These are Good articles, which meet a core set of high editorial standards.
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Image 1Joseph Sidney Gelders (November 20, 1898 – March 1, 1950) was an American physicist who later became an
antiracist,
civil rights activist,
labor organizer, and communist. In the mid-1930s, he served as the secretary and southern-U.S. representative of the
National Committee for the Defense of Political Prisoners. In September 1936, Gelders was kidnapped, beaten, and nearly killed by members of the
Ku Klux Klan for his civil rights and labor organizing activities. After his recovery, Gelders continued his activism and cofounded the
Southern Conference for Human Welfare and the
National Committee to Abolish the Poll Tax. He collaborated closely with other activists including
Lucy Randolph Mason and
Virginia Foster Durr. Internal injuries sustained during his kidnapping and assault led to Gelders' death on March 1, 1950. (
Full article...)
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Image 2Charles Allen Thomas (February 15, 1900 – March 29, 1982) was a noted American chemist and businessman, and an important figure in the
Manhattan Project. He held over 100 patents.
A graduate of
Transylvania College and
Massachusetts Institute of Technology, Thomas worked as a research chemist at
General Motors as part of a team researching
antiknock agents. This led to the development of
tetraethyllead, which was widely used in motor fuels for many decades until its toxicity led to its prohibition. In 1926, he and Carroll A. "Ted" Hochwalt co-founded Thomas & Hochwalt Laboratories in
Dayton, Ohio, with Thomas as president of the company. It was acquired by
Monsanto in 1936, and Thomas would spend the rest of his career with Monsanto, rising to become its president in 1950, and chairman of the board from 1960 to 1965. He researched the chemistry of
hydrocarbons and
polymers, and developed the proton theory of
aluminium chloride, which helped explain a variety of chemical reactions, publishing a book on the subject in 1941. (
Full article...)
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Image 4
Bradner's identification badge photo from Los Alamos
(November 5, 1915 – May 5, 2008) was an American
physicist at the
University of California who is credited with inventing the
neoprene wetsuit, which helped to revolutionize
scuba diving and
surfing.
A graduate of Ohio's
Miami University, he received his doctorate from
California Institute of Technology in
Pasadena, California, in 1941. He worked at the
US Naval Ordnance Laboratory during
World War II, where he researched
naval mines. In 1943, he was recruited by
Robert Oppenheimer to join the
Manhattan Project at the
Los Alamos Laboratory. There, he worked with scientists including
Luis Alvarez,
John von Neumann and
George Kistiakowsky on the development of the
high explosives and
exploding-bridgewire detonators required by
atomic bombs. (
Full article...)
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Image 5Charles Louis Critchfield (June 7, 1910 – February 12, 1994) was an American
mathematical physicist. A graduate of
George Washington University, where he earned his PhD in physics under the direction of
Edward Teller in 1939, he conducted research in
ballistics at the
Institute for Advanced Study in
Princeton and the
Ballistic Research Laboratory at the
Aberdeen Proving Ground, and received three patents for improved
sabot designs.
In 1943, Teller and
Robert Oppenheimer persuaded Critchfield to come to the
Manhattan Project's
Los Alamos National Laboratory, where he joined the Ordnance Division under
Captain William Parsons on the
gun-type fission weapons,
Little Boy and
Thin Man. After it was discovered that the Thin Man design would not work, he was transferred to
Robert Bacher's Gadget Division as the leader of the Initiator group, which was responsible for the design and testing of the
"Urchin" neutron initiator that provided the burst of neutrons that kick-started the nuclear detonation of the
Fat Man weapon. (
Full article...)
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Image 7Floating Clouds (sometimes called
Flying Saucers by the artist) is a work of art by American sculptor
Alexander Calder, located in the
Aula Magna of the
University City of Caracas in
Venezuela. The 1953 work comprises many 'cloud' panels that are renowned both artistically and acoustically. The piece is seen as "one of Calder's most truly monumental works" and the prime example of the urban-artistic theory of campus architect
Carlos Raúl Villanueva.
