English

Shannon entropy of symmetric Pollaczek polynomials

Classical Analysis and ODEs 2007-05-23 v1 Mathematical Physics math.MP

Abstract

We discuss the asymptotic behavior (as nn\to \infty) of the entropic integrals En=11log(pn2(x))pn2(x)w(x)dx, E_n= - \int_{-1}^1 \log \big(p^2_n(x) \big) p^2_n(x) w(x) d x, and Fn=11log(pn2(x)w(x))pn2(x)w(x)dx, F_n = -\int_{-1}^1 \log (p_n^2(x)w(x)) p_n^2(x) w(x) dx, when ww is the symmetric Pollaczek weight on [1,1][-1,1] with main parameter λ1\lambda\geq 1, and pnp_n is the corresponding orthonormal polynomial of degree nn. It is well known that ww does not belong to the Szeg\H{o} class, which implies in particular that EnE_n\to -\infty. For this sequence we find the first two terms of the asymptotic expansion. Furthermore, we show that Fnlog(π)1F_n \to \log (\pi)-1, proving that this ``universal behavior'' extends beyond the Szeg\H{o} class. The asymptotics of EnE_n has also a curious interpretation in terms of the mutual energy of two relevant sequences of measures associated with pnp_n's.

Keywords

Cite

@article{arxiv.math/0504250,
  title  = {Shannon entropy of symmetric Pollaczek polynomials},
  author = {A. Martinez-Finkelshtein and J. F. Sanchez-Lara},
  journal= {arXiv preprint arXiv:math/0504250},
  year   = {2007}
}

Comments

34 pages, 2 figures