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When the switch is opend, the voltage ionizes the air between the ends of the switch. Just like a lightning bolt, this ionized air channel conducts the current, which causes the light.
This channel rapidly heats, and the hot air - being less dense - rises, causing the rising, curling flow of electricity
Some time ago, I wrote about the cool properties of corn flour goop - the way it can changes it's behavior between solid and liquid form depending on how fast you hit it. I recently came across this video demonstrating this effect on a grand scale.
On a microscopic level, the corn flour goop consists of small starch particles packed close together. Separating the particles is a thin layer of water that acts like grease – allowing the particles to slide across each other and move around, as long as they move slowly. So, when you slowly push your fingers into the goop, the starch slides out of the way, allowing you to slide in easily. In this situation, the fluid applies viscous drag to the grains gently slowing their motion. However, if you try to smash your fist in quickly, the starch tries to move faster than the water can accommodate and grains come into contact. Now, the much stronger force of static friction acts between the grains – as long as they are being pushed together, there is force preventing them from sliding across each other - and the harder they are pushed together, the stronger the friction force is!
Almost instantly, long columns of starch grains are pushed together – a chain reaction of jammed particles that are held together by the stress you are applying (the force downwards from your hand) and the frictional forces that stop them slipping sideways out from under your hand like they did when you moved slowly. This "jamming" leads to "force chains" through the goop. While the stress is applied these force chains can last essentially forever, because of the static friction. Releasing the stress allows the structures to break down, returning to its fluid-like state.
Gaithersburg, Md.—Raw code for “unbreakable” encryption, based on the principles of quantum physics, has been generated at record speed over optical fiber at the Commerce Department’s National Institute of Standards and Technology (NIST). The work, reported today at the SPIE Defense & Security Symposium in Orlando, Fla., is a step toward using conventional high-speed networks such as broadband Internet and local-area networks to transmit ultra-secure video for applications such as surveillance.
The NIST quantum key distribution (QKD) system uses single photons, the smallest particles of light, in different orientations to produce a continuous binary code, or "key," for encrypting information. The rules of quantum mechanics ensure that anyone intercepting the key is detected, thus providing highly secure key exchange. The laboratory system produced this “raw” key at a rate of more than 4 million bits per second (4 million bps) over 1 kilometer (km) of optical fiber, twice the speed of NIST’s previous record, reported just last month. The system also worked successfully, although more slowly, over 4 km of fiber.
"You are deep underground in a lab that once housed some of the finest minds in chemistry. But robots directed by a crackbrained artificial intelligence have taken it over and plan to use its equipment to destroy the world! After freezing an evil robot with your handy wrist-mounted hot-and-cold gun, you reach the Haber-Bosch room. And now you must correctly synthesize ammonia or die." Critical Mass: The Chemistry Video Game
One of the most famous photos in the history of physics captures the illustrious participants at the fifth Solvay Conference in Brussels, October 1927. 29 physicists, the main quantum theorists of the day, came together, 17 of the 29 attendees were or became Nobel Prize winners. This is a home movie shot by Irving Langmuir, (1932 Nobel Prize winner). Twenty-one of the 29 attendees are on the film. The film includes shots of Erwin Schrödinger, Albert Einstein, Marie Curie, Dirac and Niels Bohr.
