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PHYSICS NEWS UPDATE
The American Institute of Physics Bulletin of Physics News
Number 602
August 30, 2002
By Phillip F. Schewe, Ben Stein, and James Riordon

DNA Lasers

A DNA laser has been demonstrated by scientists at the Chitose Institute of Science and Technology in Japan who have expanded on the idea of dye lasers, in which light-emitting dye molecules (of which there are many, offering a welcome versatility in tuning the output laser wavelength) are embedded in a surrounding matrix material. Putting too many dye molecules close together, however, can lead to the quenching of the fluorescence. In DNA this problem is greatly decreased since the dye molecules can be lodged (intercalated) in the double strand scaffold of the DNA structure. It is too early to talk of such optimal properties as emittance or energy efficiency, but the researchers believe that because they have achieved thin-film lasing with such a high dye concentration then the engineering of compact, tunable lasers will follow.
(Kawabe et al., Applied Physics Letters, 19 August; contact Yutaka Kawabe; see figure at http://www.aip.org/mgr/png/)
(Source)

Glow-in-the-dark tattoos??

Pointlike and "Extended" Dark Matter
Distinguishing between pointlike and "extended" dark matter will be possible in new experiments. Detecting the elusive dark matter that seems to pervade the universe is difficult enough, but it's an even bigger challenge to distinguish between the different kinds of the invisible matter.

Candidates for dark matter include pointlike particles such as neutralinos (predicted by supersymmetry theory) and extended objects such as "Q-balls," large bags of particles such as squarks and sleptons which are also predicted in supersymmetry. Numerous planned and ongoing experiments aim to detect directly dark matter, which is believed to possess energies in the minuscule range of 0.001-0.01 MeV.
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“New Wave”?
A new kind of ocean wave has been discovered by geophysicists in the US and Mexico (Rhett Butler, IRIS Consortium, and Cinna Lomnitz, UNAM).

At the Hawaii-2 Observatory, an unmanned research laboratory sitting on the seafloor between Hawaii and California, ocean waves of many varieties are observed.

Some are acoustic waves, underwater cousins of sound waves in the air, and consisting of pressure waves that alternately expand and compress water as they propagate through the ocean at the speed of sound in water.

Others are Rayleigh waves, seismic waves that propagates near the surface of the earth. Triggered by earthquakes, Rayleigh waves propagate as horizontal and vertical motions in the sediments and underlying crust.
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