Asymptotics of Laurent Polynomials of Even Degree Orthogonal with Respect to Varying Exponential Weights
| dc.creator | McLaughlin, K. T. -R. | |
| dc.creator | Vartanian, A. H. | |
| dc.creator | Zhou, X. | |
| dc.date | 2006-01-13 | |
| dc.date.accessioned | 2026-07-07T06:58:52Z | |
| dc.date.available | 2026-07-07T06:58:52Z | |
| dc.description | Let $Λ^{\mathbb{R}}$ denote the linear space over $\mathbb{R}$ spanned by $z^{k}$, $k \! \in \! \mathbb{Z}$. Define the real inner product (with varying exponential weights) $\langle \boldsymbol{\cdot},\boldsymbol{\cdot} \rangle_{\mathscr{L}} \colon Λ^{\mathbb{R}} \times Λ^{\mathbb{R}} \! \to \! \mathbb{R}$, $(f,g) \! \mapsto \! \int_{\mathbb{R}}f(s)g(s) \exp (-\mathscr{N} \, V(s)) \, ds$, $\mathscr{N} \! \in \! \mathbb{N}$, where the external field $V$ satisfies: (i) $V$ is real analytic on $\mathbb{R} \setminus \{0\}$; (ii) $\lim_{\vert x \vert \to \infty}(V(x)/\ln (x^{2} \! + \! 1)) \! = \! +\infty$; and (iii) $\lim_{\vert x \vert \to 0}(V(x)/\ln (x^{-2} \! + \! 1)) \! = \! +\infty$. Orthogonalisation of the (ordered) base $\lbrace 1,z^{-1},z,z^{-2},z^{2},\dotsc,z^{-k},z^{k},\dotsc \rbrace$ with respect to $\langle \boldsymbol{\cdot},\boldsymbol{\cdot} \rangle_{\mathscr{L}}$ yields the even degree and odd degree orthonormal Laurent polynomials $\lbrace ϕ_{m}(z) \rbrace_{m=0}^{\infty}$: $ϕ_{2n}(z) \! = \! ξ^{(2n)}_{-n} z^{-n} \! + \! \dotsb \! + \! ξ^{(2n)}_{n}z^{n}$, $ξ^{(2n)}_{n} \! > \! 0$, and $ϕ_{2n+1}(z) \! = \! ξ^{(2n+1)}_{-n-1}z^{-n-1} \! + \! \dotsb \! + \! ξ^{(2n+1)}_{n}z^{n}$, $ξ^{(2n+1)}_{-n-1} \! > \! 0$. Asymptotics in the double-scaling limit as $\mathscr{N},n \! \to \! \infty$ such that $\mathscr{N}/n \! = \! 1 \! + \! o(1)$ of $ξ^{(2n)}_{n}$ and $ϕ_{2n} (z)$ (in the entire complex plane) are obtained by formulating the even degree orthonormal Laurent polynomial problem as a matrix Riemann-Hilbert problem on $\mathbb{R}$, and then extracting the large-$n$ behaviour by applying the Deift-Zhou non-linear steepest-descent method in conjunction with the extension of Deift-Venakides-Zhou. | |
| dc.identifier | https://arxiv.org/abs/math/0601306 | |
| dc.identifier | http://arxiv.org/abs/math/0601306 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/107530 | |
| dc.subject | Classical Analysis and ODEs | |
| dc.subject | Mathematical Physics | |
| dc.subject | 30E20, 30E25, 42C05, 45E05, 47B36 (Primary); 30C15, 30C70, 30E05, 30E10, 31A99, 41A20, 41A21, 41A60 (Secondary) | |
| dc.title | Asymptotics of Laurent Polynomials of Even Degree Orthogonal with Respect to Varying Exponential Weights | |
| dc.type | text |