Croom Physics
Where Physics Can Be Seen Everywhere
| Classical Period | ||
|---|---|---|
| Nicolaus Copernicus | 1473-1543 Polish |
developed a simple heliocentric model of the solar system that explained planetary retrograde motion and overturned Greek astronomy |
| Tycho Brahe | 1546-1601 Danish |
observed a supernova now known as ``Tycho's supernova''; made the most precise observations of stellar and planetary positions then known |
| Johannes Kepler | 1571-1630 German |
established the most exact astronomical tables then known; established the three laws of planetary motion |
| William Gilbert | 1544-1603 English |
hypothesized that the Earth is a giant magnet |
| Galileo Galilei | 1564-1642 Italian |
performed fundamental observations, experiments, and mathematical analyses in astronomy and physics; discovered mountains and craters on the moon, the phases of Venus, and the four largest satellites of Jupiter: Io, Europa, Callisto, and Ganymede |
| Willebrod Snell | 1580-1626 Dutch |
discovered law of refraction (Snell's law) |
| Blaise Pascal | 1623-1662 French |
discovered that pressure applied to an enclosed fluid is transmitted undiminished to every part of the fluid and to the walls of its container (Pascal's principle) |
| Christiaan Huygens | 1629-1695 Dutch |
proposed a simple geometrical wave theory of light, now known as ``Huygen's principle''; pioneered use of the pendulum in clocks |
| Robert Hooke | 1635-1703 English |
discovered Hooke's law of elasticity |
| Sir Isaac Newton | 1643-1727 English |
developed theories of gravitation and mechanics, and invented differential calculus |
| Edmond Halley | 1656-1742 British |
Used his theory of cometary orbits to predict that the comet of 1682 (later named ``Halley's comet'') was periodic |
| Daniel Bernoulli | 1700-1782 Swiss |
developed the fundamental relationship of fluid flow now known as Bernoulli's principle |
| Benjamin Franklin | 1706-1790 American |
the first American physicist; characterized two kinds of electric charge, which he named ``positive'' and ``negative'' |
| Leonard Euler | 1707-1783 Swiss |
made fundamental contributions to fluid dynamics, lunar orbit theory (tides), and mechanics; also contributed prolifically to all areas of classical mathematics |
| Henry Cavendish | 1731-1810 British |
discovered and studied hydrogen; first to measure Newton's gravitational constant; calculated mass and mean density of Earth |
| Charles Augustin de Coulomb | 1736-1806 French |
experiments on elasticity, electricity, and magnetism; established experimentally nature of the force between two charges |
| Joseph-Louis Lagrange | 1736-1813 French |
developed new methods of analytical mechanics |
| James Watt | 1736-1819 Scottish |
invented the modern condensing steam engine and a centrifugal governor |
| Count Alessandro Volta | 1745-1827 Italian |
pioneer in study of electricity; invented the first electric battery |
| Caroline Herschel | 1750-1848 British |
Discovered several comets and was first woman to discover a comet |
| Joseph Fourier | 1768-1830 French |
established the differential equation governing heat diffusion and solved it by devising an infinite series of sines and cosines capable of approximating a wide variety of functions |
| Thomas Young | 1773-1829 British |
studied light and color; known for his double-slit experiment that demonstrated the wave nature of light |
| Jean-Babtiste Biot | 1774-1862 French |
studied polarization of light; co-discovered that intensity of magnetic field set up by a current flowing through a wire varies inversely with the distance from the wire |
| André Marie Ampère | 1775-1836 French |
father of electrodynamics |
| Amadeo Avogadro | 1776-1856 Italian |
developed hypothesis that all gases at same volume, pressure, and temperature contain same number of atoms |
| Johann Carl Friedrich Gauss | 1777-1855 German |
formulated separate electrostatic and electrodynamical laws, including ``Gauss' law''; contributed to development of number theory, differential geometry, potential theory, theory of terrestrial magnetism, and methods of calculating planetary orbits |
| Hans Christian Oersted | 1777-1851 Danish |
discovered that a current in a wire can produce magnetic effects |
| Sir David Brewster | 1781-1868 English |