Originally intended as only an art piece, the panels were moved inside the Aula Magna to resolve the poor acoustics caused by the hall's design; the hall has since been said to have some of the best acoustics in the world. The
Floating Clouds are named specifically in the
UNESCO listing of the campus as a
World Heritage Site, and are greatly renowned in Venezuela. (
Full article...)
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Image 10The
universe comprises all of
existence: all forms of
matter and
energy, and the structures they form, from
sub-atomic particles to entire
galactic filaments. Since the early 20th century, the field of
cosmology establishes that
space and time emerged together at the
Big Bang 13.787±0.020 billion years ago and that the
universe has been expanding since then. The
portion of the universe that can be seen by humans is approximately 93 billion
light-years in diameter at present, but the total size of the universe is not known.
Some of the earliest
cosmological models of the universe were
geocentric, placing Earth at the center. During the European
Scientific Revolution, astronomical observations led to
a heliocentric model. Further observational improvements led to the realization that the Sun is one of a few hundred billion stars in the
Milky Way, which is one of a few hundred billion galaxies in the observable universe. Many of the stars in a galaxy
have planets.
At the largest scale, galaxies are distributed uniformly and the same in all directions, meaning that the universe has neither an edge nor a center. At smaller scales, galaxies are distributed in
clusters and
superclusters, which form immense filaments and
voids in space, creating a vast foam-like structure. Discoveries in the early 20th century lead to the Big Bang theory with a hot fireball, cooling and becoming less dense as the universe expanded, allowing the first
subatomic particles and simple
atoms to form. Giant clouds of
hydrogen and
helium were gradually drawn to the places where matter was most
dense, forming the first galaxies, stars, and everything else seen today. (
Full article...)
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Image 11A
gravity bong, also known as a GB, bucket bong, grav, geeb, gibby, yoin, or ghetto bong, is a method of consuming smokable substances such as
cannabis. The term describes both a
bucket bong and a
waterfall bong, since both use air pressure and water to draw smoke. A
lung uses similar equipment but instead of water draws the smoke by removing a compacted plastic bag or similar from the chamber.
The bucket bong is made out of two containers, with the larger, open-top container filled with water. The smaller has an attached
bowl and open bottom, and the smaller is placed into the larger. Once the bowl is lit, the operator must move the small container up, causing a pressure difference. Smoke slowly fills the small jar until the user removes the bowl and inhales the contents. A waterfall bong is made up of only one container. The container must have a bowl and a small hole near the base so the water can drain easily. As the water flows out of the container, air is forced through the bowl and causes the substance to burn and accumulate smoke in the bong. (
Full article...)
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Image 12Ancient, medieval and
Renaissance astronomers and philosophers developed many different theories about the
dynamics of the celestial spheres. They explained the motions of the various
nested spheres in terms of the materials of which they were made, external movers such as celestial intelligences, and internal movers such as motive souls or impressed forces. Most of these models were qualitative, although a few of them incorporated quantitative analyses that related speed, motive force and resistance. (
Full article...)
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Image 13A
waterspout is a rotating column of air that occurs over a
body of water, usually appearing as a
funnel-shaped cloud in contact with the water and a
cumuliform cloud. There are
two types of waterspout, each formed by distinct mechanisms. The most common type is a weak vortex known as a "fair weather" or "non-tornadic" waterspout. The other less common type is simply a classic
tornado occurring over water rather than land, known as a "tornadic", "supercellular", or "mesocyclonic" waterspout, and accurately a "tornado over water". A fair weather waterspout has a five-part life cycle: formation of a dark spot on the water surface; spiral pattern on the water surface; formation of a spray ring; development of a visible
condensation funnel; and ultimately, decay. Most waterspouts do not suck up water.
