February 19, 2007
Below you will find a brief
excerpt from DISCOVER Magazine's Top 100 Scientific discoveries
of 2006, with Dr. Boyd's story in 87th place as one of
the "The Top 6 Physics
Stories of 2006":
" Light Moves in Reverse
Physicists at the University of Rochester have coaxed
light into traveling backward-and, weirdly enough, to
do so faster than light itself. In a clever tabletop experiment,
the researchers sent a pulse of light through a single
optical fiber doped with erbium, a metal that alters the
speed at which light waves move through the fiber. Just
as one light pulse enters, a second pulse appears at the
opposite end, as if by magic. This second pulse then splits
in two, with half propagating backward and the other half
exiting the fiber. The overall effect is that "the
pulse appears to leave before it enters," says physicist
Robert Boyd, who designed the experiment. No physical
laws are violated because the information in the pulse
never breaks the light-speed barrier. In recent years
physicists have also learned to slow light or to ramp
it up past the usual speed of 186,282 miles per second.
Confused? This animated Web site may help. Replacing electrical
switches with optical buffers that control the speed of
light could lead to more efficient high-speed telecommunication
networks. "
Alex Stone
For the complete listing of the top 100
stories, please click here.
©2007 University of
Rochester
