Riemann-Hilbert analysis for Jacobi polynomials orthogonal on a single contour

Details Riemann-Hilbert analysis for Jacobi polynomials orthogonal on a single contour Riemann-Hilbert analysis for Jacobi polynomials orthogonal on a single contour

2004-10-13

arxiv.org/abs/math/0410320v1

Mathematics

Classical Analysis and ODEs

37 pages, 10 figures

Scientific paper

Classical Jacobi polynomials $P_{n}^{(\alpha,\beta)}$, with $\alpha, \beta>-1$, have a number of well-known properties, in particular the location of their zeros in the open interval $(-1,1)$. This property is no longer valid for other values of the parameters; in general, zeros are complex. In this paper we study the strong asymptotics of Jacobi polynomials where the real parameters $\alpha_n,\beta_n$ depend on $n$ in such a way that $$ \lim_{n\to\infty}\frac{\alpha_{n}}{n}=A, \quad \lim_{n\to\infty}\frac{\beta_{n}}{n}=B, $$ with $A,B \in \mathbb{R}$. We restrict our attention to the case where the limits $A,B$ are not both positive and take values outside of the triangle bounded by the straight lines A=0, B=0 and $A+B+2=0$. As a corollary, we show that in the limit the zeros distribute along certain curves that constitute trajectories of a quadratic differential. The non-hermitian orthogonality relations for Jacobi polynomials with varying parameters lie in the core of our approach; in the cases we consider, these relations hold on a single contour of the complex plane. The asymptotic analysis is performed using the Deift-Zhou steepest descent method based on the Riemann-Hilbert reformulation of Jacobi polynomials.

Affiliated with

Also associated with

No associations

Rating

Riemann-Hilbert analysis for Jacobi polynomials orthogonal on a single contour does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Riemann-Hilbert analysis for Jacobi polynomials orthogonal on a single contour, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Riemann-Hilbert analysis for Jacobi polynomials orthogonal on a single contour will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-136758