Free energy is the amount of energy in a system that is available to do work. A room with all its air molecules equally distributed will have energy but no free energy. If you put a heater in one corner of the room and a cooler in an opposite corner, this second system would have free energy and a device could be introduced to extract work from it.
How living systems identify sources of free energy and construct devices to use it is a central question in complex systems research (or should be more). Both Boltzmann and Shrodinger suggested living systems struggle not for energy but for free energy. Here's a recent working paper abstract from Eric and Harold Morowitz: Harold Morowitz and Eric Smith have a very approachable working paper on Origin of Life: http://www.santafe.edu/research/publications/wpabstract/200608029 ABSTRACT: Life is universally understood to require a source of free energy and mechanisms with which to harness it. Remarkably, the converse may also be true: the continuous generation of sources of free energy by abiotic processes may have forced life into existence as a means to alleviate the buildup of free energy stresses. This assertion -- for which there is precedent in non-equilibrium statistical mechanics and growing empirical evidence from chemistry -- would imply that life had to emerge on the earth, that at least the early steps would occur in the same way on any similar planet, and that we should be able to predict many of these steps from first principles of chemistry and physics together with an accurate understanding of geochemical conditions on the early earth. A deterministic emergence of life would reflect an essential continuity between physics, chemistry, and biology. It would show that a part of the order we recognize as living is thermodynamic order inherent in the geosphere, and that some aspects of Darwinian selection are expressions of the likely simpler statistical mechanics of physical and chemical self-organization. -S > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] > Sent: Wednesday, December 26, 2007 3:48 PM > To: [email protected] > Subject: [FRIAM] "free energy" > > At a Christmas eve party here in Santa Fe (the city very > different) , a number of new age or whatever folks were > talking about "free energy" which they claimed was a > scientific reality. Being somewhat of a sceptic and cynic, I > cried out a Dickens' humbug. But thought I would toss this > out to the FRIAM list to see if anyone knew anything about > so-called "free energy". cheers Paul > > > > ________________________________ > > See AOL's top rated recipes > <http://food.aol.com/top-rated-recipes?NCID=aoltop000300000000 > 04> and easy ways to stay in shape > <http://body.aol.com/fitness/winter-exercise?NCID=aoltop000300 > 00000003> for winter. > ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
