From: J Corbally (icorb@indigo.ie)
Date: Thu Jul 18 2002 - 14:49:50 MDT
>Beads of doubt
Didn't see this posted already, so I guess another first for me :)
>One of the most important principles of physics, that disorder, or
>entropy, always increases, has been shown to be untrue.
http://news.bbc.co.uk/hi/english/sci/tech/newsid_2135000/2135779.stm
>Scientists at the Australian National University (ANU) have carried out an
>experiment involving lasers and microscopic beads that disobeys the
>so-called Second Law of Thermodynamics, something many scientists had
>considered impossible.
>The finding has implications for nanotechnology - the design and
>construction of molecular machines. They may not work as expected.
>It may also help scientists better understand DNA and proteins, molecules
>that form the basis of life and whose behaviour in some circumstances is
>not fully explained.
>This Second Law of Thermodynamics says that the disorder of the Universe
>can only increase in time, but the equations of classical and quantum
>mechanics, the laws that govern the behaviour of the very small, are time
>reversible.
>A few years ago, a tentative theoretical solution to this paradox was
>proposed - the so-called Fluctuation Theorem - stating that the chances of
>the Second Law being violated increases as the system in question gets
>smaller.
>This means that at human scales, the Second Law dominates and machines
>only ever run in one direction. However, when working at molecular scales
>and over extremely short periods of time, things can take place in either
>direction.
>Now, scientists have demonstrated that principle experimentally.
>Emerging science
>The scientists say their finding could be important for the emerging
>science of nanotechnology. Researchers envisage a time when tiny machines
>no more than a few billionths of a metre across surge though our bodies to
>deliver drugs and destroy disease-causing pathogens.
>This research means that on the very small scales of space and time such
>machines may not work the way we expect them to.
>Essentially, the smaller a machine is, the greater the chance that it will
>run backwards. It could be extremely difficult to control.
>The researchers said: "This result has profound consequences for any
>chemical or physical process that occurs over short times and in small
>regions."
>The ANU work is published in Physical Review Letters.
James....
"If you can't take a little bloody nose, maybe you ought to go back home and
crawl under your bed. It's not safe out here. It's wondrous, with treasures
to satiate desires both subtle and gross. But it's not for the timid."
-Q, Star Trek:TNG episode 'Q Who'
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