i subscribe to the American Institute of Physic's Physics News Update newsletter. i saw this, and thought you guys might want to see it!
"THE HIGH AND LOW NOTES OF THE UNIVERSE. The Cornell nano-guitar,
first built in 1997 but only now played for the first time, twangs
at a frequency of 40 megahertz, some 17 octaves (or a factor of
130,000) higher than a normal guitar (see figure at
http://www.aip.org/mgr/png/2003/205.htm ). Researchers at Cornell
University used laser light to set the delicate silicon "strings"
(actually slender planks of silicon) of the 10-micron-long guitar in
motion (see figure at
www.aip.org/mgr/png ). There is no practical
microphone available for picking up the guitar sounds, but the
reflected laser light could be computer processed to provide an
equivalent acoustic trace at a much lower frequency. The laser
light could excite more than one string, creating megahertz
"chords." The playing of the nano-guitar will be described by
Lidija Sekaric (now at IBM) at the AVS meeting (paper MM-WeM1;
lidija@us.ibm.com, 914-945-1802;
www.avs.org/symposium/baltimore/default.asp ).
If the nano-guitar's natural tones are among the most high-pitched
sounds in the universe, some of the lowest pitched are to be found
in the vicinity of the black hole in the Perseus galaxy cluster.
The Chandra x-ray telescope recently saw concentric circles in the
inter-galactic gas cloud surrounding the cluster core; some
astronomers interpret the ripples as being sound waves (with a
frequency some 57 octaves below human hearing, and possibly "the
deepest note ever detected from an object in the universe") caused
by jets from the black hole shooting outwards into the nearby
matter.
(
http://chandra.harvard.edu/press/03_...ss_090903.html )"
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Originally Posted by caption from picture
A nanoguitar, devised at Cornell years ago, has been "played" for the first time by shooting laser light at the silicon "strings." The 10-micron long guitar twangs at a frequency of 40 megahertz, some 17 octaves (or a factor of 130,000) higher than a normal guitar.
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also, here.
http://www.aip.org/mgr/png/2003/205.htm
