The inverse approach to Dirac-type systems based on the $A$-function concept

Fritz Gesztesy; Alexander Sakhnovich

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arXiv · 1903.00779

The inverse approach to Dirac-type systems based on the $A$-function concept

Fritz Gesztesy·Alexander Sakhnovich

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Abstract

The principal objective in this paper is a new inverse approach to general Dirac-type systems modeled after B. Simon's 1999 inverse approach to half-line Schr\"odinger operators. In particular, we derive the so-called A-equation associated to Dirac-type systems and, given a fundamental positivity condition, we prove that this integro-differential equation for A is uniquely solvable. We show how to recover the matrix-valued potential coefficient from A. This approach is also applicable to matrix-valued Schr\"odinger operators on a half-line.

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BibTeX RIS

Fritz Gesztesy, Alexander Sakhnovich. 2019-03-02. The inverse approach to Dirac-type systems based on the $A$-function concept. https://arxiv.org/abs/1903.00779

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