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Dealing with quantum weirdness: Holism and related issues

Description: Various issues are discussed in interpretation of quantum mechanics. All these explorations point toward the same conclusion, that some systems are holistically connected, i.e., some composite systems have properties that cannot, even in principle, be reduced to the properties of its subsystems. This is argued to be the central metaphysical lesson of quantum theory; this will remain pertinent even if quantum mechanics gets replaced by a superior theory. Chap. 2 discusses nonlocality and rules out hidden-variable theories that approximately reproduce the perfect correlations of quantum mechanics, as well as theories that obey locality conditions weaker than those needed to derive Bell`s inequality. Chap. 3 shows that SQUID experiments can rule out non-invasive measurability if not macrorealism. Chap. 4 looks at interpretational issues surrounding decoherence, the dissipative interaction between a system and its environment. Decoherence klcan help ``modal`` interpretations pick out the desired ``preferred`` basis. Chap. 5 explores what varieties of causation can and cannot ``explain`` EPR correlations. Instead of relying on ``watered down`` causal explanations, we should instead develop new, holistic explanatory frameworks.
Date: December 1, 1995
Creator: Elby, A.R.
Partner: UNT Libraries Government Documents Department

Science of consciousness and the hard problem

Description: Quantum theory is essentially a rationally coherent theory of the interaction of mind and matter, and it allows our conscious thoughts to play a causally efficacious and necessary role in brain dynamics. It therefore provides a natural basis, created by scientists, for the science of consciousness. As an illustration it is explained how the interaction of brain and consciousness can speed up brain processing, and thereby enhance the survival prospects of conscious organisms, as compared to similar organisms that lack consciousness. As a second illustration it is explained how, within the quantum framework, the consciously experienced {open_quotes}I{close_quotes} directs the actions of a human being. It is concluded that contemporary science already has an adequate framework for incorporating causally efficacious experimential events into the physical universe in a manner that: (1) puts the neural correlates of consciousness into the theory in a well defined way, (2) explains in principle how the effects of consciousness, per se, can enhance the survival prospects of organisms that possess it, (3) allows this survival effect to feed into phylogenetic development, and (4) explains how the consciously experienced {open_quotes}I{close_quotes} can direct human behaviour.
Date: May 22, 1996
Creator: Stapp, H.P.
Partner: UNT Libraries Government Documents Department

Measurement accuracy, bit-strings, Manthey`s quaternions, and RRQM

Description: The author continues the discussion started last year. By now three potentially divergent research programs have surfaced in ANPA: (1) the Bastin-Kilmister understanding of the combinatorial hierarchy (Clive`s {open_quotes}Menshevik{close_quotes} position); (2) the author`s bit-string {open_quotes}Theory of Everything{close_quotes} (which Clive has dubbed {open_quotes}Bolshevik{close_quotes}); (3) Manthey`s cycle hierarchy based on co-occurrence and mutual exclusion that Clive helped him map onto quaternions (as an yet unnamed heresy?). Unless a common objective can be found, these three points of view will continue to diverge. The authors suggests the reconstruction of relativistic quantum mechanism (RRQM) as a reasonable, and attainable, goal that might aid convergence rather than divergence.
Date: February 1, 1995
Creator: Noyes, H. P.
Partner: UNT Libraries Government Documents Department

Quantum theory and the emergence of patterns in the universe

Description: The topic of this symposium is the quest to discover, define, and interpret patterns in the universe. This quest has two parts. To discover and define these patterns is the task of science: this part of the quest is producing a copious flow of reliable information. To interpret or give meaning to these patterns is the task of natural philosophy: this part has not kept pace.
Date: November 1, 1989
Creator: Stapp, H. P.
Partner: UNT Libraries Government Documents Department

