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arXiv · 1904.01061

Approximation of one-dimensional relativistic point interactions by regular potentials revised

Matěj Tušek
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Abstract

We show that the one-dimensional Dirac operator with quite general point interaction may be approximated in the norm resolvent sense by the Dirac operator with a scaled regular potential of the form $1/\varepsilon~h(x/\varepsilon)\otimes B$, where $B$ is a suitable $2\times 2$ matrix. Moreover, we prove that the limit does not depend on the particular choice of $h$ as long as it integrates to a constant value.

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Matěj Tušek. 2019-04-01. Approximation of one-dimensional relativistic point interactions by regular potentials revised. https://doi.org/10.1007/s11005-020-01325-6

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