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From: Ken S. Tucker on 4 May 2010 00:58 On May 3, 6:36 pm, Bob_for_short <vladimir.kalitvian...(a)wanadoo.fr> wrote: > On 3 mai, 05:54, "Rich L." <ralivings...(a)sbcglobal.net> wrote: > > Another related question has to do with setting up this superposition > > state. Suppose we do it via collision with an excited atom that is > > excited to E=(E1+E2)/2, and after the collision the prepared atom then > > has this energy as a superposition state. Would that work? > > No, if the transferred energy is not sufficient to excite E2, the > latter will not be present in the superposition (effect of threshold). > If the transferred energy is larger than E2, both E1 and E2 will be > present (and maybe some other levels allowed with the energy > conservation law). > > > > Is the uncertainty one of knowledge or reality? > > > > This is a drawback of our tendency to simplify complex things. There > > > are things that cannot be taken apart (disassembled, demounted, taken > > > down to pieces, separated in time and space). > > > And yet our concept of conservation of energy is considered to apply > > at all instances in time, and for all observers (with their own > > concept of an instant in time). How can the universe deal with an > > uncertaintly in energy over a macroscopic time (e.g. greater than the > > Uncertaintly Principle)? > > Consider collision of two atoms. when at large distance from each > other, they have certaing kinetic and internal energies. While > collision the total energy is numerically the same but it is > impossible to attribute some parts of it to some parts of colliding > system (tha atoms "merge"). After collision the total energy is > somehow distributed between the collision products that may be > asymptotically well defined with their kinetic and internal energies. > So the energy conservation law is applicable at each instant of time > but its additiveness is not always. The timing is important and it may > be determined not only with atomic sizes but also with the wave packet > sizes. The latter are mostly determined with the preparation device. Minor point for interest. Bob wrote, "preparation device". Rocket engines, heated gases colliding with a surface, that appears to use the outer electron shells in repulsion is a realistic device, http://en.wikipedia.org/wiki/F-1_(rocket_engine) An obvious macroscopic application. I'd interprete Bob's "additiveness is not always" as being a kin to when the actual walls of the Combustion Chamber begin to vaporize as the exterior electron shells in the CC are over heated, which - by common sense - would suck energy by the vaporization process. Regards Ken S. Tucker |