While waterspouts form mostly in
tropical and
subtropical areas, they are also reported in
Europe,
Western Asia (the Middle East),
Australia,
New Zealand, the
Great Lakes,
Antarctica, and on rare occasions, the
Great Salt Lake. Some are also found on the East Coast of the United States, and the coast of California. Although rare, waterspouts have been observed in connection with
lake-effect snow precipitation bands. (
Full article...)
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Image 14
Vice Admiral John T. Hayward
(15 November 1908 – 23 May 1999) was an American
naval aviator during
World War II. He helped develop one of the two
atomic bombs that was
dropped on Japan in the closing days of the war. Later, he was a pioneer in the development of
nuclear propulsion, nuclear weapons, guidance systems for ground- and air-launched rockets, and underwater
anti-submarine weapons. A former
batboy for the
New York Yankees, Hayward dropped out of high school and lied about his age to enlist in the
United States Navy at age 16. He was subsequently admitted to the
United States Naval Academy at Annapolis, from which he graduated 51st in his class of 1930. He volunteered for naval aviation.
During World War II, he served at the
Naval Aircraft Factory in Philadelphia, where he was involved in an effort to improve aircraft instrumentation, notably the compass and altimeter. He attended the
University of Pennsylvania's
Moore School of Electrical Engineering, and studied nuclear physics. In June 1942, he assumed command of a new patrol bomber squadron, VB-106, equipped with
PB4Y-1 Liberators, which he led in a daring raid on
Wake Island, in the
Solomon Islands campaign, and in the
Southwest Pacific Area. Returning to the United States in 1944, he was posted to the
Naval Ordnance Test Station at Inyokern, California, where he joined the
Manhattan Project, participating in
Project Camel, the development of the non-nuclear components of the
Fat Man bomb, and in its drop testing. (
Full article...)
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Image 15The
Lorentz group is a
Lie group of symmetries of the
spacetime of
special relativity. This group can be realized as a collection of
matrices,
linear transformations, or
unitary operators on some
Hilbert space; it has a variety of
representations. This group is significant because special relativity together with
quantum mechanics are the two physical theories that are most thoroughly established, and the conjunction of these two theories is the study of the infinite-dimensional unitary representations of the Lorentz group. These have both historical importance in mainstream physics, as well as connections to more speculative present-day theories.
The development of the representation theory has historically followed the development of the more general theory of representation theory of
semisimple groups, largely due to
Élie Cartan and
Hermann Weyl, but the Lorentz group has also received special attention due to its importance in physics. Notable contributors are physicist
E. P. Wigner and mathematician
Valentine Bargmann with their
Bargmann–Wigner program, one conclusion of which is, roughly,
a classification of all unitary representations of the inhomogeneous Lorentz group amounts to a classification of all possible relativistic wave equations. The classification of the irreducible infinite-dimensional representations of the Lorentz group was established by
Paul Dirac's doctoral student in theoretical physics,
Harish-Chandra, later turned mathematician, in 1947. Closely related work was published independently by Bargmann and
Israel Gelfand together with
Mark Naimark in the same year. (
Full article...)
The following are images from various physics-related articles on Wikipedia.
