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331	The complete Heyting algebra of subsystems and contextuality Vourdas, Apostolos January 2013 (has links) no / The finite set of subsystems of a finite quantum system with variables in Z(n), is studied as a Heyting algebra. The physical meaning of the logical connectives is discussed. It is shown that disjunction of subsystems is more general concept than superposition. Consequently, the quantum probabilities related to commuting projectors in the subsystems, are incompatible with associativity of the join in the Heyting algebra, unless if the variables belong to the same chain. This leads to contextuality, which in the present formalism has as contexts, the chains in the Heyting algebra. Logical Bell inequalities, which contain "Heyting factors," are discussed. The formalism is also applied to the infinite set of all finite quantum systems, which is appropriately enlarged in order to become a complete Heyting algebra. Finite hilbert-space Quantum-mechanics Hidden-variables Inequalities Nonlocality Systems Heyting algebra
332	Vibrational spectroscopic study of terbutaline hemisulphate Ali, H.R.H., Edwards, Howell G.M., Kendrick, John, Scowen, Ian J. 01 May 2009 (has links) No / The Raman spectrum of terbutaline hemisulphate is reported for the first time, and molecular assignments are proposed on the basis of ab initio BLYP DFT calculations with a 6-31G* basis set and vibrational frequencies predicted within the quasi-harmonic approximation; these predictions compare favourably with the observed vibrational spectra. Comparison with previously published infrared data explains several spectral features. The results from this study provide data that can be used for the preparative process monitoring of terbutaline hemisulphate, an important ß2 agonist drug in various dosage forms and its interaction with excipients and other components. Infrared spectroscopy Raman spectroscopy Quantum mechanics Terbutaline hemisulphate ß2 agonist Ab initio structural calculations
333	Vibrational spectroscopic study of salbutamol hemisulphate Ali, H.R.H., Edwards, Howell G.M., Kendrick, John, Scowen, Ian J. 01 January 2009 (has links) No / Salbutamol hemisulphate is a relatively selective ß2-adrenergic agonist and is used as a bronchodilator. In this work, we present a detailed vibrational spectroscopic investigation of salbutamol hemisulphate using mid-infrared and near-infrared Fourier-transform (NIR-FT) Raman spectroscopies. These data are supported by quantum chemical calculations, which allow us to characterise the vibrational spectra of this compound reasonably. As such, this study could be viable for examining the way in which this drug interacts with its target molecules. Infrared spectroscopy Raman spectroscopy Quantum mechanics Salbutamol hemisulphate ß2-adrenergic agonist Bronchodilator Vibrational spectra
334	Numerical Approach to the Landau-Zener Problem Käll, Niklas, Ulander, Emil January 2024 (has links) In quantum mechanics it is not uncommon to find analytically solved problems involvinga degree of math too advanced for most. It is often helpful to use a numerical approachto test solutions and deepen the understanding of such problems. In order to determine the validity of this approach, it is important to examine its accuracy. An exampleof this is the Landau-Zener problem, which is the topic of this thesis. It describes atwo-state quantum mechanical system that is applicable to many real world situations.The numerical method used involves propagating the wave function by calculating thetime evolution operator for numerous time steps. The accuracy using this method wasanalysed by comparing the results with the exact solution with varying parameters. Theconclusion is that the numerical solution does converge toward the known analytical solution. However, it does this with different accuracy, depending on the system parameters. Landau-Zener Quantum Mechanics Tunneling Numerical Methods Two-State System Physical Sciences Fysik
335	Topological Generalizations of the Heisenberg Uncertainty Relation Gandhi, Sohang 01 January 2006 (has links) It is well known that the standard canonical uncertainty relation does not apply to the angular variable ? and its conjugate LZ. That is, the relation ? ø ? L Z > h/2 is false. The break down of the result has to do with difference in topology between the line and the circle. It is thus desirable to generalize the standard uncertainty relation topologically and find satisfactory results for the non-Euclidean spaces. This problem is intimately related to the issue of finding a consistent definition for quantum mechanics on "curved spaces". Just as the Heisenberg uncertainty relation was pivotal in understanding the basic structure of standard quantum mechanics, a solution to this problem should shine some light onto the proper conduct of quantum mechanics on general topological spaces. In this study we explore in detail how the standard uncertainty relation may breakdown. We also address the importance of topological considerations in quantum mechanics in general - we shall show how a change in topological character can change the nature of the quantum mechanics for a system and how the consideration of the topology of a system can greatly organize the solution of a problem and in some cases even be necessary for a. full understanding of the problem. We then discuss the derivation of satisfactory uncertainty relations for the compact, homogeneous spaces of the circle, the n-torus and the n-sphere. Finally, we draw out any implications to the issue of properly defining quantum mechanics on the non- Euclidean spaces. Curved spaces; Quantum mechanics Physics
