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1
Content available remote Algebraic approach to non-separable two-dimensional Schrödinger equation: Ground states for polynomial and Morse-like potentials
100%
Tichý V. , Skála L. , Hudec R.
Open Physics
|
2014
|
tom 12
|
nr 10
730-736
EN
This paper presents a direct algebraic method of searching for analytic solutions of the two-dimensional time-independent Schrödinger equation that is impossible to separate into two one-dimensional ones. As examples, two-dimensional polynomial and Morse-like potentials are discussed. Analytic formulas for the ground state wave functions and the corresponding energies are presented. These results cannot be obtained by another known method.
2
Content available remote On the origin of space
100%
Herrmann R.
Open Physics
|
2013
|
tom 11
|
nr 10
1212-1220
EN
Within the framework of fractional calculus with variable order the evolution of space in the adiabatic limit is investigated. Based on the Caputo definition of a fractional derivative using the fractional quantum harmonic oscillator a model is presented, which describes space generation as a dynamic process, where the dimension d of space evolves smoothly with time in the range 0 ≤ d(t) ≤ 3, where the lower and upper boundaries of dimension are derived from first principles. It is demonstrated, that a minimum threshold for the space dimension is necessary to establish an interaction with external probe particles. A possible application in cosmology is suggested.
3
Applications of quantum mechanics simulations in catalysis and fuel processing.
100%
Reynolds N.
|
|
tom Vol. 10, nr 57
115-118
EN
Advances in computational methods and computer hardware allow the application of molecular modeling and quantum mechanics simulations methods for the study of catalysis and fuel processing. Studies of atomistic models, including periodic boundary conditions, can be performed for the study of heterogeneous and homogeneous catalysis. Through these simulation methods, the energetics and mechanisms involved in chemical reactions can be elucidated. The effect of changes in surface structure on the reactivity can be directly seen, providing molecular level insight into reaction mechanisms. Examples of the use of two types of density functional theory methods for the study of catalytic reactions will be discussed.
4
Content available remote Quantum cards and quantum rods
100%
Batista M. , Peternelj J.
Open Physics
|
2008
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tom 6
|
nr 1
171-177
EN
Quantum mechanical analysis of a rigid rod with one end fixed to a flat table is presented. Assuming that the rod is initally in the upright orientation, “the time of fall” is calculated using WKB wavefunctions representing energy eigenstates near the barrier summit.
5
Content available remote Dynamical and structural symmetries for the highest Landau levels on the AdS 2
100%
Espoukeh P. , Fakhri H.
Open Physics
|
2012
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tom 10
|
nr 2
405-413
EN
The aim of the paper is to use the recurrence relations with respect to both indices of the associated Legendre functions for the extraction of the Dirac quantization condition and dynamical symmetry group U(1, 1) corresponding to the highest Landau levels on the hyperbolic plane with uniform magnetic field B. Irreducible representations of the su(2) algebra are obtained by the ladder differential operators which change B by 1/2 unit and mode number by one unit. Two different classes of the irreducible representations of SU(1, 1) with the even and odd boson numbers 2B − 1/2 are extracted for the Bargmann indices 1/4 and 3/4, respectively. Finally, we show that shape invariance symmetry is realized by the ladder operators which shift only the magnetic field B by 1/2 unit.
6
Content available remote Computational Tools Applied to Enzyme Design − a review
100%
García-Guevara F. , Avelar M. , Ayala M. , Segovia L.
Biocatalysis
|
2014
|
tom 1
|
nr 1
EN
The protein design toolbox has been greatly improved by the addition of enzyme computational simulations. Not only do they warrant a more ambitious and thorough exploration of sequence space, but a much higher number of variants and protein-ligand systems can be analyzed in silico compared to experimental engineering methods. Modern computational tools are being used to redesign and also for de novo generation of enzymes. These approaches are contingent on a deep understanding of the reaction mechanism and the enzyme’s three-dimensional structure coordinates, but the wealth of information produced by these analyses leads to greatly improved or even totally new types of catalysis.
7
Content available remote Quantum Cryptography - The Issue of Security in Selected Quantum Protocols and the Issue of Data Credibility
88%
Krzyszkowska-Pytel M.
|
2010
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tom Vol. 22, No. 1
73-92
EN
Quantum cryptography, a field of science that had not been known before, developed rapidly in the late 20th century. It originated from a combination of quantum mechanics and information technology. The present paper presents the possibilities of using quantum mechanics in cryptography and considers whether there are any practical solutions to the important class of problems regarding the security of transmitted information.
