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Article #4511QUANTUM KITTENS
From: Jack Sarfatti
Date: Sun, 04 Oct 1992 04:47
Date: Sun, 04 Oct 1992 04:47
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5855 bytes
On Quantum Kitty Cats, Zeh writes: "As soon as the states of the environment have approximately become mutually orthogonal by a sufficiently large number of collisions ... The relative phases characterizing the superposition of different [macroscopic] values ... are therefore irreversibly 'delocalized' (it decoheres locally) if the incoming photons (or other particles) satisfy an appropriate Sommerfeld-type condition of lacking conspirative correlations (Boltzmann's chaos for quantum phases). Even if the collapse is not explicitly taken into account up to this time, superpositions of the different macroscopic states sre no longer present at the local system under consideration. Once this decoherence has practically become irreversible, local observers may pretend that the macroscopic quantities, such as the outcomes of measurements, really exist and are mearely unknown. This is a dynamical justification of superselection rules for macroscopic quantities, and of the otherwise quantum mechanically unjustified concept of a physical entropy ... p.94 THE DIRECTION OF TIME ... classical concepts ... emerge ... as a dynamical consequence of their unavoidable continuous 'measurement' by the environment, a process that leads to the delocalization of phase relations which would define their superpositions. Classical concepts and their histories (trajectories in their configuration space [the starting point of classical chaos with fractal strange attractors - Sarfatti interjection] become 'excess baggage' from a fundamental point of view (John Hartle, 1989 UCSB preprint). If the robust quantum variable x.. is a continuous quantity, such as the center of mass position of a dust particle, or the orientation in space of a macroscopic molecule, its interference will be suppressed according to a time-dependent gaussian ... exp[-at(x-x')^2] 4.36 where a is determined by the rate and efficiency of the scattering. (p.95).. [irreversible] decoherence competes with the [reversible] dispersion of the wave packet....even the rate of scattering of photons or hydrogen atoms which are present in 'empty' intergalactic space would be sufficient to overcompensate the coherent spreading of initially narrow center-of-mass wave packets for small dust particles or mediun-sized molecules. This decoherence acts on a much faster time scale than thermal relaxation (Zurek, 1986). [The decoherence Gaussian] corresponds to the infinite-mass limit of quantum Brownian motion [what about quantum pink and black motion? Sarfatti].. this effect is not due to a stochastic ... 'kicking' or 'chopping' (p.96) .. Remarkably, it is precisely the form as the non- unitary dynamics that has been postulated .. in order to describe von Neumann's collapse of the wave function. ...no interference fringes could ever be observed in the case of diffraction experiments with macroscopic objects or large molecules - even if the experimentally achievable resolution permitted it. [this feature is also found in my superluminal connection communication gedanken exeriment where there is never any first order coherence (local fringes) at the transmitter interferograms because of the nonlocal correlations of the transmitter photon(s) to orthogonal states of the twin receiver photon (s) - even though uncorrelated light with same local power spectrum would show fringes. The receiver photon is the analog of the "environmental" degrees of freedom. The transmitter phase information from the variable phase plate does not manifest locally at the transmitter but does manifest locally at the receiver as a shift in the relative counting rates of the two receiver counters (there is only one transimitter counter coherently inputing each of the two interferogram outputs from the unitary transmitter beam recombiner to get the effect at the far away receiver- Sarfatti comment] .. the information about the delocalized (though still existing) relative phases vanishes ... the additive (local) entropy monotonically increases as a result of this continuous measurement (without reading the result). In particular, the 'classical' realization of a bit of information in a quantum computer cause by such interaction with the environment would have to produce an amount of entropy of the order of just the conjectured minimum kln2 ... the genetic code lll utilizes molecular degrees of freedom which are classical in this sense . As a consequence of Zeon's quantum paradox (or the watchdog effect), this seems to also increase their stability (p.96) .. this effect is not caused by the collapse of the wavefunction .. but requires merely the entanglement with the environment... only for discrete states of sufficiently low density- otherwise the entanglement merely justifies the neglect of phases in the derivation of master equations. [Reversibility without reversibility? _Sarfatti variation on a theme by Wheeler] It is further remarkable that the classical phenomena described by Newtonian mechanics - which in the absence of frictional forces.are usually considered as reversible - paradoxically arise in this quantum mechanical description from the continuous irreversible decoherence (somewhat remiiscent of the dissipative structures appearing in non-equilibrium processes). While the entropy produced thereby is completely negligible on a macroscopic scale, it is very large in units of kln2. ... a quantum demon would have to decohere the world (p.97)...
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Newsgroups: sci.physics Path: arc1-ca.pugleaf.net!sparky!uunet!charon.amdahl.com!pacbell.com!well!sarfatti From: sarfatti@well.sf.ca.us (Jack Sarfatti) Subject: QUANTUM KITTENS Message-ID: <BvKyn9.EEo@well.sf.ca.us> Sender: news@well.sf.ca.us Organization: Whole Earth 'Lectronic Link Date: Sun, 4 Oct 1992 04:47:33 GMT Lines: 80