The integration of mind into physics

Description: The proper goal of science is a unified theory of all of nature, including our thoughts. An adequate theory of this kind will resolve the quantum measurement problem, which is to reconcile the nonclassical character of the quantum world with the classical character of our perceptions of it. A framework for such a theory is described. It weds the opposing views of Bohr and Einstein. Bohr held that quantum theory provides rules that relate aspects of our knowledge, while Einstein claimed that basic theory should describe what could be reality itself, not merely our knowledge of it.
Date: July 13, 1994
Creator: Stapp, H. P.
Partner: UNT Libraries Government Documents Department

On the computer simulation of the EPR-Bohm experiment

Description: We argue that supraluminal correlation without supraluminal signaling is a necessary consequence of any finite and discrete model for physics. Every day, the commercial and military practice of using encrypted communication based on correlated, pseudo-random signals illustrates this possibility. All that is needed are two levels of computational complexity which preclude using a smaller system to detect departures from ''randomness'' in the larger system. Hence the experimental realizations of the EPR-Bohm experiment leave open the question of whether the world of experience is ''random'' or pseudo-random. The latter possibility could be demonstrated experimentally if a complexity parameter related to the arm length and switching time in an Aspect-type realization of the EPR-Bohm experiment is sufficiently small compared to the number of reliable total counts which can be obtained in practice. 6 refs.
Date: December 1, 1988
Creator: McGoveran, D.O.; Noyes, H.P. & Manthey, M.J.
Partner: UNT Libraries Government Documents Department

Realization of vector fields for quantum groups as pseudodifferential operators on quantum spaces

Description: The vector fields of the quantum Lie algebra are described for the quantum groups GL{sub q}(n), SL{sub q}(N) and SO{sub q}(N) as pseudodifferential operators on the linear quantum spaces covariant under the corresponding quantum group. Their expressions are simple and compact. It is pointed out that these vector fields satisfy certain characteristic polynomial identities. The real forms SU{sub q}(N) and SO{sub q}(N,R) are discussed in detail.
Date: January 24, 1995
Creator: Chu, Chong-Sun & Zumino, B.
Partner: UNT Libraries Government Documents Department

Exact, E = 0, classical and quantum solutions for general power-law oscillators

Description: For zero energy, E = 0, we derive exact, classical and quantum solutions for all power-law oscillators with potentials V(r) = {minus}{gamma}/r{sup {nu}}, {gamma} > 0 and {minus}{infinity} < {nu} < {infinity}. When the angular momentum is non-zero, these solutions lead to the classical orbits {rho}(t) = [cos {mu}({var_phi}(t) {minus} {var_phi}{sub 0}(t))]{sup 1/{mu}}, with {mu} = {nu}/2 {minus} 1 {ne} 0. For {nu} > 2, the orbits are bound and go through the origin. We calculate the periods and precessions of these bound orbits, and graph a number of specific examples. The unbound orbits are also discussed in detail. Quantum mechanically, this system is also exactly solvable. We find that when {nu} > 2 the solutions are normalizable (bound), as in the classical case. Also, there are normalizable discrete, yet unbound, state which correspond to unbound classical particles which reach infinity in a finite time. These and other interesting comparisons to the classical system will be discussed.
Date: July 1, 1994
Creator: Nieto, M. M. & Daboul, J.
Partner: UNT Libraries Government Documents Department

Magnetic field induced minigap in double quantum wells

Description: We report discovery of a partial energy gap, or minigap, in strongly coupled double quantum wells (QWs), due to an anticrossing of the two QW dispersion curves. The anticrossing and minigap are induced by an in-plane magnetic field B{sub {parallel}}, and give rise to large distortions in the Fermi surface and density of states, including a Van Hove singularity. Sweeping B{sub {parallel}} moves the minigap through the Fermi level, with the upper and lower gap edges producing a sharp maximum and minimum in the low-temperature in-plane conductance, in agreement with theoretical calculations. The gap energy may be directly determined from the data.
Date: July 1, 1994
Creator: Simmons, J. A.; Lyo, S. K.; Klem, J. F. & Harff, N. E.
Partner: UNT Libraries Government Documents Department

