共查询到20条相似文献,搜索用时 15 毫秒
1.
In contrast to the Copenhagen interpretation we consider quantum mechanics as universally valid and query whether classical
physics is really intuitive and plausible. We discuss these problems within the quantum logic approach to quantum mechanics
where the classical ontology is relaxed by reducing metaphysical hypotheses. On the basis of this weak ontology a formal logic
of quantum physics can be established which is given by an orthomodular lattice. By means of the Solèr condition and Piron's
result one obtains the classical Hilbert spaces. However, this approach is not fully convincing. There is no plausible justification
of Solèr's law and the quantum ontology is partly too weak and partly too strong. We propose to replace this ontology by an
ontology of unsharp properties and conclude that quantum mechanics is more intuitive than classical mechanics and that classical
mechanics is not the macroscopic limit of quantum mechanics. 相似文献
2.
Giorgio Brida Maria Bondani Ivo P. Degiovanni Marco Genovese Matteo G. A. Paris Ivano Ruo Berchera Valentina Schettini 《Foundations of Physics》2011,41(3):305-316
With the purpose of introducing a useful tool for researches concerning foundations of quantum mechanics and applications
to quantum technologies, here we address three quantumness quantifiers for bipartite optical systems: one is based on sub-shot-noise
correlations, one is related to antibunching and one springs from entanglement determination. The specific cases of parametric
downconversion seeded by thermal, coherent and squeezed states are discussed in detail. 相似文献
3.
Laszlo Tisza 《Foundations of Physics》1999,29(3):491-495
The particles of quantum mechanics (QM) are discrete undulatory entities which are described in terms of the complex state vectors of the theory in full agreement with experiment. The wave-particle paradox stems from the fact that undulation and discreteness are inconsistent within the classical theory which was historically the point of departure for the canonical foundation. The author describes his prolonged efforts of anchoring the state vector of QM in experiment rather in obsolete theory. 相似文献
4.
Tomographic approach to describing both the states in classical statistical mechanics and the states in quantum mechanics
using the fair probability distributions is reviewed. The entropy associated with the probability distribution (tomographic
entropy) for classical and quantum systems is studied. The experimental possibility to check the inequalities like the position–momentum
uncertainty relations and entropic uncertainty relations are considered. 相似文献
5.
Alexander Davydov 《International Journal of Theoretical Physics》2011,50(5):1451-1467
In this paper, I present a mapping between representation of some quantum phenomena in one dimension and behavior of a classical time-dependent harmonic oscillator. For the first time, it is demonstrated that quantum tunneling can be described in terms of classical physics without invoking violations of the energy conservation law at any time instance. A formula is presented that generates a wide class of potential barrier shapes with the desirable reflection (transmission) coefficient and transmission phase shift along with the corresponding exact solutions of the time-independent Schrödinger’s equation. These results, with support from numerical simulations, strongly suggest that two uncoupled classical harmonic oscillators, which initially have a 90° relative phase shift and then are simultaneously disturbed by the same parametric perturbation of a finite duration, manifest behavior which can be mapped to that of a single quantum particle, with classical ‘range relations’ analogous to the uncertainty relations of quantum physics. 相似文献
6.
Fritz W. Bopp 《Foundations of Physics》2017,47(4):490-504
A two boundary quantum mechanics without time ordered causal structure is advocated as consistent theory. The apparent causal structure of usual “near future” macroscopic phenomena is attributed to a cosmological asymmetry and to rules governing the transition between microscopic to macroscopic observations. Our interest is a heuristic understanding of the resulting macroscopic physics. 相似文献
7.
We argue that it is fundamentally impossible to recover information about quantum superpositions when a quantum system has
interacted with a sufficiently large number of degrees of freedom of the environment. This is due to the fact that gravity
imposes fundamental limitations on how accurate measurements can be. This leads to the notion of undecidability: there is
no way to tell, due to fundamental limitations, if a quantum system evolved unitarily or suffered wavefunction collapse. This
in turn provides a solution to the problem of outcomes in quantum measurement by providing a sharp criterion for defining
when an event has taken place. We analyze in detail in examples two situations in which in principle one could recover information
about quantum coherence: (a) “revivals” of coherence in the interaction of a system with the measurement apparatus and the
environment and (b) the measurement of global observables of the system plus apparatus plus environment. We show in the examples
that the fundamental limitations due to gravity and quantum mechanics in measurement prevent both revivals from occurring
and the measurement of global observables. It can therefore be argued that the emerging picture provides a complete resolution
to the measurement problem in quantum mechanics. 相似文献
8.