deduced ``Brewster's law'' giving the angle of incidence that produces reflected light which is completely polarized; invented the kaleidoscope and the stereoscope, and improved the spectroscope |
| Augustin-Jean Fresnel | 1788-1827 French |
studied transverse nature of light waves |
| Georg Ohm | 1789-1854 German |
discovered that current flow is proportional to potential difference and inversely proportional to resistance (Ohm's law) |
| Michael Faraday | 1791-1867 English |
discovered electromagnetic induction and devised first electrical transformer |
| Felix Savart | 1791-1841 French |
co-discovered that intensity of magnetic field set up by a current flowing through a wire varies inversely with the distance from the wire |
| Sadi Carnot | 1796-1832 French |
founded the science of thermodynamics |
| Joseph Henry | 1797-1878 American |
performed extensive fundamental studies of electromagnetic phenomena; devised first practical electric motor |
| Christian Doppler | 1803-1853 Austrian |
experimented with sound waves; derived an expression for the apparent change in wavelength of a wave due to relative motion between the source and observer |
| Wilhelm E. Weber | 1804-1891 German |
developed sensitive magnetometers; worked in electrodynamics and the electrical structure of matter |
| Sir William Hamilton | 1805-1865 Irish |
developed the principle of least action and the Hamiltonian form of classical mechanics |
| James Prescott Joule | 1818-1889 British |
discovered mechanical equivalent of heat |
| Jean-Bernard-Léon Foucault | 1819-1868 French |
accurately measured speed of light; invented the gyroscope; demonstrated the Earth's rotation |
| Sir George Gabriel Stokes | 1819-1903 British |
described the motion of viscous fluids by independently discovering the Navier-Stokes equations of fluid mechanics (or hydrodynamics); developed Stokes theorem by which certain surface integrals may be reduced to line integrals; discovered fluorescence |
| Hermann von Helmholtz | 1821-1894 German |
developed first law of thermodynamics, a statement of conservation of energy |
| Rudolf Clausius | 1822-1888 German |
developed second law of thermodynamics, a statement that the entropy of the Universe always increases |
| Lord Kelvin (born William Thomson) |
1824-1907 British |
proposed absolute temperature scale, of essence to development of thermodynamics |
| Gustav Kirchhoff | 1824-1887 German |
developed three laws of spectral analysis and three rules of electric circuit analysis; also contributed to optics |
| Johann Balmer | 1825-1898 Swiss |
developed empirical formula to describe hydrogen spectrum |
| Sir Joseph Wilson Swan | 1828-1914 British |
developed a carbon-filament incandescent light; patented the carbon process for printing photographs in permanent pigment |
| James Clerk Maxwell | 1831-1879 Scottish |
propounded the theory of electromagnetism; developed the kinetic theory of gases |
| Josef Stefan | 1835-1893 Austrian |
studied blackbody radiation |
| Ernst Mach | 1838-1916 Austrian |
studied conditions that occur when an object moves through a fluid at high speed (the ``Mach number'' gives the ratio of the speed of the object to the speed of sound in the fluid); proposed ``Mach's principle,'' which states that the inertia of an object is due to the interaction between the object and the rest of the universe |
| Josiah Gibbs | 1839-1903 American |
developed chemical thermodynamics; introduced concepts of free energy and chemical potential |
| James Dewar | 1842-1923 British |
liquefied nitrogen and invented the Dewar flask, which is critical for low-temperature work |
| Ludwig Boltzmann | 1844-1906 Austrian |
developed statistical mechanics and applied it to kinetic theory of gases |
| Roland Eötvös | 1848-1919 Hungarian |
demonstrated equivalence of gravitational and inertial mass |
| Oliver Heaviside | 1850-1925 English |
contributed to the development of electromagnetism; introduced operational calculus and invented the modern notation for vector calculus; predicted existence of the Heaviside layer (a layer of the Earth's ionosphere) |
| George Francis FitzGerald | 1851-1901 Irish |
hypothesized foreshortening of moving bodies (Lorentz-FitzGerald contraction) to explain the result of the Michelson-Morley experiment |
| Janne Rydberg | 1854-1919 Swedish |