Decoherence, determinism and chaos revisited

Description: We suggest that the derivation of the free space Maxwell Equations for classical electromagnetism, using a discrete ordered calculus developed by L.H. Kauffman and T. Etter, necessarily pushes the discussion of determinism in natural science down to the level of relativistic quantum mechanics and hence renders the mathematical phenomena studied in deterministic chaos research irrelevant to the question of whether the world investigated by physics is deterministic. We believe that this argument reinforces Suppes` contention that the issue of determinism versus indeterminism should be viewed as a Kantian antinomy incapable of investigation using currently available scientific tools.
Date: November 15, 1994
Creator: Noyes, H. P.
Partner: UNT Libraries Government Documents Department

Complex scattering dynamics and the quantum Hall effects

Description: We review both classical and quantum potential scattering in two dimensions in a magnetic field, with applications to the quantum Hall effect. Classical scattering is complex, due to the approach of scattering states to an infinite number of dynamically bound states. Quantum scattering follows the classical behavior rather closely, exhibiting sharp resonances in place of the classical bound states. Extended scatterers provide a quantitative explanation for the breakdown of the QHE at a comparatively small Hall voltage as seen by Kawaji et al., and possibly for noise effects.
Date: December 16, 1994
Creator: Trugman, S. A.
Partner: UNT Libraries Government Documents Department

Scattering theory for the quantum envelope of a classical system

Description: Classical dynamics, reformulated in terms of its quantum envelope is studied for the stationary states of the interacting system. The dynamical variable of ``elapsed time`` plays a crucial role in this study. It is shown that the perturbation series for the elapsed time can be summed in various simple cases even when standard perturbation series diverge. For the special class of systems where the interactions fall off sufficiently fast at infinity one could define ``in`` and ``out`` states; and consequently the wave matrices and scattering matrices. The scattering phase shifts bear a simple relation to the time delay in scattering.
Date: December 31, 1993
Creator: Sudarshan, E. C. G.
Partner: UNT Libraries Government Documents Department

Localizability and the planck mass

Description: The author combines the assumption of environmental decoherence, as the mechanism generating the classical (i.e. no quantum interferences) nature of spacetime, with the limit on its other classical feature, point-like continuity, namely Planck length. As a result, quantum extended objects with masses larger than Planck mass have to derive their quantum behavior from long-range correlations; objects with masses smaller than Planck mass cannot display classical behavior.
Date: June 1, 1993
Creator: Ne`eman, Y.
Partner: UNT Libraries Government Documents Department

Symplectic structure of isospin particles in Yang-Mills fields

Description: Using Dirac`s constraint analysis, we explore the Hamiltonian formalism of isospin particles in external Yang-Mills fields without kinetic and potential energy term. We consider an example of isospin particle in `t Hooft-Polyakov magnetic monopole field and discuss possible quantization condition of magnetic charge in terms of geometric quantization.
Date: January 1, 1992
Creator: Oh, P.
Partner: UNT Libraries Government Documents Department

A quantum-drive-time (QDT) quantization of the Taub cosmology

Description: We present here an application of a new quantization scheme. We quantize the Taub cosmology by quantizing only the anisotropy parameter {beta} and imposing the super-Hamiltonian constraint as an expectation-value equation to recover the relationship between the scale factor {Omega} and time t. This approach appears to avoid the problem of time.
Date: October 1, 1994
Creator: Miller, W. A. & Kheyfets, A.
Partner: UNT Libraries Government Documents Department

Restoring locality with faster-than-light velocities

Description: The idea of ``locality`` is a deep rooted concept. It does not have to be abandoned even if ``loophole free`` EPR experiments are performed and confirm the predictions of quantum theory. To satisfy locality, one can imagine that influences at a distance are exerted via mechanisms involving an ether and effects propagating in that ether a velocity V > c. Such model of physical phenomena is not Lorentz invariant but, with V large enough, the model can be made to reproduce the results of all experiments where quantum mechanics and Lorentz invariance have been verified.
Date: August 30, 1993
Creator: Eberhard, P. H.
Partner: UNT Libraries Government Documents Department