G. P. Berman A. R. Bishop D. A. R. Dalvit G. V. Shlyapnikov N. Tarkhanov E. M. Timmermans 《International Journal of Theoretical Physics》2008,47(9):2393-2408
We rigorously analyze the stability of the “quasi-classical” dynamics of a Bose-Einstein condensate with repulsive and attractive
interactions, trapped in an effective 1D toroidal geometry. The “classical” dynamics, which corresponds to the Gross-Pitaevskii
mean field theory, is stable in the case of repulsive interaction, and unstable (under some conditions) in the case of attractive
interaction. The corresponding quantum dynamics for observables is described by using a closed system of linear partial differential
equations. In both cases of stable and unstable quasi-classical dynamics the quantum effects represent a singular perturbation
to the quasi-classical solutions, and are described by the terms in these equations which consist of a small quasi-classical
parameter which multiplies high-order “spatial” derivatives. We demonstrate that as a result of the quantum singularity for
observables a convergence of quantum solutions to the corresponding classical solutions exists only for limited times, and
estimate the characteristic time-scales of the convergence. 相似文献
9.
Marcel Polakovič 《International Journal of Theoretical Physics》2001,40(3):755-765
The convergence of the dynamics of classical projection to the dynamics of the classical limit is investigated for 0. A mistake from a previous paper is pointed out, and the correct version of the result is given. A new, similar result is presented if the function generating the Hamiltonian of both the classical projection and the classical limit is a polynomial. 相似文献
10.
Igor V. Volovich 《Foundations of Physics》2011,41(3):516-528
The Copenhagen interpretation of quantum mechanics assumes the existence of the classical deterministic Newtonian world. We
argue that in fact the Newton determinism in classical world does not hold and in the classical mechanics there is fundamental
and irreducible randomness. The classical Newtonian trajectory does not have a direct physical meaning since arbitrary real
numbers are not observable. There are classical uncertainty relations: Δq>0 and Δp>0, i.e. the uncertainty (errors of observation) in the determination of coordinate and momentum is always positive (non zero). 相似文献
11.
The properties of the eigenspace of nonintegrable quantum systems are explored in detail in the light of the viewpoint of quantum-classical completely correspondence proposed recently by Xu et al.The changes of the topological structure in the state space of autonomous quantum system due to the nonlinear resonance are displayed numerically with the uncertainty measure of a special initial state ρα(λ) and the transformation matrix U(λ δλ-λ-δλ),The statistical behavior of the subspace occupied by the state in eigenspace of quantum nonintegrable system is discussed carefully with the help of a special renormalization method.The results show that the randomness of effective Hamilonian matrix,the transition matrix and the nearest level spacings in this region can be described by random matrix theory.And the extent of agreement of our calculation with the prediction of GOE is in correspondence to the extent of the classical torus violation. 相似文献
12.
Don N. Page 《Foundations of Physics》2009,39(11):1197-1204
A motivation is given for expressing classical mechanics in terms of diagonal projection matrices and diagonal density matrices.
Then quantum mechanics is seen to be a simple generalization in which one replaces the diagonal real matrices with suitable
Hermitian matrices. 相似文献
13.
In spite of the interference manifested in the double-slit experiment, quantum theory predicts that a measure of interference
defined by Sorkin and involving various outcome probabilities from an experiment with three slits, is identically zero. We adapt Sorkin’s measure into a general operational probabilistic framework for physical theories,
and then study its relationship to the structure of quantum theory. In particular, we characterize the class of probabilistic
theories for which the interference measure is zero as ones in which it is possible to fully determine the state of a system
via specific sets of ‘two-slit’ experiments. 相似文献
14.
