Showing posts with label Light. Show all posts
Showing posts with label Light. Show all posts

Sunday, February 02, 2014

Autumn Light

Photograph Autumn Light by Peter From on 500px

In the depth a light will grow,
A silver shine no shadows know,
Like wings unfolding in the sky,
That circle ’round a gleaming eye,
Turning darkness all away,
Even depths will know their day,
For every shadow has its end,
In light!
Life will return again!
By: Peter From
Quote by: Robert Fanney
Quote provided by: CZ

Thursday, August 09, 2012

Using BEC To Slow Down Light



By use of a Bose--Einstein Condensate, Danish physicist Lene Vestergaard Hau (Harvard University) succeeded in slowing a beam of light to about 17 metres per second, and, in 2001, was able to momentarily stop a beam.

About a decade ago, Hau started playing with BECs — for a physicist, that means shooting lasers at them. She found that lasers of the right wavelengths could tune the optical properties of a BEC, giving Hau an almost supernatural command over any other light shined into it. 

Her first trick was slowing a pulse of light to a crawl — 15 mph as it traveled through the BEC. Since then, Hau has completely frozen a pulse and then released it. And recently she shot a pulse into one BEC and stopped it — turning the BEC into a hologram, a sort of matter version of the pulse. Then she transferred that matter waveform into an entirely different BEC nearby — which emitted the original light pulse. That's just freaky. 



Hey, Einstein may have set that initial speed limit of light, but he only theorized about BECs. "It's not breaking relativity," Hau says. "But I'm sure he would have been rather surprised."