PHOTOTHERMAL DEFLECTION SPECTROSCOPY AND DETECTION

Description: The theory for a sensitive spectroscopy based on the photothermal deflection of a laser beam is developed. We consider cw and pulsed cases of both transverse and collinear photothermal deflection spectroscopy for solids, liquids, gases, and thin films. The predictions of the theory are experimentally verified, its implications for imaging and microscopy are given, and the sources of noise are analyzed. The sensitivity and versatility of photothermal deflection spectroscopy are compared with thermal lensing and photoacoustic spectroscopy.
Date: September 1, 1980
Creator: Jackson, W.; Amer, Nabil M.; Boccara, A. C. & Fournier, D.
Partner: UNT Libraries Government Documents Department

THERMAL RADIATION OF SPHERICAL AND CYLINDRICAL SOOT PARTICLES

Description: The effect of soot shape on soot radiation from flame and smoke is considered in the present study. It is realized that soot particles generally conglomerate into different shapes. while the limiting bounds are being either spherical or long chains. By modellirig the long chains as infinite cylinders, it is shown that the radiation extinction characteristics of the spherical and cylindrical soot are distinctly different, with that of the spherical particles exhibiting a cut-off wavelength phenomenon. Emissivity from a cloud of cylindrical particles is always higher than that of the spheres due to their higher extinction coefficients. Moreover, the effect of soot shape onradiation is more pronounced at typical smoke temperatures (300°K) than at flame temperatures. A simple experimental method is also proposed for determining the amount of cylindrical and spherical particles in a cloud.
Date: October 1, 1980
Creator: Lee, S. C. & Tien, C. L.
Partner: UNT Libraries Government Documents Department

STRONG COUPLING EXPANSIONS FOR NON-INTEGRABLE HAMILTONIAN SYSTEMS

Description: We present a method for studying nonintegrable Hamiltonian systems H(I,{theta})=H{sub 0}(I)+kH{sub 1}(I,{theta}) (I,{theta} are action-angle variables) in the reg1me of large k. Our central tool is the conditional probability P(I,{theta},t|I{sub 0},{theta}{sub 0},t{sub 0}) that the system is at I,{theta} at time t given that it resided at I{sub 0},{theta}{sub 0} at t{sub 0}. An integral representation is given for this conditional probability. By discretizing the Hamiltonian equations of motion in small time steps, {epsilon}, we arrive at a phase volume preserving mapping which replaces the actual flow. When the motion on the energy surface E=H(I,{theta}) is bounded we are able to evaluate physical quantities of interest for large k and fixed {epsilon}. We also discuss the representation of P(I,{theta},t|I{sub 0},{theta}{sub 0},t{sub 0}) when an external random forcing is added in order to smooth the singular functions associated with the deterministic flow. Explicit calculations of a "diffusion" coefficient are given for a non-integrable system with two degrees of freedom. The limit {epsilon}{approaches}0 , which returns us to the actual flow, is subtle and is discussed.
Date: December 1, 1980
Creator: Abarbanel, Henry D.I. & Crawford, John David
Partner: UNT Libraries Government Documents Department

DIFFUSION IN VERY CHAOTIC HAMILTONIAN SYSTEMS

Description: We study nonintegrable Hamiltonian dynamics: H(I,{theta}}) = H{sub 0}(I)+kH{sub 1}(I,{theta}) for large k; that is, far from integrability. An integral representation is given for the conditional probability P(I,{theta},t|I{sub 0},{theta}{sub 0},t{sub 0}) that the system is at I,{theta} at t, given it was at I{sub 0},{theta}{sub 0} at t{sub 0}. By discretizing time into steps of size {epsilon}, we show how to evatuate physical observables for large k, fixed {epsilon}. An explicit calculation of a diffusion coefficient in a two degree of freedom problem is reported. Passage to {epsilon} = 0, the original Hamiltonian flow, discussed.
Date: December 1, 1980
Creator: Abarbanel, Henry D.I. & Crawford, John David
Partner: UNT Libraries Government Documents Department