About 18 months ago, we ran a story entitled How Our Ancestors Used to Sleep Twice a Night and Highlighting the Problem of Present Shock. The author, Jeremy D. Johnson, informed us that, “8 hour sleeping is a modern invention” and in the 18th Century “we slept twice a night, getting up for an hour or two for recreation before heading back to bed until dawn.” Now San Francisco’s public television station KQED has produced a short film laying the blame on artificial light:
Tag Archives | Light
Light sabers are now a reality, ScienceDaily reports:
… Read the rest
A group at the Harvard-MIT Center for Ultracold Atoms have managed to coax light photons into binding together to form molecules — a state of matter that, until recently, had been purely theoretical.
The discovery runs contrary to accepted wisdom about the nature of light. Photons have long been described as massless particles which don’t interact with each other. “Photonic molecules,” however, behave more like something in science fiction — the light saber.
“What we have done is create a special type of medium in which photons interact with each other so strongly that they begin to act as though they have mass, and they bind together to form molecules,” Lukin said.
The system could be useful in classical computing, considering the power-dissipation challenges chip-makers now face. It might one day even be used to create complex three-dimensional structures wholly out of light.
Via Quora, how, with a couple dollars and a few spare minutes, to make yourself invisible to Big Brother:
… Read the rest
Most cameras (especially black and white security cameras) will see low levels of infrared light. This helps them video at dusk/dawn and in lower levels of light. To test this theory turn on your video camera and point your TV remote control at it. Change a few channels and you will see a pulse of light flash that the naked eye obviously can’t see.
With that said you can easily make an infrared hat with cheap $1 infrared LEDs stitched into the front of the hat, the more the better… Attach a 9 volt battery to the LEDS and bam you are now a giant LED flash light. People will see nothing out of the ordinary, but CCTV cameras will only see a large flash of infrared light coming from your head, hiding your face.
Commuters in the northern Swedish town of Umea are being treated to ultra-violet light therapy as the long, dark winter for which the Nordic state is renowned draws in. Energy company Umea Energi has decided to install ultra-violet lights at about 30 bus stops for people, which will be in place for the next three weeks. "This is so people can get a little energy kick as they are waiting," said Umea Energi marketing chief Anna Norrgard. Umea is about 600 km north of capital city Stockholm...
Between 1957 and 1959, Belson collaborated with composer Henry Jacobs on the historic Vortex Concerts, which combined electronic music with moving visual abstractions projected on the dome of Morrison Planetarium in San Francisco (and also the Brussels World Fair in 1958). These pioneer Light Shows used filmed imagery as well as multiple projections of geometric and polymorphous light phenomena. The Vortex experience inspired Belson to abandon traditional painting and animation in favor of creating visual phenomena in something like real time, by live manipulation of pure light. Many of the films share certain images which Belson regards as "hieroglyphic-ideographic" visual units that express complex ideation not easily stated in verbal terms.
A simulated sunset from a foreign solar system — what a dreamy dusk. PhysOrg writes:
… Read the rest
Professor Frederic Pont, of the University of Exeter, imagined what it might really look like if a person were able to visit another planet and to then sit quietly watching as the sun set. He used data from a camera onboard Hubble, knowledge of how the color of light changes based on chemicals it encounters, and computer modeling, to create an actual image of what a sunset on an actual planet far out in space would look like. The planet in question, exoplanet HD209458b, nicknamed Osiris, just happens to be quite large and circles its star rather closely.
Though we couldn’t technically sit on the surface of Osiris, since it doesn’t have one, the picture that Pont produced approximates what it would look like, and the results are truly beautiful. The light from Osiris’s star is white, like our own sun, but when it passes through the sodium in Osirisi’s atmosphere, red light in it is absorbed, leaving the starlight to appear blue.
There’s always something, says a Swedish study. Phenomenica reports:
… Read the rest
Scientists claim to have produced particles of light out of vacuum, proving that space is not empty.
An international team says that its ingenious experiment in which tiny parcels of light, or photons, are produced out of empty space has confirmed that a vacuum contains quantum fluctuations of energy, the ‘Nature’ journal reported.
In fact, the scientists have demonstrated for the first time a strange phenomenon known as the dynamical Casimir effect, or DCE for short.
The DCE involves stimulating the vacuum to shed some of the myriad “virtual” particles that fleet in and out of existence, making them real and detectable. Moreover, the real photons produced by the DCE in their experiment collectively retain a peculiar quantum signature that ordinary light lacks.
The research, led by Chris Wilson of Chalmers University of Technology in Sweden, shows that a related dynamic effect can occur when such a mirror moves very fast through the vacuum.
No, the above is not an exaggeration. I’m fine with nixing flying hovercars so long as we get this. Discovery writes:
The researchers report that they were able to create bright laser pulses that lasted a few nanoseconds with a single cell. Amazingly the cells were not damaged during the production of the laser light but were able to withstand hundreds of pulses.
The project took place at the Wellman Center for Photomedicine in Massachusetts. The key to this breakthrough involved the use of the widely studied protein known as green fluorescent protein. This protein, which was first discovered in jellyfish, has (as the name implies) the property of generating light.
Although there are no immediate plans to use this technology, the erosion of the barrier between optical technologies and biology could open many doors in therapy and research.
I’ve seen the most interesting thing on TV a thousand times, but never noticed it. Artist Stephan Tillmans photographs tube televisions at the split second they are turned off, to glorious effect. Via his website:
The television picture breaks down and creates a structure of light. The pictures refuse external reference and broach the issue of the difference between abstraction and concretion in photography.
Australian scientists have built device that generates a tractor beam, commonly considered a figment of alien abduction scenarios and Star Trek. The researchers’ creation thus far is capable of transporting small objects distances of up to five feet, using only a beam of light, Popular Science reports:
… Read the rest
Using only light, Australian researchers say they are able to move small particles almost five feet through the air. It’s more than 100 times the distance achieved by existing optical “tweezers,” the researchers say.
Not quite a simple grabby tractor beam, the new system works by shining a hollow laser beam at an object and taking advantage of air-temperature differences to move it around.
It works by shining a hollow laser beam around small glass particles, as Inside Science explains. The air around the particle heats up, but the hollow center of the beam stays cool. The heated air molecules keep the object balanced in the dark center.