analyzed the spectra of many elements; discovered many line series were described by a formula that depended on a universal constant (the Rydberg constant) |
| Edwin H. Hall | 1855-1938 American |
discovered the ``Hall effect,'' which occurs when charge carriers moving through a material are deflected because of an applied magnetic field - the deflection results in a potential difference across the side of the material that is transverse to both the magnetic field and the current direction |
| Heinrich Hertz | 1857-1894 German |
worked on electromagnetic phenomena; discovered radio waves and the photoelectric effect |
| Nikola Tesla | 1857-1943 Serbian-born American |
created alternating current |
| Nobel Laureates | ||
| Johannes van der Waals | 1837-1923 Dutch |
worked on equations of state for gases and liquids |
| Lord Rayleigh (born John William Strutt) |
1842-1919 British |
discovered argon; explained how light scattering is responsible for red color of sunset and blue color of sky |
| Albert A. Michelson | 1852-1931 German-born American |
devised an interferometer and used it to try to measure Earth's absolute motion; precisely measured speed of light |
| Hendrik Antoon Lorentz | 1853-1928 Dutch |
introduced Lorentz transformation equations of special relativity; advanced ideas of relativistic length contraction and relativistic mass increase; contributed to theory of electromagnetism |
| Sir Joseph John Thomson | 1856-1940 British |
demonstrated existence of the electron |
| Max Planck | 1858-1947 German |
formulated the quantum theory; explained wavelength distribution of blackbody radiation |
| Pierre Curie | 1859-1906 French |
studied radioactivity with wife, Marie Curie; discovered piezoelectricity |
| Marie Curie | 1867-1934 Polish-born French |
discovered radioactivity of thorium; co-discovered radium and polonium |
| Robert Millikan | 1868-1953 American |
measured the charge of an electron; introduced term ``cosmic rays'' for the radiation coming from outer space; studied the photoelectric effect |
| Lord Ernest Rutherford | 1871-1937 New Zealander |
theorized existence of the atomic nucleus based on results of the alpha-scattering experiment performed by Hans Geiger and Ernest Marsden; developed theory of Rutherford scattering (scattering of spinless, point-like particles from a Coulomb potential) |
| Guglielmo Marconi | 1874-1937 Italian |
invented the first practical system of wireless telegraphy |
| Johannes Stark | 1874-1957 German |
discovered splitting of spectral lines in a strong electric field |
| Charles Glover Barkla | 1877-1944 British |
discovered that every chemical element, when irradiated by x rays, can emit an x-ray spectrum of two line-groups, which he named the K-series and L-series, that are of fundamental importance to understanding atomic structure |
| Albert Einstein | 1879-1955 German-born American |
explained Brownian motion and photoelectric effect; contributed to theory of atomic spectra; formulated theories of special and general relativity |
| Otto Hahn | 1879-1968 German |
discovered the fission of heavy nuclei |
| Niels Bohr | 1885-1962 Danish |
contributed to quantum theory and to theory of nuclear reactions and nuclear fission |
| Gustav Hertz | 1887-1975 German |
experimentally confirmed that atomic energy states are quantized |
| Erwin Schrödinger | 1887-1961 Austrian |
contributed to creation of quantum mechanics; formulated the Schrödinger wave equation |
| Sir James Chadwick | 1891-1974 British |
discovered the neutron |
| Sir Edward Appleton | 1892-1965 English |
discovered the layer of the Earth's atmosphere, called the Appleton layer, which is the part of the ionosphere having the highest concentration of free electrons and is the most useful for radio transmission |
| Prince Louis-Victor de Broglie | 1892-1987 French |
predicted wave properties of the electron |
| Arthur Compton | 1892-1962 American |
discovered the increase in wavelength of x rays when scattered by an electron |
| Robert S. Mulliken | 1896-1986 American |
introduced the theoretical concept of the molecular orbital, which led to a new understanding of the chemical bond and the electronic structure of molecules |
| Wolfgang Pauli | 1900-1958 Austrian-born American |
discovered the exclusion principle; suggested the existence of the neutrino |
