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Contraction analysis establishes exponential incremental convergence of a nonlinear system by solving a linear matrix inequality for a contraction metric, and has become a standard resource for solving problems in nonlinear control and…

Dynamical Systems · Mathematics 2026-03-03 Winfried Lohmiller , Jean-Jacques Slotine

In this paper we develop a geometric approach to convex subdifferential calculus in finite dimensions with employing some ideas of modern variational analysis. This approach allows us to obtain natural and rather easy proofs of basic…

Optimization and Control · Mathematics 2015-10-06 Boris Mordukhovich , Nguyen Mau Nam

The five parameter family of multivariable Askey-Wilson polynomials is studied with four parameters generically complex. The multivariable Askey-Wilson polynomials form an orthogonal system with respect to an explicit (in general complex)…

q-alg · Mathematics 2008-02-03 Jasper V. Stokman

A method for solving cyclic block three-diagonal systems of equations is generalized for solving a block cyclic penta-diagonal system of equations. Introducing a special form of two new variables the original system is split into three…

Mathematical Software · Computer Science 2008-12-18 Milan Batista

We explicitly construct the holographic dual configuration for the four dimensional $\mathcal{N}=4$ superconformal block containing half-BPS scalar primary operators by considering its full $AdS_5 \times S^5$ dual geometry. We extend the…

High Energy Physics - Theory · Physics 2020-10-20 Heng-Yu Chen , Jun-ichi Sakamoto

We show that conformal blocks simplify greatly when there is a large difference between two of the scaling dimensions for external operators. In particular the spacetime dimension only appears in an overall constant which we determine via…

High Energy Physics - Theory · Physics 2014-09-09 Connor Behan

The N-dimensional generalization of Bertrand spaces as families of Maximally superintegrable systems on spaces with nonconstant curvature is analyzed. Considering the classification of two dimensional radial systems admitting 3 constants of…

Mathematical Physics · Physics 2015-06-15 D. Riglioni

This paper is devoted to introduce a topology on BL-algebras, makes them semitopological algebras. For any BL-algebra $\mathcal{L}=(L, \wedge, \vee, *, \to , 0, 1)$, the introduced topology is defined by a distance-like function between…

Logic · Mathematics 2022-02-25 Seyed Mohammad Amin Khatami

We introduce discrete systems in the form of straight (infinite) and ring-shaped chains, with two symmetrically placed nonlinear sites. The systems can be implemented in nonlinear optics (as waveguiding arrays) and BEC (by means of an…

Pattern Formation and Solitons · Physics 2013-07-17 Valeriy A. Brazhnyi , Boris A. Malomed

In the context of space-time block codes (STBCs), the theory of generalized quaternion and biquaternion algebras (i.e., tensor products of two quaternion algebras) over arbitrary base fields is presented, as well as quadratic form theoretic…

Information Theory · Computer Science 2012-02-07 Thomas Unger , Nadya Markin

Starting with a first order in derivatives self-dual model which describes a massive spin-4 mode in $D=2+1$ dimensions, we have obtained a sequence of three more new descriptions, which then give us an interconnected self-dual chain $SD(i)$…

High Energy Physics - Theory · Physics 2022-01-19 Elias L. Mendonça , H. L. Oliveira

In a separably connected space any two points are contained in a separable connected subset. We show a mechanism that takes a connected bounded metric space and produces a complete connected metric space whose separablewise components form…

General Topology · Mathematics 2009-03-30 T. Banakh , M. Vovk , M. R. Wójcik

We suggest two metrics for assessing the quality of atomistic configurations of disordered materials, both of which are based on quantifying the orientational distribution of neighbours around each atom in the configuration. The first…

Materials Science · Physics 2012-11-20 Matthew J. Cliffe , Andrew L. Goodwin

In this paper, we introduce properly-invariant diagonality measures of Hermitian positive-definite matrices. These diagonality measures are defined as distances or divergences between a given positive-definite matrix and its diagonal part.…

Information Theory · Computer Science 2016-09-06 Khaled Alyani , Marco Congedo , Maher Moakher

We introduce a dual-core system with double symmetry, one between the cores, and one along each core, imposed by the spatial modulation of local nonlinearity in the form of two tightly localized spots, which may be approximated by a pair of…

Pattern Formation and Solitons · Physics 2018-05-15 Krzysztof B. Zegadlo , Nguyen Viet Hung , Aleksandr Ramaniuk , Marek Trippenbach , Boris A. Malomed

We discuss the variety of coordinates often used to characterize the coherent state classical limit of an algebraic model. We show selection of appropriate coordinates naturally motivates a procedure to generate a single particle…

Chemical Physics · Physics 2007-05-23 Michael W. N. Ibrahim

A common approach to digital system design involves transforming a continuous-time (s-domain) transfer function into the discrete-time (z-domain) using methods such as Euler or Tustin. These transformations are shown to be specific cases of…

Systems and Control · Electrical Eng. & Systems 2026-05-29 Shen Chen , Yanlong Li , Jiamin Cui , Wei Yao , Jisong Wang , Yixin Tian , Chaohou Liu , Yang Yang , Jiaxi Ying , Zeng Liu , Jinjun Liu

A simplified Randall-Sundrum-like model in 6 dimensions is discussed. The extra two dimensions correspond to the cone. The effective four-dimensional scalar self-interacting theory is studied at one-loop level. The contributions due to…

General Relativity and Quantum Cosmology · Physics 2014-11-17 John Quiroga H

In critical loop models, we define diagonal boundaries as boundaries that couple to diagonal fields only. Using analytic bootstrap methods, we show that diagonal boundaries are characterised by one complex parameter, analogous to the…

High Energy Physics - Theory · Physics 2026-02-06 Max Downing , Jesper Lykke Jacobsen , Rongvoram Nivesvivat , Sylvain Ribault , Hubert Saleur

We introduce a new type of $n$-dimensional generalization of symmetric $(v,k,\lambda)$ block designs. We prove upper bounds on the dimension $n$ in terms of $v$ and $k$. We also define the corresponding concept of $n$-dimensional difference…

Combinatorics · Mathematics 2025-04-10 Vedran Krčadinac , Lucija Relić