fishfry
15th April 2004 - 08:59 PM
http://news.bbc.co.uk/1/hi/sci/tech/2135779.stmI'm not enough of a physicist to determine whether this is revolutionary
or whether the reporter just got carried away.
Edward Green
15th April 2004 - 09:00 PM
Search for recent threads with keywords "thermodynamics" and "fluctuation".
Gregory L. Hansen
15th April 2004 - 09:01 PM
Science reporting at a major news service... hmm.. The reporter got
carried away. But let me read the article...
Ah, it's hundred year old physics. The second law -- thermodynamics in
general -- concerns macroscopic systems. At a more fundamental level, the
second law can be derived by considering the statistics of large numbers
of particles. And where there's statistics, there's standard deviations.
Thermal fluctuations have been studied for a long time. In another
thread, Meron has mentioned Brownian motion as an example of violations of
the second law; sometimes a dye particle goes faster and sometimes it goes
slower, which means sometimes it gained energy from a thermal bath without
transfering heat to a sink. Well, you won't build a car that runs
without fuel on that.
Sam Wormley
15th April 2004 - 09:01 PM
rsm109@york.ac.uk
15th April 2004 - 09:02 PM
The reporter seems to have got carried away. Thermodynamics is a
macroscopic theory that was never designed to be applied to small
systems, so it comes as no surprise that it doesn't.
Regarding "entropy = disorder",
<http://www.talkorigins.org/faqs/thermo/entropy.html> should be
required reading for anyone who plans to write about entropy and the
second law of thermodynamics. It's a loose analogy at best.
Uncle Al
15th April 2004 - 09:03 PM
1) The Second Law of Thermodyanimcs is statistical. "100 tiny
beads" has an inescapable error of 10 beads (sqrt(N)). This is a big
fraction for an allowed and expected spontaneous fluctuation. A mole
of stuff, 6x10^23 formula units, has an inescapable error of
7.7x10^11, which is a trivially negligible fraction.
2) Equilibrium thermodynamics is only valid for a closed systems.
The experiment in question is an open system (laser input plus
external vibratory driving).
3) Energy-rich systems far from equilibrium, with positive
feedback, spontaneously order. Consider the Belousov-Zhabotinsky
reaction. A planet accreted from a supernova shockwave - thereby
being sterile by heat and radiation - is scummed with all the
chemistry of life within a week of water condensing on its surface
(Miller, Ponnamperuma, Urey, Oparin... abiogenic synthesis). Wait a
couple of billion years and you have life arising spontaneously. Wait
five billion years and you get Edward Kennedy and Chappaquiddick.
Makes ya wonder why we even bother.
Augusta
17th September 2008 - 11:45 AM
sorry i dont have much information about it but i will try and than give some information about it... THanks..
Ovarian Cysts No More