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1.
Abstract

The Moser type reductions of modified Boussinessq and super-Korteweg-de Vries equations upon the finite-dimensional invariant subspaces of solutions are considered. For the Hamiltonian and Liouville integrable finite-dimensional dynamical systems concerned with the invariant subspaces, the Lax representations via the dual moment maps into some deformed loop algebras and the finite hierarchies of conservation laws are obtained. A supergeneralization of the Neumann dynamical system is presented.  相似文献   

2.
Departing from the symbolic dynamics, we study natural group action on spaces of holomorphic maps and complex subvarieties.  相似文献   

3.
Abstract

The Einstein field equations for several cosmological models reduce to polynomial systems of ordinary differential equations. In this paper we shall concentrate our attention to the spatially homogeneous diagonal G 2 cosmologies. By using Darboux’s theory in order to study ordinary differential equations in the complex projective plane ??2 we solve the Bianchi V models totally. Moreover, we carry out a study of Bianchi VI models and first integrals are given in particular cases.  相似文献   

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A procedure to construct positive knots motivated by symbolic dynamics is given. It is proved that the corresponding knots have a special type of positive braids, positive permutation braids. It is proved that the constructed knots are invariant under topological conjugacy, up to period five, hence they can be used to classify discrete dynamical systems. An example is given to show that topological conjugacy failed to be an invariant for closed orbits of period more than five.  相似文献   

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7.
Aspects of quantum entropy and relative quantum entropy are discussed in the Hilbert model. It is shown that finite values of the relative entropy of states implies a superposition relation between the states. The property is studied in case of tensor product of states and for state reductions. A “Schmidt-like” state, derived from the reduced states, is considered. It is shown that its entropy, relative to the product of the reduced states, is not smaller than the entropy of the reduced states. The main existing results concerning the changement of superposition and entropy under dynamical map are recalled in a uniform way. A class of possible dynamical maps, not necessarily linear, is proposed that do not decrease the entropy.  相似文献   

8.
The problem of the validity and interpretation of the energy-time uncertainty relation is briefly reviewed and reformulated in a systematic way. The Bohr-Einsteinphoton-box gedanken experiment is seen to illustrate the complementarity of energy andevent time. A more recent experiment with amplitude-modulated Mößbauer quanta yields evidence for the genuine quantum indeterminacy of event time. In this way, event time arises as a quantum observable.Dedicated to my parents on the occasion of their 60th birthdays.  相似文献   

9.
We present an N=2-supersymmetric mechanical system whose bosonic sector, with two degrees of freedom, exhibits the most general possible supersymmetric fourth order potential, including the interesting case of SU(2) Yang–Mills theory. The Painlevé test is adopted to discuss integrability and we focus on the rôle of supersymmetry and parity invariance in two space dimensions for the attainment of integrable or non-integrable models, with some remarks on the chaotic behavior. Our result shows that, for the model studied here, the relationships among the parameters, as imposed by supersymmetry, restrict the parameter space in such a way that the reduction on its non-integrable sector is much more severe than on its integrable sector (especially on the non-separable subset of the latter), thus suggesting that supersymmetry may favor (mainly non-separable) integrability.  相似文献   

10.
Union pseudogroups (structures analogical to pseudogroups in the sense of [1]) are defined using the category dual to the category of groupoids instead of the category of pseudospaces in the sense of [2]. It is shown that these structures are equivalent to double groups (in the sense of [3]). Moreover, it is shown that a quantization procedure associates with each finite union pseudogroup a (quantum) pseudogroup. Therefore for each finite double group there is a finite pseudogroup.  相似文献   

11.
It is shown that the two-component Camassa-Holm and Hunter-Saxton systems are geometrically integrable, namely they describe pseudo-spherical surfaces. As a consequence, their infinite number of conservation laws are directly constructed. In addition, a class of nonlocal symmetries depending on the pseudo-potentials are obtained.  相似文献   

12.
We consider a system consisting of a planar random walk on a square lattice, subjected to stochastic elementary local deformations. Both numerical and theoretical results are reported. Depending on the deformation transition rates, and specifically on a parameter η which breaks the symmetry between the left and right orientation, the winding distribution of the walk is modified, and the system can be in three different phases: folded, stretched and glassy. An explicit mapping is found, leading to consider the system as a coupling of two exclusion processes: particles of the first one move in a landscape defined by particles of the second one, and vice-versa. This can be viewed as an inhomogeneous exclusion process. For all closed or periodic initial sample paths, a convenient scaling permits to show a convergence in law (or almost surely on a modified probability space) to a continuous curve, the equation of which is given by a system of two non linear stochastic differential equations. The deterministic part of this system is explicitly analyzed via elliptic functions. In a similar way, by using a formal fluid limit approach, the dynamics of the system is shown to be equivalent to a system of two coupled Burgers equations.  相似文献   

