THESIS - Roozbeh Gharakhloo (1).pdf (984.16 kB)

# Asymptotic Analysis of Structured Determinants via the Riemann-Hilbert Approach

In this work we use and develop Riemann-Hilbert techniques to study the asymptotic behavior of structured determinants. In chapter one we will review the main underlying

definitions and ideas which will be extensively used throughout the thesis. Chapter two is devoted to the asymptotic analysis of Hankel determinants with Laguerre-type and Jacobi-type potentials with Fisher-Hartwig singularities. In chapter three we will propose a Riemann-Hilbert problem for Toeplitz+Hankel determinants. We will then analyze this Riemann-Hilbert problem for a certain family of Toeplitz and Hankel symbols. In Chapter four we will study the asymptotics of a certain bordered-Toeplitz determinant which is related to the next-to-diagonal correlations of the anisotropic Ising model. The analysis is based upon relating the bordered-Toeplitz determinant to the solution of the Riemann-Hilbert problem associated to pure Toeplitz determinants. Finally in chapter ve we will study the emptiness formation probability in the XXZ-spin 1/2 Heisenberg chain, or equivalently, the asymptotic analysis of the associated Fredholm determinant.

## Funding

### DMS-1700261

## History

## Degree Type

- Doctor of Philosophy

## Department

- Mathematics

## Campus location

- Indianapolis

## Advisor/Supervisor/Committee Chair

Alexander Its## Additional Committee Member 2

Pavel Bleher## Additional Committee Member 3

Maxim Yattselev## Additional Committee Member 4

Alexandre Eremenko## Usage metrics

## Categories

## Keywords

Riemann-Hilbert problemsorthogonal polynomialsHankel determinantsToeplitz determinantsToeplitz+Hankel determinantsBordered-Toeplitz determinantsIsing modelEmptiness formation probabilityIntegrable integral operatorsHeisenberg spin chainMathematical Physics not elsewhere classifiedIntegrable Systems (Classical and Quantum)Approximation Theory and Asymptotic Methods