336	Dinâmica de dois condensados de Bose-Einstein - Tratamento de campo médio / Dynamics of two Bose-Einstein condensates: mean-field treatment Prandini, Renata Benedicto 01 October 2002 (has links) Investigamos o sistema formado por dois condensados aprisionados em estados hiperfinos diferentes do Rubídio, num potencial em forma de charuto, ou seja, num sistema físico real e quase-unidimensional. É investigada a dependência das soluções das equações de Gross-Pitaevski com a separação entre as armadilhas, bem como com o parâmetro de acoplamento de Josephson, para três valores diferentes do número total de átomos aprisionados. Para alguns conjuntos de parâmetros constatamos a existência de estados metaestáveis. O observável que escolhemos para caracterizar tal sistema físico foi a separação média entre os pacotes, pois os dois ramos de soluções encontramos correspondem a soluções mais juntas ou mais separadas espacialmente. / We study the system formed by two coupled condensates of different Rubidium hyperfine states trapped in a cigar shaped potential, that is, a real quasi one-dimensional system. The dependency of the solution of the Gross-Pitaevski equations is investigated as a function of trap displacement and Josephson coupling parameter for three different values of the total trapped atoms number. For some sets of parameters we report the existence of metastable states. The observable we chose to characterize this system was the mean separation between the packages, because we found two branches which correspond to closer or more separated solutions. Cigar-shaped potential Coexistence and phase separation Coexistence and phase separation Equation Gross-Pitaevski Gross-Pitaevski equation Potential cigar-shaped Quantum mechanics Quantum mechanics Two Bose-Einstein Two Bose-Einstein condensates
337	Superintégrabilité quantique avec une intégrale de mouvement de cinquième ordre Abouamal, Ismail 10 1900 (has links) No description available. Integrability Intégrabilité Superintégrabilité Propriété de Painlevé Mécanique quantique Integrability Superintegrablity Nonlinear differential equations Painlevé property Quantum mechanics Superintegrablity Nonlinear differential equations Painlevé property Quantum mechanics
338	Dinâmica de dois condensados de Bose-Einstein - Tratamento de campo médio / Dynamics of two Bose-Einstein condensates: mean-field treatment Renata Benedicto Prandini 01 October 2002 (has links) Investigamos o sistema formado por dois condensados aprisionados em estados hiperfinos diferentes do Rubídio, num potencial em forma de charuto, ou seja, num sistema físico real e quase-unidimensional. É investigada a dependência das soluções das equações de Gross-Pitaevski com a separação entre as armadilhas, bem como com o parâmetro de acoplamento de Josephson, para três valores diferentes do número total de átomos aprisionados. Para alguns conjuntos de parâmetros constatamos a existência de estados metaestáveis. O observável que escolhemos para caracterizar tal sistema físico foi a separação média entre os pacotes, pois os dois ramos de soluções encontramos correspondem a soluções mais juntas ou mais separadas espacialmente. / We study the system formed by two coupled condensates of different Rubidium hyperfine states trapped in a cigar shaped potential, that is, a real quasi one-dimensional system. The dependency of the solution of the Gross-Pitaevski equations is investigated as a function of trap displacement and Josephson coupling parameter for three different values of the total trapped atoms number. For some sets of parameters we report the existence of metastable states. The observable we chose to characterize this system was the mean separation between the packages, because we found two branches which correspond to closer or more separated solutions. Coexistence and phase separation Equation Gross-Pitaevski Potential cigar-shaped Quantum mechanics Two Bose-Einstein Cigar-shaped potential Coexistence and phase separation Gross-Pitaevski equation Quantum mechanics Two Bose-Einstein condensates
339	The Collapse of Decoherence : Can Decoherence Theory Solve The Problems of Measurement? Herlin, Karl January 2023 (has links) In this review study, we ask ourselves if decoherence theory can solve the problems of measurement in quantum mechanics. After an introduction to decoherence theory, we present the problem of preferred basis, the problem of non-observability of interference and the problem of definite outcomes. We present Zurek's theory of environment induced superselection rules and find that the problem of preferred basis and the problem of non-observability of interference can be solved through decoherence theory, but not the problem of outcomes, if we accept the eigenstate-eigenvalue link and the Born statistical interpretation. We reveal that these two concepts are essential in the Copenhagen interpretations of quantum mechanics, and give an account for von Neumann's and Wigner's conscious collapse interpretation as well as a detailed description of Bohr's and Heisenberg's interpretation. We discuss how Bohr's and Heisenberg's interpretation relates to decoherence with a special emphasis on the irreducibility of classical concepts as interpreted by Don Howard. During the discussion, we critique Wigner's use of the word "consciousness" as opposed to von Neumann's use, as well as Howard's decisively ontological approach to Bohr through an antithetical Kantian approach. We conclude by stating that decoherence theory cannot decisively solve the problem of definite outcomes of quantum mechanics, even when considering it in relation to the Copenhagen interpretation. quantum mechanics quantum physics philosophy of physics interpretation of quantum mechanics measurement problem problem of preferred basis problem of definite outcomes environment induced superselection rules copenhagen interpretation decoherence irreducibility of classical concepts Other Physics Topics Annan fysik
340	On the Quantization Problem in Curved Space Bernard, Benjamin 05 September 2012 (has links) No description available. Atoms and Subatomic Particles Condensed Matter Physics Mathematics Nanoscience Nanotechnology Nuclear Physics Physics Quantum Physics Solid State Physics Theoretical Mathematics Theoretical Physics quantum mechanics differential geometry constrained quantum mechanics schrodinger equation finite element method spheroid ellipsoid sphere cylinder

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