Committee Chair
Nichols, Roger A.
Committee Member
Barioli, Francesco; Belinskiy, Boris P.; van der Merwe, Lucas C.
College
College of Arts and Sciences
Publisher
University of Tennessee at Chattanooga
Place of Publication
Chattanooga (Tenn.)
Abstract
We consider self-adjoint extensions of the minimal operator generated by the differential expression $\cL = - d^2/dx^2+V$ on the half-line $[0,\infty)$, where $V$ is a real-valued function integrable with respect to the weight $1+x$. The self-adjoint extensions are of Schr\"odinger-type and form a one-parameter family formally given by $H_{\alpha}=-d^2/dx^2+V$, $\alpha\in[0,\pi)$, with the boundary condition $\sin(\alpha)f'(0) = \cos(\alpha)f(0)$ at $x=0$. We derive a formula that relates the resolvent operator of $H_{\alpha}$ to the resolvent operator of $H_0$ in terms of the Jost solution corresponding to the underlying differential equation $\mathcal{L}u=zu$. Combining this resolvent formula and properties of the Jost solution, we compute the trace of the difference of the resolvents of $H_{\alpha}$ and the free operator $H_{\alpha}^{(0)}$ with $V\equiv 0$ in terms of the parameter $\alpha$ and the Jost function for $\cL u=zu$.
Acknowledgments
I am grateful to the Department of Mathematics of the University of Tennessee at Chattanooga for the support and numerous experiences it has given me. I would especially like to thank my advisor, Roger Nichols, for his guidance during my time in graduate school and, in particular, throughout the research process.
Degree
M. S.; A thesis submitted to the faculty of the University of Tennessee at Chattanooga in partial fulfillment of the requirements of the degree of Master of Science.
Date
5-2017
Subject
Differential operators; Schrödinger operator; Operator theory; Kreĭn spaces; Differential equations
Document Type
Masters theses
DCMI Type
Text
Extent
vi, 54 leaves
Language
English
Rights
https://rightsstatements.org/page/InC/1.0/?language=en
License
http://creativecommons.org/licenses/by/3.0/
Recommended Citation
Sofo, Philip C., "Krein's identity and trace formulas for half-line Schrodinger operators" (2017). Masters Theses and Doctoral Dissertations.
https://scholar.utc.edu/theses/495
Department
Dept. of Mathematics