I have been noting for some years now that everything my grade 3 teacher taught us was wrong: For example, I clearly remember her laughing at me when I pointed out that the bump on Africa seemed to fit into the corner of South America and telling me that, "the continents don't move, silly!" Then along came plate techtonics. Or the time she explained atoms were the smallest things and laughing when I asked what they were made out of. She had apparently never heard of quarks, though she really should have been. And etc. But I must confess that as the list of things I was taught and have always believed true but now turn out to be wrong, grows longer, it is starting to bug me.
Here the latest brain hurting discovery: A team of researchers headed by Lene Hau has found a way to slow the speed of light to a complete stop, and then restart it. Previously, Lau and her colleagues reduced the speed of light to 38 miles per hour (the speed of suburban traffic) -- Nature 397: 594 (1999).
- NASA-funded research at Harvard University, Cambridge, Mass., that literally stops light in its tracks, may someday lead to breakneck-speed computers that shelter enormous amounts of data from hackers. ..."This could open up a whole new way to use light, doing things we could only imagine before," Hau said. "Until now, many technologies have been limited by the speed at which light travels." The speed of light is approximately 186,000 miles per second (670 million miles per hour). ... Hau's team accomplished "light magic" by laser-cooling a cigar-shaped cloud of sodium atoms to one-billionth of a degree above absolute zero, the point where scientists believe no further cooling can occur. Using a powerful electromagnet, the researchers suspended the cloud in an ultra-high vacuum chamber, until it formed a frigid, swamp-like goop of atoms.When they shot a light pulse into the cloud, it bogged down, slowed dramatically, eventually stopped, and turned off. The scientists later revived the light pulse and restored its normal speed by shooting an additional laser beam into the cloud.
As a long time science fiction reader, the news release immediately brought to mind the Bob Shaw "slow glass" stories, in which windows made of slow glass show scenes that were on the other side of them years before. See, for example, Light of Other Days.
And to think my elementary school teachers did not approve of SF. In the long run, SF has proved more often right than they were!
I wasn't sure how I felt about the "frozen light" news release, though, until I read Dennis Valdron's reaction:
- Bugger this. Whatever happened to the good old days when the Universe was
not accelerating, there were only four fundamental forces and you damned
well knew where you stood with the speed of light. Goddamn kids, mucking
around with universal constants like the gain on their stereo system. Mark
my words, no good will come of this physics hooliganism!
Seems to about capture it for me!
