based on circles and epicycles with the Earth at the center.

 

Scientists from the Middle Ages:

Al-khwarizmi, Muhammad Ibn Musa	780-850 AD	Islamic Mathmetician	Muslim mathematician and astronomer whose major works introduced Hindu-Arabic numerals and the concepts of algebra into European mathematics. He lived in Baghdad in the first golden age of Islamic science. His work on elementary mathematics, Kitab al-jabr wa al-muqabalah ("The Book of Integration and Equation"), was translated into Latin in the 12th century and originated the term algebra.  Latinization of his name led to the term "algorithm".
Ibn Sina, (Avicenna)	980-1037 AD	Persian Scientist and Physician	His Kitab ash-shifa' is probably the largest work of its kind ever written by one man. It treats of logic, the natural sciences, including psychology, the quadrivium (geometry, astronomy, arithmetic, and music), and metaphysics, but there is no real exposition of ethics or of politics. His thought in this work owes a great deal to Aristotle but also to other Greek influences and to Neoplatonism.
Ibn Al-Haitham	965-1039	Islamic Scientist	Considered by some as the most important optician between Euclid and the Renaissance.  HIs book Kitab-al-Manazir (Book of Optics) describes imporant optical laws such as light travels via the shortest path.
Fibanacci, Leonardo (also known as Leonardo Pisano)	b. c. 1170, d. after 1240	Italian mathematician	Wrote Liber abaci (1202; "Book of the Abacus"), the first European work on Indian and Arabian mathematics. At the time Hindu-Arabic numerals were known to only a few European intellectuals through translations of the writings of the 9th-century Arab mathematician al-Khwarizmi. Many other mathematical advances, e.g., Fibanacci numbers.

 
 

Scientists from the Renaissance:

Copernicus	1473-1543	Polish Astronomer	Revived ancient idea that the earth went around the Sun. Did not abandon the ancient idea that the heavenly bodies moved in circles. Had to use epicycles for his phenomenolgical model of the planets' orbits to be as accurate as Ptolemy.
Brahe, Tycho	1547-1601	Aristocrat, Danish Astronomer	Led team to map the motion of the planets which were the most accurate measurements of the day. Became the established measurements from which to fit into the phenomenological models. Also the most accurate naked eye measurements ever made before or since.
Kepler, Johannes	1571-1630	German Astronomer	Born poor but Protestant which in Protestant controlled Germany allowed him opportunities not available to people of other faiths. First scientist to abandon orbital models based on circles and epicycles. Developed an accurate phenomenological model for planetary motion. Developed three laws regarding planetary motion: (1) planets orbit the sun in elliptical orbits, (2) the speed of the planets changed during their orbit and was roughly proportional to its distance from the Sun or the area sweep out by a planet in its orbit is equal for equal times, and (3) the period squared is proportional to the length of the orbit with each planet obeying the same proportionality constant.
Galileo,	1564-1642	Italian Astronomer, Scientist	Outspoken Copernican which led to the famous trials and his house arrest. Created and used telescope to look at the Heavens. Observed mountains on the moon, moons of Jupiter and phases of Venus. First scientist known to use the experimental method. Studied balls rolling down incline planes. Suggested that in the absence of air resistance the acceleration of gravity would constant and all object would have the same acceleration. Explicitly he showed that the distance an object falls is proportional to the time squared. Developed concepts of inertia and superposition.
Descartes, Rene	1596-1650	French Intellectual	Wrote "I think therefore I am." Master of deduction. Proposed a conservation law for motion in the Universe.
Newton, Sir Isaac	1642-1727	English Mathematician and Scientist	Wrote Pincipia (1682) in which he introduced three laws including the concept of Force (F=ma). These laws provided a framework for understanding physical processes and became basis of all Physics (and much other thought) during the 18th - 19 th centuries. Applied his framework to explain Kepler's Laws by introducing a universal force of gravity (F = GMm/R2 ). Showed that the same force which causes an apple to drop also keeps the Moon orbiting the Earth which overturned Aristotle's proposition that heavenly and Earthly objects obey different laws. Developed the field of differential and integral Calculus among other achievements. Arguably the single most influential human to have ever lived, he wrote "If I have seen farther than others, it is because I have stood on the shoulders of giants."

 
 

Scientists who defined classical physics after Newton :
 

Electro-magnetism:
 

Franklin, Benjamin	1706 - 1790	American Businessman, Physicist and Diplomat	Wrote (1751) "Experiments and Observations on Electricity," the first comprehensive study in the field. Developed the concepts of positive and negative charge and showed that like charges repel and opposites attract.
Coulomb, Charles	1736 - 1806	French Engineer and Physicist	Showed that electrical forces obey an inverse square law (F=kQq/R2) similar to the gravitational force law discovered by Newton.
Faraday, Michael	1791 - 1867	English Chemist and Physicist	Born to a working class family and had no formal training in science. Developed the concepts of electrical and magnetic fields. Showed that a changing magnetic field can produce an electrical field and vice-versa.
Maxwell, James Clerk	1831 - 1879	Scottish Physicist	Developed a general mathematical formulation for the diverse phenomena of electricity and magnetism. Showed that visible light was an example of a self-sustaining electromagnetic wave. Introduced the aether as the medium for light wave propogation.

 

Thermodynamics:
  NOT NINISHED 9-21-03

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