13.
We define a natural class of star products: those which are given by a series of bidifferential operators which at order k in the deformation parameter have at most k derivatives in each argument. This class includes all the standard constructions of star products. We show that any such star product on a symplectic manifold defines a unique symplectic connection. We parametrise such star products, study their invariance properties and give necessary and sufficient conditions for them to have a quantum moment map. We show that Kravchenko's sufficient condition for a moment map for a Fedosov star product is also necessary.  相似文献   

14.
Letters in Mathematical Physics - Scattering amplitudes in planar $${\mathcal{N}=4}$$ super Yang–Mills theory reveal a remarkable symmetry structure. In addition to the superconformal...  相似文献   

15.
In this paper we continue the development of a relative version of T-duality in generalized complex geometry which we propose as a manifestation of mirror symmetry. We discuss the integrability of the transform from Part I in terms of data on the base manifold. We work with semi-flat generalized complex structures on real n-torus bundles with section over an n-dimensional base and use the transform on vector bundles developed in Part I of this paper to discuss the bijective correspondence between semi-flat generalized complex structures on pairs of dual torus bundles. We give interpretations of these results in terms of relationships between the cohomology of torus bundles and their duals. We comment on the ways in which our results generalize some well established aspects of mirror symmetry. Along the way, we give methods of constructing generalized complex structures on the total spaces of the bundles we consider.  相似文献   

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17.
 Given a countably infinite 0–1 matrix A without identically zero rows, let 𝒪 A be the Cuntz–Krieger algebra recently introduced by the authors and 𝒯 A be the Toeplitz extension of 𝒪 A , once the latter is seen as a Cuntz–Pimsner algebra, as recently shown by Szymański. We study the KMS equilibrium states of C * -dynamical systems based on 𝒪 A and 𝒯 A , with dynamics satisfying for the canonical generating partial isometries s x and arbitrary real numbers N x > 1. The KMSβ states on both 𝒪 A and 𝒯 A are completely characterized for certain values of the inverse temperature β, according to the position of β relative to three critical values, defined to be the abscissa of convergence of certain Dirichlet series associated to A and the N(x). Our results for 𝒪 A are derived from those for 𝒯 A by virtue of the former being a covariant quotient of the latter. When the matrix A is finite, these results give theorems of Olesen and Pedersen for 𝒪 n and of Enomoto, Fujii and Watatani for 𝒪 A as particular cases. Received: 21 November 2000 / Accepted: 31 May 2002 Published online: 22 November 2002 RID="*" ID="*" Partially supported by CNPq RID="**, ***"  相似文献   

18.
We obtain a new inequality for arbitrary Hermitian matrices. We describe particular linear maps called the matrix portrait of arbitrary N × N matrices. The maps are obtained as analogs of partial tracing of density matrices of multipartite qudit systems. The structure of the maps is inspired by “portrait” map of the probability vectors corresponding to the action on the vectors by stochastic matrices containing either unity or zero matrix elements. We obtain new entropic inequalities for arbitrary qudit states including a single qudit and discuss entangled single qudit state. We consider in detail the examples of N = 3 and 4. Also we point out the possible use of entangled states of systems without subsystems (e.g., a single qudit) as a resource for quantum computations.  相似文献   

19.
The subject of the article is aspects of PV modules and cells measurement, with the use of natural sunlight. A light source is an important element during calibration and measurements of solar cells and modules. All designers of artificial light sources try to recreate natural light using so called measurement tables. The correctly performed measurement, i.e. meeting all the appropriate atmospheric conditions, guarantees obtaining the result with the use of a reference spectrum. The article has two main aims. The first aim of the article is to answer the question asked earlier - if the sunlight spectrum registered in appropriate conditions is so good that it serves as the reference spectrum - then, in practice, during measurements carried out with its use, certain problems occur regarding the correct measurement results or their interpretation. The second aim regards presenting detailed numeric procedures in order to enable readers to associate air mass with geographical coordinates and Local Solar Time of their study/laboratory location. Moreover, having the data from their local meteorological station, they will be able to estimate the occurrence of the measurement spectral error of the tested cell/module not only from the group referred to in the article but also for others, for which they have a dedicated characteristics of spectral response.  相似文献   

20.
It is shown that spin Calogero–Moser systems are completely integrable in a sense of degenerate integrability. Their Liouville tori have dimension less than half of the dimension of the phase space. It is also shown that rational spin Ruijsenaars systems are degenerately integrable and dual to spin Calogero–Moser systems in a sense that action-angle variables of one are angle-action variables of the other.  相似文献   

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