Abstract
We consider discrete Dirac systems as an approach to the study of the corresponding block Toeplitz matrices, which in many ways completes the famous approach via Szegő recurrences and matrix orthogonal polynomials. We prove an analog of the Christoffel–Darboux formula and derive the asymptotic relations for the analog of reproducing kernel (using Weyl–Titchmarsh functions of discrete Dirac systems). These asymptotic relations are expressed also in terms of block Toeplitz matrices. We study the case of rational Weyl–Titchmarsh functions (and GBDT version of the Bäcklund–Darboux transformation of the trivial discrete Dirac system) as well. It is shown that block diagonal plus block semi-separable Toeplitz matrices (which are easily inverted) appear in this case.
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Álvarez-Fernández, C., Ariznabarreta, G., García-Ardila, J.C., Mañas, M., Marcellán, F.: Christoffel transformations for matrix orthogonal polynomials in the real line and the non-Abelian 2D Toda lattice hierarchy. Int. Math. Res. Not. IMRN 2017, 1285–1341 (2017)
Aptekarev, A.I., Nikishin, E.M.: The scattering problem for a discrete Sturm–Liouville operator. Math. USSR Sb. 49, 325–355 (1984)
Arov, D.Z., Krein, M.G.: Problem of search of the minimum of entropy in indeterminate extension problems. Funct. Anal. Appl. 15, 123–126 (1981)
Breuer, J., Duits, M.: Central limit theorems for biorthogonal ensembles and asymptotics of recurrence coefficients. J. Am. Math. Soc. 30, 27–66 (2017)
Breuer, J., Last, Y., Simon, B.: Stability of asymptotics of Christoffel–Darboux kernels. Comm. Math. Phys. 330, 1155–1178 (2014)
Cieslinski, J.L.: Algebraic construction of the Darboux matrix revisited. J. Phys. A 42, Paper 404003 (2009)
Daems, E., Kuijlaars, A.B.J.: A Christoffel–Darboux formula for multiple orthogonal polynomials. J. Approx. Theory 130, 190–202 (2004)
Damanik, D., Pushnitski, A., Simon, B.: The analytic theory of matrix orthogonal polynomials. Surv. Approx. Theory 4, 1–85 (2008)
Delsarte, Ph., Genin, Y.V., Kamp, Y.G.: Orthogonal polynomial matrices on the unit circle. IEEE Trans. Circuits Syst. CAS-2, 149–160 (1978)
Eidelman, Y., Gohberg, I.: Algorithms for inversion of diagonal plus semiseparable operator matrices. Integral Equ. Oper. Theory 44, 172–211 (2002)
Fritzsche, B., Kirstein, B., Roitberg, I., Sakhnovich, A.L.: Weyl matrix functions and inverse problems for discrete Dirac-type self-adjoint systems: explicit and general solutions. Oper. Matrices 2, 201–231 (2008)
Fritzsche, B., Kirstein, B., Roitberg, I., Sakhnovich, A.L.: Discrete Dirac systems on the semiaxis: rational reflection coefficients and Weyl functions. J. Differ. Equ. Appl. 25, 294–304 (2019)
Gesztesy, F., Teschl, G.: On the double commutation method. Proc. Am. Math. Soc. 124, 1831–1840 (1996)
Gohberg, I., Kailath, T., Koltracht, I.: Linear complexity algorithms for semiseparable matrices. Integral Equ. Operator Theory 8, 780–804 (1985)
Golinskii, L., Nevai, P.: Szegö difference equations, transfer matrices and orthogonal polynomials on the unit circle. Commun. Math. Phys. 223, 223–259 (2001)
Groenevelt, W., Koelink, E.A.: A hypergeometric function transform and matrix-valued orthogonal polynomials. Constr. Approx. 38, 277–309 (2013)
Gu, C., Hu, H., Zhou, X.: Darboux Transformations in Integrable Systems. Springer, Dordrecht (2005)
Helson, H., Lowdenslager, D.: Prediction theory and Fourier series in several variables. Acta Math. 99, 165–202 (1958)
Kaashoek, M.A., Sakhnovich, A.L.: Discrete skew self-adjoint canonical system and the isotropic Heisenberg magnet model. J. Funct. Anal. 228, 207–233 (2005)
Katsnelson, V.E., Kirstein, B.: On the theory of matrix-valued functions belonging to the Smirnov class. In: Oper. Theory Adv. Appl. 95, pp. 299–350. Birkhäuser, Basel (1997)
