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arXiv · 2001.11765

Scalar Klein--Gordon equation and its analytically continued dispersion diagram

A. I. Korolkov·A. V. Shanin
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Abstract

The scalar Klein-Gordon equation describes wave motion in a waveguide with a cut-off. For example, the displacement of an elastic cord anchored to a solid base by elastic elements can be described by the scalar Klein-Gordon equation. We analyse this equation using the concept of analytical continuation of dispersion diagram. Particularly, it is shown that the dispersion diagram is topologically equivalent to a tube analytically embedded in two-dimensional complex space. The corresponding Fourier integral is studied on this tube using the Cauchy's theorem. The basic properties of the scalar Klein-Gordon equation are established.

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A. I. Korolkov, A. V. Shanin. 2020-01-31. Scalar Klein--Gordon equation and its analytically continued dispersion diagram. https://arxiv.org/abs/2001.11765

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