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Image 1Johannes Kepler's first
law of planetary motion states that planets move in elliptical orbits about the Sun. (from
History of physics)
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Image 3The
quantum Hall effect: Components of the Hall resistivity as a function of the external magnetic field (from
Condensed matter physics)
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Image 4Classical physics is usually concerned with everyday conditions: speeds are much lower than the
speed of light, sizes are much greater than that of atoms, yet very small in astronomical terms. Modern physics, however, is concerned with high velocities, small distances, and very large energies. (from
Modern physics)
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Image 6One possible signature of a Higgs boson from a simulated
proton–proton collision. It decays almost immediately into two jets of
hadrons and two electrons, visible as lines. (from
History of physics)
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Image 9James Prescott Joule's apparatus for measuring the
mechanical equivalent of heat which the "
work" of the falling weight is converted into the "
heat" of agitation in the water. (from
History of physics)
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Image 11The ancient Greek mathematician
Archimedes, developer of ideas regarding
fluid mechanics and
buoyancy. (from
History of physics)
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Image 12Marie Skłodowska-Curie(1867–1934) received Nobel prizes in physics (1903) and chemistry (1911). (from
History of physics)
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Image 13Computer simulation of
nanogears made of
fullerene molecules. It is hoped that advances in nanoscience will lead to machines working on the molecular scale. (from
Condensed matter physics)
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Image 14Magdeburg hemispheres, an experiment by
Otto von Guericke where two metal hemispheres are held together by vacuum and cannot be separated even if large forces are applied. (from
History of physics)
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Image 16Galileo Galilei (1564–1642), early proponent of the modern scientific worldview and method (from
History of physics)
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Image 17Classical physics (
Rayleigh–Jeans law, black line) failed to explain
black-body radiation – the so-called
ultraviolet catastrophe. The quantum description (
Planck's law, colored lines) is said to be
modern physics. (from
Modern physics)
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Image 18Sir Isaac Newton (1642–1727) (from
History of physics)
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Image 19Chien-Shiung Wu worked on parity violation in 1956 and announced her results in January 1957. (from
History of physics)
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Image 21The Hindu-Arabic numeral system. The inscriptions on the
edicts of Ashoka (3rd century BCE) display this number system being used by the Imperial
Mauryas. (from
History of physics)
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Image 22Christiaan Huygens (1629–1695) (from
History of physics)
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Image 23Composite montage comparing
Jupiter (
left) and its four
Galilean moons (
from top:
Io,
Europa,
Ganymede,
Callisto) (from
History of physics)
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Image 24Image of X-ray diffraction pattern from a
protein crystal (from
Condensed matter physics)
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Image 25Maxwell's demon, thought experiment by
James Clerk Maxwell to describe the
kinetic theory of gases and describe how a microscopic creature could lead to violations of the
second law of thermodynamics. (from
History of physics)
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Image 27Star maps by the 11th century Chinese
polymath Su Song are the oldest known
woodblock-printed star maps to have survived to the present day. This example, dated 1092, employs the cylindrical
equirectangular projection. (from
History of physics)
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Image 28Hydrogen
emission spectrum is discrete (here in log scale). The lines can only be explained with quantum mechanics. (from
History of physics)
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Image 29Einstein proposed that
gravitation results from
masses (or their equivalent energies)
curving ("bending") the
spacetime in which they exist, altering the paths they follow within it. (from
History of physics)
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Image 30The
Voltaic pile, the first battery was invented by
Alessandro Volta in 1800 (from
History of physics)
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Image 31Richard Feynman's Los Alamos ID badge (from
History of physics)
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Image 32A
magnet levitating above a
high-temperature superconductor. Today some physicists are working to understand high-temperature superconductivity using the AdS/CFT correspondence. (from
Condensed matter physics)
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Image 33Replica of
William Herschel's telescope used to discover
Uranus (from
History of physics)
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Image 36The first
Bose–Einstein condensate observed in a gas of ultracold
rubidium atoms. The blue and white areas represent higher density. (from
Condensed matter physics)
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Image 37Newton's cannonball, a though experiment by Newton relating the motion of a projectile and orbiting of planets. (from
History of physics)
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Image 38Albert Einstein (1879–1955), ca. 1905 (from
History of physics)
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Image 39Crookes tube used to study
cathode rays. It led to the discovery of the
electron by
J. J. Thomson. (from
History of physics)
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Image 40A
Feynman diagram representing (left to right) the production of a photon (blue
sine wave) from the
annihilation of an electron and its complementary
antiparticle, the
positron. The photon becomes a
quark–
antiquark pair and a
gluon (green spiral) is released. (from
History of physics)
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