Physics in Action by Topic
Subatomic
Feynman Diagrams: The science of doodling
Every popular explanation of particle physics is liberally illustrated with cartoon-like pictures of straight and wiggly lines representing electrons, photons, and quarks, interacting with one another. These so-called Feynman diagrams were introduced by Richard Feynman in the journal Physical Review in 1949, and they quickly became an essential tool for particle physicists.
Quark-Gluon Plasma
A millionth of a second after the Big Bang, the universe was an incredibly dense plasma, so hot that no nuclei nor even nuclear particles could exist.
Power to the Pentaquark
What’s inside an atom? What’s inside a proton? These are questions asked by physicists, who seek to understand matter on the most fundamental level.
Neutrino Nomads
The neutrino is a ghostly particle that leaves hardly a trace of its passing. Most neutrinos go right through Earth without any deviation or interaction, and trillions harmlessly pierce your body each second.
Neutrino Astrophysics
Very large stars can end their lives in a cataclysmic explosion called a supernova. The photographs show a supernova in the Large Magellanic Cloud, a satellite galaxy of the Milky Way located only about 160,000 light years away.
Fusion Machines
In 1951, the astrophysicist Lyman Spitzer devised a way to contain a hot plasma—an ionized gas—with the hope of producing a sustained fusion reaction that could lead to electric power generation.
Plasma Power
Everyday objects can be classified into solids, liquids, and gases. However, the matter in a lightning bolt, a flame, and the Aurora Borealis are something quite different.
Energetic Degenerates
If systems "seek" the lowest possible energy, why don't atomic electrons all cascade down into the ground state?
The Little Constant that Couldn't?
Physicists measure the values of basic quantities like the speed of light and the charge of the electron. Cosmologists use the results in studies of the origin of the universe, some 12 billion years ago, and they assume the numbers have not changed over this time.
The Buzz about Antimatter
Matter and Antimatter: the cloud chamber track of an electron-positron pair
Water Tubes
Physicists have created a new form of water, one that stays liquid at hundreds of degrees C below zero.
Natural Reactors
The first controlled nuclear reactor, built during World War II, was a great achievement, but it was not the first reactor to operate on planet Earth.
Nuclei Knockdown
At RHIC--the Relativistic Heavy Ion Collider, located at the Brookhaven National Laboratory in New York--gold nuclei traveling at nearly the speed of light smash into each other, destroying themselves and producing a spray of other particles.
AMANDA, Light of my Ice...
An underwater telescope called AMANDA, frozen deep in Antarctic ice, peers down at ghostly neutrinos that pass through Earth from above the Northern Hemisphere.