| Enrico Fermi | 1901-1954 Italian-born American |
performed experiments leading to first self-sustaining nuclear chain reaction; developed a theory of beta decay that introduced the weak interaction; derived the statistical properties of gases that obey the Pauli exclusion principle |
| Werner Heisenberg | 1901-1976 German |
contributed to creation of quantum mechanics; introduced the ``uncertainty principle'' and the concept of exchange forces |
| Ernest Orlando Lawrence | 1901-1958 American |
invented the cyclotron |
| Paul Adrien Maurice Dirac | 1902-1984 British |
helped found quantum electrodynamics; predicted the existence of antimatter by combining quantum mechanics with special relativity |
| Ernest Walton | 1903-1995 Irish |
co-invented the first particle accelerator |
| Ernst Ruska | 1906-1988 German |
designed the first electron microscope |
| William Shockley | 1910-1989 American |
co-discovered the transistor effect |
| William Fowler | 1911-1995 American |
studied nuclear reactions of astrophysical significance; developed, with others, a theory of the formation of chemical elements in the universe |
| Glenn T. Seaborg | 1912-1999 American |
co-discovered plutonium and all further transuranium elements through element 102 |
| Richard P. Feynman | 1918-1988 American |
co-developed quantum electrodynamics; created a new formalism for practical calculations by introducing a graphical method called Feynman diagrams |
| K. Alexander Müller | 1927- Swiss |
co-discovered the first ceramic superconductors |
| Others | ||
| George E. Hale | 1868-1938 American |
revolutionized spectral observations by inventing and using the spectroheliograph; discovered magnetic fields in sunspots; first astronomer to be officially called an astrophysicist; founded the Yerkes, Mt. Wilson, and Palomar Observatories |
| Walther Meissner | 1882-1974 German |
co-discovered the ``Meissner effect'', whereby a superconductor expells a magnetic field |
| Hans Geiger | 1883-1945 German |
helped measure charge-to-mass ratio for alpha particles; invented Geiger counter for detecting ionizing particles |
| Edwin Hubble | 1889-1953 American |
first to measure distance to the Andromeda nebula, establishing it to be a separate galaxy; later measured distances to other galaxies and discovered that they recede at a rate proportional to their distance (Hubble's law) |
| Sir Robert Watson-Watt | 1892-1973 Scottish |
developed radar |
| Charles Francis Richter | 1900-1985 American |
established the Richter scale for the measurement of earthquake intensity |
| Robert J. Van de Graaf | 1901-1967 American |
invented the Van de Graaf electrostatic generator |
| J. Robert Oppenheimer | 1904-1967 American |
headed Manhattan Project to develop the nuclear fission bomb |
| Sir Rudolf Peierls | 1907-1995 German-born British |
many contributions in theoretical physics, including an improved calculation of the critical mass needed to make a fission bomb |
| Edward Teller | 1908-2003 Hungarian-born American |
helped develop atomic and hydrogen bombs |
| Peter Higgs | 1929- British |
proposed with others the Higgs mechanism by which particles are endowed with mass by interacting with the Higgs field, which is carried by Higgs bosons |
| T. Kenneth Fowler | 1931- American |
contributed to the theory of plasma physics and magnetic fusion |
| Carl Sagan | 1934-1996 American |
was a leader in the search for extraterrestrial intelligence; contributed to most of the space missions to explore Mars and the outer planets; warned that all-out nuclear war could lead to a ``nuclear winter'' |
| Stephen W. Hawking | 1942- British |
combined general relativity with quantum theory to predict that black holes should emit radiation and evaporate. |
| Michio Kaku | 1947- American |
The co-founder of string field theory. |
| Neil deGrasse Tyson | 1958- American |
Is an American astrophysicist, a science communicator, the Frederick P. Rose Director of the Hayden Planetarium at the Rose Center for Earth and Space, and a Research Associate in the Department of Astrophysics at the American Museum of Natural History. |
| Stephen Wolfram | 1959- British |
created Mathematica, the first modern computer algebra system; contributed to development of complexity theory |
| Brian Greene | 1963- American |
String Theorist |