A parametric quantum mechanical wavefunction naturally induces parametric probability distributions by taking absolute square, and we can consider its classical Fisher information. On the other hand, it also induces parametric rank-one projections which may be viewed as density operators, and we can talk about its quantum Fisher information. Among many versions of quantum Fisher information, there are two prominent ones. The first, defined via a quantum score function, was introduced by Helstrom in 1967 and is well known. The second, defined via the square root of the density operator, has its origin in the skew information introduced by Wigner and Yanase in 1963 and remains relatively unnoticed. This study is devoted to investigating the relationships between the classical Fisher information and these two versions of quantum Fisher information for wavefunctions. It is shown that the two versions of quantum Fisher information differ by a factor 2 and that they dominate the classical Fisher information. The non-coincidence of these two versions of quantum Fisher information may be interpreted as a manifestation of quantum discord. We further calculate the difference between the Helstrom quantum Fisher information and the classical Fisher information, and show that it is precisely the instantaneous phase fluctuation of the wavefunctions. 相似文献
15.
JETP Letters - The detection of side radiation of transmitting devices is an additional source of information on distributed keys. In contrast to the attack on a quantum communication channel, the... 相似文献
16.
Dennis Dieks 《Foundations of Physics》2009,39(7):760-775
Pekka Lahti is a prominent exponent of the renaissance of foundational studies in quantum mechanics that has taken place during the last few decades. Among other things, he and coworkers have drawn renewed attention to, and have analyzed with fresh mathematical rigor, the threat of inconsistency at the basis of quantum theory: ordinary measurement interactions, described within the mathematical formalism by Schrödinger-type equations of motion, seem to be unable to lead to the occurrence of definite measurement outcomes, whereas the same formalism is interpreted in terms of probabilities of precisely such definite outcomes. Of course, it is essential here to be explicit about how definite measurement results (or definite properties in general) should be represented in the formalism. To this end Lahti et al. have introduced their objectification requirement that says that a system can be taken to possess a definite property if it is certain (in the sense of probability 1) that this property will be found upon measurement. As they have gone on to demonstrate, this requirement entails that in general definite outcomes cannot arise in unitary measuring processes.In this paper we investigate whether it is possible to escape from this deadlock. As we shall argue, there is a way out in which the objectification requirement is fully maintained. The key idea is to adapt the notion of objectivity itself, by introducing relational or perspectival properties. It seems that such a “relational perspective” offers prospects of overcoming some of the long-standing problems in the interpretation of quantum mechanics. 相似文献
17.
WANG Kaige CAO Dezhong 《量子光学学报》2004,10(Z1):4-5
Two-photon coincidence imaging (It is also called quantum or ghost imaging) can be carried out by an entangled two-photon quantum state.But a recent experiment (R.S.Bennink, et al, Phys.Rev.Lett.89, (2002) 113601) shows that this effect can be achieved using a classical source with a pair of correlated beams.In this work, we show that quantum and classical coincidence imaging can be incorporated into an optical system by using the spontaneous parametric down-conversion beam.The features of quantum and classical coincidence imaging are discussed. 相似文献
18.
19.
20.
Jose G. Vargas 《Foundations of Physics》2008,38(7):610-647
In 1960–1962, E. Kähler enriched É. Cartan’s exterior calculus, making it suitable for quantum mechanics (QM) and not only classical physics. His “Kähler-Dirac” (KD) equation reproduces the fine structure of the hydrogen atom. Its positron solutions correspond to the same sign of the energy as electrons. The Cartan-Kähler view of some basic concepts of differential geometry is presented, as it explains why the components of Kähler’s tensor-valued differential forms have three series of indices. We demonstrate the power of his calculus by developing for the electron’s and positron’s large components their standard Hamiltonian beyond the Pauli approximation, but without resort to Foldy-Wouthuysen transformations or ad hoc alternatives (positrons are not identified with small components in K ähler’s work). The emergence of negative energies for positrons in the Dirac theory is interpreted from the perspective of the KD equation. Hamiltonians in closed form (i.e. exact through a finite number of terms) are obtained for both large and small components when the potential is time-independent. A new but as yet modest new interpretation of QM starts to emerge from that calculus’ peculiarities, which are present even when the input differential form in the Kähler equation is scalar-valued. Examples are the presence of an extra spin term, the greater number of components of “wave functions” and the non-association of small components with antiparticles. Contact with geometry is made through a Kähler type equation pertaining to Clifford-valued differential forms. 相似文献