PL
Pod koniec XX - go wieku nastąpił gwałtowny rozwój nieznanej dotąd dziedziny - kryptografii kwantowej. Dziedzina ta wywodzi się ze splotu mechaniki kwantowej i informatyki. W niniejszym opracowaniu przedstawimy możliwości wykorzystania mechaniki kwantowej w kryptografii oraz zastanowimy się czy wynikają z nich praktyczne rozwiązywania dla istotnej klasy problemów związanych z bezpieczeństwem przesyłanej informacji.
8
Telekomunikacja kwantowa
88%
Zawadzki P.
|
2010
|
tom nr 10
1632-1638
PL
Kwantowe przetwarzanie informacji jest nową i dynamicznie rozwijającą się dziedziną badawczą na pograniczu fizyki kwantowej i informatyki. Urządzenia liczące oparte na prawach mechaniki kwantowej, jeżeli powstaną, umożliwią wykonywanie obliczeń równoległych na ogromną skalę. Niestety, efektem ubocznym tego ogromnego postępu będzie złamanie w zasadzie wszystkich funkcjonujących obecnie asymetrycznych systemów kryptograficznych, których bezpieczeństwo opiera się na obliczeniowej złożoności niektórych problemów. Jednak zanim ten długofalowy efekt zostanie osiągnięty, muszą zostać opracowane nowe kryptograficzne prymitywy wykorzystujące nowe paradygmaty bezpieczeństwa. Jednym z nich jest kryptografia kwantowa zapewniająca bezwarunkowe bezpieczeństwo protokołów uzgadniania klucza oparte na podstawowych prawach fizyki. W artykule wprowadzono podstawowe pojęcia związane z kwantowym przetwarzaniem informacji oraz omówiono wpływ nowych algorytmów kwantowych na istniejące metody uzgadniania klucza.
EN
Quantum Information processing is a new and dynamic research field at the boundaries of quantum physics and computer science. Computing devices based on quantum mechanical laws, if built, will provide massive parallel processing capabilities in the future. Unfortunately, the breaking of all asymmetric cryptosystems based on computational complexity would be the side effect of that tremendous progress. Thus, before this long term goal is achieved, a new cryptographic primitives, using quite different protections paradigms have to be developed. One of them is quantum cryptography, providing unconditionally secure key agreement protocols with protection mechanism exploiting the fundamental laws of physics. The paper introduces the basic notions related with quantum information processing and highlights the impact of novel quantum algorithms on existing key agreement methods. The quantum key distributions algorithms are explained and security limitations of their practical implementations exposed.
9
Content available Mechanika kwantowa a problem obiektywności
75%
Łukasik A.
Zagadnienia Naukoznawstwa
|
2015
|
tom 51
|
nr 2(204)
137-146
PL
W artykule argumentuję, że odróżnienie epistemologicznego i ontologicznego pojęcia obiektywności, oraz radykalnej obiektywności ontologicznej od obiektywności ontologicznej zrelatywizowanej do przyrządu pomiarowego pozwala na adekwatną analizę sytuacji poznawczej w mechanice kwantowej i przeciwstawienie się subiektywistycznym interpretacjom mechaniki kwantowej.
EN
In the article I argue that distinction between the epistemological notion and objectivity from ontological notion of objectivity, as well as radical ontological objectivity and ontological objectivity relative to the measuring instrument allows us for an adequate analysis of the cognitive situation in quantum mechanics and undermines the subjectivist interpretations of it.
10
Dwie tradycje naukowego poznawania świata. Studium przypadku powstania i recepcji mechaniki kwantowej w latach 1925–1927, na podstawie dyskusji Wernera Heisenberga i Alberta Einsteina
75%
Krajniak W.
