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arXiv · hep-th/9308082

Path Integral Discussion of Two and- Three-Dimensional $δ$-Function Perturbations

Christian Grosche
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Abstract

The incorporation of two- and three-dimensional $δ$-function perturbations into the path-integral formalism is discussed. In contrast to the one-dimensional case, a regularization procedure is needed due to the divergence of the Green-function $G^{(V)}(\vec x,\vec y;E)$, ($\vec x,\vec y\in\bbbr^2,\bbbr^3$) for $\vec x=\vec y$, corresponding to a potential problem $V(\vec x)$. The known procedure to define proper self-adjoint extensions for Hamiltonians with deficiency indices can be used to regularize the path integral, giving a perturbative approach for $δ$-function perturbations in two and three dimensions in the context of path integrals. Several examples illustrate the formalism.

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Christian Grosche. 1993-08-17. Path Integral Discussion of Two and- Three-Dimensional $δ$-Function Perturbations. https://doi.org/10.1002/andp.19945060406

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