Biographies of some Famous Physicists

(Thomas O’Sullivan ’97)


Aristarchus of Samos - Greek - (310 - 264 B.C.) First person to maintain that the earth revolves around the sun.

Claudius Ptolemaeus (Known as Ptolemy) - Greek/Egypt - (100 - 178 A.D.): Put in place a system which maintained that the sun was the earth was the centre of the universe (a theory first (?) mentioned by Aristotle). Not until 1543 was this ptolemaic system superseded by the theory of Copernicus.

Nicholaus Copernicus - Poland - (1573 - 1543): He postulated the sun, not the earth, is the centre of the solar system.

Tycho Brahe - Holland -(1546 - 1601): Made astronomical observations that were used by Kepler. Proved that comets actually are outside the earth’s atmosphere.

Johannes Kepler - German - (1571 - 1630): Proved using Brahe’s results that the planets orbit the sun in elliptical paths and formulated three laws of planetary motion.

Galileo Gallilei - Pisa - (1564 - 1642): Discovered that all falling bodies would experience the same motion if air resistance was neglected. He made one of the first astronomical telescopes in Europe. He agreed with Copernicus’ view of the solar system, but was forced to renounce this view by the church. He is known as the father of modern physics.

Willebrord Snell - Holland - (1592-1626) Discovered the law of refraction but it went unnoticed until Huygens referred to it nearly 80 years after its discovery

Albert Michelson - USA - (1852 - 1931) best remembered for his terrestrial method for measuring the speed of light using a rotating octagonal mirror.

Isaac Newton - England - (1642 - 1727): Three laws of motion, the law of gravitation, the separation of white light into its constituent colours, the reflecting telescope and the corpuscular theory of light.

William Parsons "Earl of Rosse" - England - (1800 - 1867): Installed a telescope in Birr castle in 1845 which was the largest in the world for over 50 years.

Christiaan Huygens - Holland - (1629 - 1625); Wave theory of light , pendulum clock and astronomical observations.

Thomas Young - England - (1773 - 1829): Demonstrated experimentally that light has a wave nature by showing interference and diffraction. He suggested that light was a transverse wave. He discovered the reason for astigmatism and realised that the lens in the eye could alter its focal length.

Joseph Van Franhofer - Germany - (1786 - 1826): Measured the wavelengths of the dark lines in the suns spectrum which, consequently bear his name.

Christian Johann Doppler - Austria - (1803 - 1853): Proposed that the frequency of a moving wave source would appear different to stationary observers or observers moving with a different velocity relative to the source.

Blaise Paschal - France - (1623 - 1662) He Proposed a law of pressure in fluids, he invented a calculating machine and he developed the theory of probability.

Robert Boyle - Ireland - (1627 - 1691): He designed a vacuum pump which he used to show that sound needs a medium and that a feather and a piece of lead fall with the same acceleration. He studied gases and proposed a gas law. He developed the scientific method. Known as the father of modern chemistry.

Anders Celcius - Sweden - (1701 - 1774): Best remembered for anatomy studies and devising a scale of temperature.

William Thomson - Lord Kelvin - Ireland - (1824 - 1907): Deduce absolute zero and proposed a temperature using Celcius’ divisions but starting at absolute zero (-273.15° C).

Robert Brown - Scotland - (1773 - 1858): Primarily a botanist, but discovered the rapid random motion of pollen grains suspended in water, which was the first experimental evidence of the molecular theory.

Amadeo Avogadra - Italy - (1776 - 1856): In 1811 he proposed that equal volumes of gases at equal pressure and temperature contain equal numbers of molecules.

Benjamin Franklin - USA - (1706 - 1790): Experimented with static electricity and identified two types of charges - positive and negative.

Charles Augistin Coulomb - France - (1736 - 1806): Investigated forces between charges using a sensitive torsion balance. He also discovered the inverse square relationship between these forces.

Andre Marie Ampere - France - (1775 - 1836): Investigated forces between currents and developed a meter to measure currents. He distinguished between current and potential difference and studied magnetic fields created by electric currents.

Luigi Galvani - Italy - (1737 - 1798): Discovered the simple cell by use of two different metals in dissecting frogs. Thought the cause of the electricity was animal electricity.

Alessandro Volta - Italy - ( 1745 - 1827): He invented the first battery, the electrophorus and the electroscope. Using two different metals in brine he recreated the cell of Galvani and put several of these in series to form a battery.

Charles Wheatstone - Britain - (1802 - 1875): He invented the concertina, the harmonica, the stereoscope and the wheatstone bridge (an electrical circuit for measuring resistance).

Georg Simon Ohm - Germany - ( 1787 - 1854): Investigated currents flowing through different substances and discovered the relationship between current and potential difference.

Gustav Kirchoff - Germany - (1824 - 1887): Established laws for the flow of electricity in a circuit and showed that electric current travels at the speed of light.

Hans Christian Oersted - Denmark - (1777 - 1851): Discovered the magnetic field around a current carrying conductor.

James Prescott Joule - England -(1818 - 1889) Studied the heating effects of electrical currents flowing through resistors and established the relationship.

Michael Faraday - England - ( 1791 - 1867): Investigated static electricity, developed the electric motor, investigated electrolysis and proposed laws governing the process, discovered electromagnetic induction which paved the way for electrical generators.

Nicholas Callan - Ireland - (1799 - 1864) Developed large electromagnets and batteries, experimented with electromagnetic induction and invented the induction coil.

John Joseph Thomson - England - (1856 - 1940): Experimented with gas discharge tubes. Discovered that "cathode rays" were beams of electrons. He also measured the charge to mass ratio of the electron.

Heinrich Hertz - German - (1821 - 1924): Studied electromagnetic waves, showing that their behaviour was analogous to light and heat waves.

Albert Einstein - German/Swiss - (1879 - 1955): Formulated the theories of relativity and did important work in radiation physics and thermodynamics.

Robert Millikan - USA - (1868 - 1953): Verified experimentally Einstein’s photoelectric Law. Carried out experiments to find the basic unit of electric charge (Millikan’s Oil Drop Experiment).

Max Plank - German - (1858 - 1947): Framed the quantum theory. ( E = hf)

Marie Curie - (Born Marya Sklodovska) - Polish - (1867 - 1934): Discovered the elements radium and polonium and experimented with radioactivity.

Otto Hahn - German - (1879 - 1968): Discovered nuclear fusion (1938).


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