264 research outputs found

    Symplectic areas, quantization, and dynamics in electromagnetic fields

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    A gauge invariant quantization in a closed integral form is developed over a linear phase space endowed with an inhomogeneous Faraday electromagnetic tensor. An analog of the Groenewold product formula (corresponding to Weyl ordering) is obtained via a membrane magnetic area, and extended to the product of N symbols. The problem of ordering in quantization is related to different configurations of membranes: a choice of configuration determines a phase factor that fixes the ordering and controls a symplectic groupoid structure on the secondary phase space. A gauge invariant solution of the quantum evolution problem for a charged particle in an electromagnetic field is represented in an exact continual form and in the semiclassical approximation via the area of dynamical membranes.Comment: 39 pages, 17 figure

    Analogues of the central point theorem for families with dd-intersection property in Rd\mathbb R^d

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    In this paper we consider families of compact convex sets in Rd\mathbb R^d such that any subfamily of size at most dd has a nonempty intersection. We prove some analogues of the central point theorem and Tverberg's theorem for such families

    Cotangent bundle quantization: Entangling of metric and magnetic field

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    For manifolds M\cal M of noncompact type endowed with an affine connection (for example, the Levi-Civita connection) and a closed 2-form (magnetic field) we define a Hilbert algebra structure in the space L2(TM)L^2(T^*\cal M) and construct an irreducible representation of this algebra in L2(M)L^2(\cal M). This algebra is automatically extended to polynomial in momenta functions and distributions. Under some natural conditions this algebra is unique. The non-commutative product over TMT^*\cal M is given by an explicit integral formula. This product is exact (not formal) and is expressed in invariant geometrical terms. Our analysis reveals this product has a front, which is described in terms of geodesic triangles in M\cal M. The quantization of δ\delta-functions induces a family of symplectic reflections in TMT^*\cal M and generates a magneto-geodesic connection Γ\Gamma on TMT^*\cal M. This symplectic connection entangles, on the phase space level, the original affine structure on M\cal M and the magnetic field. In the classical approximation, the 2\hbar^2-part of the quantum product contains the Ricci curvature of Γ\Gamma and a magneto-geodesic coupling tensor.Comment: Latex, 38 pages, 5 figures, minor correction

    Tverberg-type theorems for intersecting by rays

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    In this paper we consider some results on intersection between rays and a given family of convex, compact sets. These results are similar to the center point theorem, and Tverberg's theorem on partitions of a point set

    Quantum Magnetic Algebra and Magnetic Curvature

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    The symplectic geometry of the phase space associated with a charged particle is determined by the addition of the Faraday 2-form to the standard structure on the Euclidean phase space. In this paper we describe the corresponding algebra of Weyl-symmetrized functions in coordinate and momentum operators satisfying nonlinear commutation relations. The multiplication in this algebra generates an associative product of functions on the phase space. This product is given by an integral kernel whose phase is the symplectic area of a groupoid-consistent membrane. A symplectic phase space connection with non-trivial curvature is extracted from the magnetic reflections associated with the Stratonovich quantizer. Zero and constant curvature cases are considered as examples. The quantization with both static and time dependent electromagnetic fields is obtained. The expansion of the product by the deformation parameter, written in the covariant form, is compared with the known deformation quantization formulas.Comment: 23 page

    Method for the rapid temperature correction of a transmission in an inhomogeneous atmosphere

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    The value of the transmission function in a heterogeneous atmosphere is determined by iterative correction of values in particular layers. The iterative equation and a set of absolute values of errors is presented in two tables

    Infinitesimal deformations of a formal symplectic groupoid

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    Given a formal symplectic groupoid GG over a Poisson manifold (M,π0)(M, \pi_0), we define a new object, an infinitesimal deformation of GG, which can be thought of as a formal symplectic groupoid over the manifold MM equipped with an infinitesimal deformation π0+ϵπ1\pi_0 + \epsilon \pi_1 of the Poisson bivector field π0\pi_0. The source and target mappings of a deformation of GG are deformations of the source and target mappings of GG. To any pair of natural star products (,~)(\ast, \tilde\ast) having the same formal symplectic groupoid GG we relate an infinitesimal deformation of GG. We call it the deformation groupoid of the pair (,~)(\ast, \tilde\ast). We give explicit formulas for the source and target mappings of the deformation groupoid of a pair of star products with separation of variables on a Kaehler- Poisson manifold. Finally, we give an algorithm for calculating the principal symbols of the components of the logarithm of a formal Berezin transform of a star product with separation of variables. This algorithm is based upon some deformation groupoid.Comment: 22 pages, the paper is reworked, new proofs are adde

    A note on Makeev's conjectures

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    A counterexample is given for the Knaster-like conjecture of Makeev for functions on S2S^2. Some particular cases of another conjecture of Makeev, on inscribing a quadrangle into a smooth simple closed curve, are solved positively

    Weyl's symbols of Heisenberg operators of canonical coordinates and momenta as quantum characteristics

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    The knowledge of quantum phase flow induced under the Weyl's association rule by the evolution of Heisenberg operators of canonical coordinates and momenta allows to find the evolution of symbols of generic Heisenberg operators. The quantum phase flow curves obey the quantum Hamilton's equations and play the role of characteristics. At any fixed level of accuracy of semiclassical expansion, quantum characteristics can be constructed by solving a coupled system of first-order ordinary differential equations for quantum trajectories and generalized Jacobi fields. Classical and quantum constraint systems are discussed. The phase-space analytic geometry based on the star-product operation can hardly be visualized. The statement "quantum trajectory belongs to a constraint submanifold" can be changed e.g. to the opposite by a unitary transformation. Some of relations among quantum objects in phase space are, however, left invariant by unitary transformations and support partly geometric relations of belonging and intersection. Quantum phase flow satisfies the star-composition law and preserves hamiltonian and constraint star-functions.Comment: 27 pages REVTeX, 6 EPS Figures. New references added. Accepted for publication to JM
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