Kwartalnik Historii Nauki i Techniki
|
2014
|
tom 59
|
nr 3
7–36
EN
The purpose of this article is the analyses of discussion between Albert Einstein and Werner Heisenberg in the period 1925-1927. Their disputes, relating to the sources of scientific knowledge, its methods and the value of knowledge acquired in this way, are part of the characteristic for the European science discourse between rationalism and empirism. On the basis of some sources and literature on the subject, the epistemological positions of both scholars in the period were reconstructed. This episode, yet poorly known, is a unique example of scientific disputes, whose range covers a broad spectrum of methodological problems associated with the historical development of science. The conducted analysis sheds some light on the source of popularity of logical empirism in the first half of the 20th century. A particular emphasis is placed on the impact of the neopositivist ideas which reflect Heisenberg's research program, being the starting point for the Copenhagen interpretation of quantum mechanics. The main assumption of logical empirism, concerning acquisition of scientific knowledge only by means of empirical procedures and logical analysis of the language of science, in view of the voiced by Einstein arguments, bears little relationship with actual testing practices in the historical aspect of the development of science. The criticism of Heisenberg's program, carried out by Einstein, provided arguments for the main critics of the neopositivist ideal and contributed to the bankruptcy of the idea of logical empirism, thereby starting a period of critical rationalism prosperity, arising from criticism of neopositivism and alluding to Einstein's ideas.
11
Content available remote Tunnelling time of a gaussian wave packet through two potential barriers
75%
Petrillo V. , Olkhovsky V.
Open Physics
|
2005
|
tom 3
|
nr 3
339-350
EN
The resonant and non-resonant dynamies of a Gaussian quantum wave packet travelling through a double barrier system is studied as a function of the initial characteristics of the spectrum and of the parameters of the potential. The behaviour of the tunnelling time shows that there are situations where the Hartman effect occurs, while, when the resonances are dominant, and in particular for b>π/Δk (b being the inter-barrier distance and Δk the spectrum width), the tunnelling time becomes very large and the Hartman effect does not take place.
12
Content available remote Wykorzystanie mechaniki kwantowej w geofizyce - stałe sprężyste forsterytu w wysokich ciśnieniach (wyniki wstępne)
63%
Jochym P. T. , Krzywiec P.
|
2000
|
tom Vol. 48, nr 8
683-688
PL
Uzyskano bardzo wysoką zgodność obliczonych równowagowych stałych sieci forsterytu z wartościami znanymi z pomiarów laboratoryjnych. Obliczenia zostały przeprowadzone przy zastosowaniu teorii funkcjonału gęstości (DFT) w ramach uogólnionego przybliżenia gradientowego (GGA). Uzyskano również generalnie dobrą zgodność zmian gęstości forsterytu wraz ze wzrostem ciśnienia z modelami globu.
EN
Preliminary results of calculation of selected elastic constants of olivine (forsterine - Mg_2SiO_4) under high pressure are presented. Pressures in the 0-80 GpA have been used. Density and bulk modulus as a function of pressure have been calculated as well. All calculations have been performed using Density Functional Theory (DFT) within Generalized Gradient Approximation Framework (GGA). Application of obtained results for interpretation of deep geophysical studies was disscussed.
13
Content available remote Zmierzch antropomorfizmu (na podstawie literatury fantastycznej)
51%
Tomalak B.
Świat i Słowo
|
2013
|
tom 11
|
nr 2(21)
95-106
EN
The article scrutinises exomimetic literature – both science fiction and fantasy – a genre which developed in the 20th century and appropriated traditional science fiction by creating hybrid forms, whose common denominator was the logic of presented world which exceeded the traditional physics. In the case of science fiction it is new physics, meta-physics, which is followed by nuclear physiology and cellular nuclear physics. It is also assumed that the behavior of the matter (also living matter) can be controlled by quantum physics on the level of nanometers. The feature shared by both, science fiction and fantasy, is the ability to trespass typically human limitations. They steer towards multiplied, intensified humanity. Towards non-human. In this respect both genres illustrate the decline of traditional humanity and of ordinary man.
14
Historia stałej Plancka
51%
Hemka L.
|
2010
|
tom nr 9 (73)
31-34
15
Content available Udawane filozofowanie
38%
Jodkowski K.
Filozoficzne Aspekty Genezy
|
2014
|
tom 11
279-302
PL
Recenzja książki: Wojciech Grygiel, Stephena Hawkinga i Rogera Penrose’a spór o rzeczywistość, Copernicus Center Press, Kraków 2014, s. 412.
EN
Review of: Wojciech Grygiel, Stephena Hawkinga i Rogera Penrose’a spór o rzeczywistość, Copernicus Center Press, Kraków 2014, s. 412.
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