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On Higher-Order Szegő Theorems with a Single Critical Point of Arbitrary Order

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Abstract

We prove the following higher-order Szegő theorem: If a measure on the unit circle has absolutely continuous part \(w(\theta )\) and Verblunsky coefficients \(\alpha \) with square-summable variation, then for any positive integer m,

is finite if and only if \(\alpha \in \ell ^{2m+2}\). This is the first known equivalence result of this kind in the regime of very slow decay, i.e., with \(\ell ^p\) conditions with arbitrarily large p. The usual difficulty of controlling higher-order sum rules is avoided by a new test sequence approach.

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References

  1. Cantero, M.J., Moral, L., Velázquez, L.: Five-diagonal matrices and zeros of orthogonal polynomials on the unit circle. Linear Algebra Appl. 362, 29–56 (2003)

    Article  MathSciNet  MATH  Google Scholar 

  2. Deift, P., Killip, R.: On the absolutely continuous spectrum of one-dimensional Schrödinger operators with square summable potentials. Commun. Math. Phys. 203(2), 341–347 (1999)

    Article  MathSciNet  MATH  Google Scholar 

  3. Denisov, S.A.: On a conjecture by Y. Last. J. Approx. Theory 158(2), 194–213 (2009)

    Article  MathSciNet  MATH  Google Scholar 

  4. Golinskii, L., Zlatoš, A.: Coefficients of orthogonal polynomials on the unit circle and higher-order Szegő theorems. Constr. Approx. 26(3), 361–382 (2007)

    Article  MathSciNet  MATH  Google Scholar 

  5. Kaluzhny, U., Shamis, M.: Preservation of absolutely continuous spectrum of periodic Jacobi operators under perturbations of square-summable variation. Constr. Approx. 35(1), 89–105 (2012)

    Article  MathSciNet  MATH  Google Scholar 

  6. Killip, R., Simon, B.: Sum rules for Jacobi matrices and their applications to spectral theory. Ann. of Math. (2) 158(1), 253–321 (2003)

    Article  MathSciNet  MATH  Google Scholar 

  7. Killip, R., Simon, B.: Sum rules and spectral measures of Schrödinger operators with \(L^2\) potentials. Ann. of Math. (2) 170(2), 739–782 (2009)

    Article  MathSciNet  MATH  Google Scholar 

  8. Kreimer, Y., Last, Y., Simon, B.: Monotone Jacobi parameters and non-Szegő weights. J. Approx. Theory 157, 144–171 (2009)

    Article  MathSciNet  MATH  Google Scholar 

  9. Kupin, S.: On a spectral property of Jacobi matrices. Proc. Am. Math. Soc. 132(5), 1377–1383 (2004)

    Article  MathSciNet  MATH  Google Scholar 

  10. Kupin, S.: Spectral properties of Jacobi matrices and sum rules of special form. J. Funct. Anal. 227(1), 1–29 (2005)

    Article  MathSciNet  MATH  Google Scholar 

  11. Laptev, A., Naboko, S., Safronov, O.: On new relations between spectral properties of Jacobi matrices and their coefficients. Commun. Math. Phys. 241(1), 91–110 (2003)

    Article  MathSciNet  MATH  Google Scholar 

  12. Lukic, M.: Square-summable variation and absolutely continuous spectrum, J. Spectr. Theory, to appear. arXiv:1303.4161

  13. Lukic, M.: Orthogonal polynomials with recursion coefficients of generalized bounded variation. Commun. Math. Phys. 306(2), 485–509 (2011)

    Article  MathSciNet  MATH  Google Scholar 

  14. Lukic, M.: On a conjecture for higher-order Szegő theorems. Constr. Approx. 38, 161–169 (2013). arXiv:1210.6953

    Article  MathSciNet  MATH  Google Scholar 

  15. Molchanov, S., Novitskii, M., Vainberg, B.: First KdV integrals and absolutely continuous spectrum for 1-D Schrödinger operator. Commun. Math. Phys. 216(1), 195–213 (2001)

    Article  MathSciNet  MATH  Google Scholar 

  16. Nazarov, F., Peherstorfer, F., Volberg, A., Yuditskii, P.: On generalized sum rules for Jacobi matrices. Int. Math. Res. Notes 3, 155–186 (2005)

    Article  MathSciNet  MATH  Google Scholar 

  17. Peherstorfer, F., Steinbauer, R.: Orthogonal polynomials on the circumference and arcs of the circumference. J. Approx. Theory 102(1), 96–119 (2000)

    Article  MathSciNet  MATH  Google Scholar 

  18. Rakhmanov, E.A.: On the asymptotics of the ratio of orthogonal polynomials, ii. Math. USSR 46, 105–117 (1983)

    Article  MATH  Google Scholar 

  19. Simon, B.: Orthogonal polynomials on the unit circle. Part 1, American Mathematical Society Colloquium Publications, vol. 54, American Mathematical Society, Providence, RI, (2005), Classical theory

  20. Simon, B.: Orthogonal polynomials on the unit circle. Part 2, American Mathematical Society Colloquium Publications, vol. 54, American Mathematical Society, Providence, RI, (2005), Spectral theory

  21. Simon, B., Zlatoš, A.: Higher-order Szegő theorems with two singular points. J. Approx. Theory 134(1), 114–129 (2005)

    Article  MathSciNet  MATH  Google Scholar 

  22. Szegő, G.: Beiträge zur Theorie der Toeplitzschen Formen. Math. Z. 6(3–4), 167–202 (1920)

    Article  MathSciNet  MATH  Google Scholar 

  23. Szegő, G.: Beiträge zur Theorie der Toeplitzschen Formen. Math. Z. 9(3–4), 167–190 (1921)

    Article  MathSciNet  MATH  Google Scholar 

  24. Verblunsky, S.: On positive harmonic functions: a contribution to the algebra of Fourier series. Proc. Lond. Math. Soc. S2–38(1), 125–157 (1935)

    Article  MathSciNet  MATH  Google Scholar 

  25. Verblunsky, S.: On positive harmonic functions (second paper). Proc. Lond. Math. Soc. 40, 290–320 (1936)

    Article  MathSciNet  MATH  Google Scholar 

  26. Weidmann, J.: Zur Spektraltheorie von Sturm-Liouville-Operatoren. Math. Z. 98, 268–302 (1967)

    Article  MathSciNet  MATH  Google Scholar 

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Correspondence to Milivoje Lukic.

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Communicated by Vilmos Totik.

The author was partially supported by NSF Grant DMS-1301582.

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Lukic, M. On Higher-Order Szegő Theorems with a Single Critical Point of Arbitrary Order. Constr Approx 44, 283–296 (2016). https://doi.org/10.1007/s00365-015-9320-4

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  • DOI: https://doi.org/10.1007/s00365-015-9320-4

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