Kostenko, A., Sakhnovich, A., Teschl, G.: Commutation Methods for Schrödinger Operators with Strongly Singular Potentials. Math. Nachr. 285, 392–410 (2012)
Lubinsky, D.S.: A new approach to universality limits involving orthogonal polynomials. Ann. Math. 170, 915–939 (2009)
Makarov, N., Poltoratski, A.: Beurling-Malliavin theory for Toeplitz kernels. Invent. Math. 180, 443–480 (2010)
Matveev, V.B., Salle, M.A.: Darboux Transformations and Solitons. Springer, Berlin (1991)
Masani, P., Wiener, N.: On bivariate stationary processes and the factorization of matrix-valued functions. Theor. Probab. Appl. 4, 300–308 (1959)
Nevai, P., Freud, G.: Orthogonal polynomials and Christoffel functions. A case study. J. Approx. Theory 48, 3–167 (1986)
Nevai, P., Totik, V.: Christoffel functions for weights with jumps. Constr. Approx. 42, 265–280 (2015)
Privalov, I.I.: Boundary Properties of Analytic Functions. VEB Deutscher Verlag Wiss, Berlin (1956)
Roitberg, I., Sakhnovich, A.L.: The discrete self-adjoint Dirac systems of general type: explicit solutions of direct and inverse problems, asymptotics of Verblunsky-type coefficients and the stability of solving of the inverse problem. Zh. Mat. Fiz. Anal. Geom. 14, 532–548 (2018)
Rosenblum, M., Rovnyak, J.: Topics in Hardy Classes and Univalent Functions. Birkhäuser, Basel (1994)
Rozanov, Yu.A.: Spectral properties of multivariate stationary processes and boundary properties of analytic matrices. Theory Probab. Appl. 5, 362–376 (1960)
Sakhnovich, A.L.: On a class of extremal problems. USSR-Izv. 30, 411–418 (1988)
Sakhnovich, A.L.: New “Verblunsky-type’’ coefficients of block Toeplitz and Hankel matrices and of corresponding Dirac and canonical systems. J. Approx. Theory 237, 186–209 (2019)
Sakhnovich, A.L., Sakhnovich, L.A., Roitberg, I.. Ya..: Inverse Problems and Nonlinear Evolution Equations. Solutions, Darboux Matrices and Weyl-Titchmarsh Functions. De Gruyter, Berlin (2013)
Sakhnovich, L.A.: On the factorization of the transfer matrix function. Sov. Math. Dokl. 17, 203–207 (1976)
Sakhnovich, L.A.: Interpolation Theory and Its Applications. Kluwer, Dordrecht (1997)
Sakhnovich, L.A.: Spectral Theory of Canonical Differential Systems, Method of Operator Identities. Birkhäuser, Basel (1999)
Sakhnovich, L.A.: Levy Processes, Integral Equations, Statistical Physics: Connections and Interactions. Birkhäuser/Springer Basel AG, Basel (2012)
Simon, B.: Analogs of the m-function in the theory of orthogonal polynomials on the unit circle. J. Comput. Appl. Math. 171, 411–424 (2004)
van Assche, W.: Orthogonal Polynomials and Painleve Equations. Cambridge University Press, Cambridge (2018)
Vandebril, R., Van Barel, M., Golub, G., Mastronardi, N.: A bibliography on semiseparable matrices. Calcolo 42, 249–270 (2005)
Vladimirov, V.S., Volovich, I.V.: The diophantine moment problem, orthogonal polynomials and some models of statistical physics. In: Lect. Notes in Math. 1043, pp. 289–292. Springer, Berlin (1984)
Wiener, N.: On the factorization of matrices. Comment. Math. Helv. 29, 97–111 (1955)
Zakharov, V.E., Mikhailov, A.V.: On the integrability of classical spinor models in two-dimensional space-time. Commun. Math. Phys. 74, 21–40 (1980)
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This research was supported by the Austrian Science Fund (FWF) under Grant No. P29177.
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Sakhnovich, A. Discrete Self-adjoint Dirac Systems: Asymptotic Relations, Weyl Functions and Toeplitz Matrices. Constr Approx 55, 641–659 (2022). https://doi.org/10.1007/s00365-021-09530-9
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DOI: https://doi.org/10.1007/s00365-021-09530-9
Keywords
- Discrete canonical system
- Block Toeplitz matrix
- Weight factorisation
- Asymptotics of reproducing kernel
- Bäcklund–Darboux transformation