Thus spake russell standish circa 07/08/2009 05:33 PM: > On Wed, Jul 08, 2009 at 10:16:55AM -0700, glen e. p. ropella wrote: >> Well, since my post consisted of questions, I could hardly be wrong. ;-) >> >> The question was: Is there any identifiable property of a system that is >> NOT an emergent property, regardless of how one defines "system"? If >> anyone knows of one, please name it! > > Absolutely! The positions of the particles in a Newtonian n-body system > are not emergent. Of course there are other properties of these > systems that are emergent, but position & momenta of the particles are > not amongst them, being part of the basic vocabulary of the model.
Excellent! Thanks Russell. However, I claim that the positions and momenta (note the plural) of the individual components are not properties of the _system_. Those are properties of the individual components. A systemic property related to those component properties might be a centroid or cumulative (averaged, summed, etc.) momentum for the system as a whole. Of course, the position or momentum of an individual particle is a systemic property of the system that constitutes that single particle (a system of quarks, say). The question then becomes, is a centroid or cumulative measure of a system of particles "emergent"? Or are the position and momentum of a system of quarks "emergent"? -- glen e. p. ropella, 971-222-9095, http://agent-based-modeling.com ============================================================ 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
