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arXiv · 2508.15812

Spherical solutions to the Klein-Gordon equation in the expanding universe

Karen Yagdjian
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Abstract

We produce an explicit formula for the wave function of the spherically symmetric fields emitted to the FLRW universe with the scale factor generated by the de~Sitter universe. As an application of these explicitly written solutions of the Klein-Gordon equation, we test the decay in time of the field generated by a pionic atom.

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Karen Yagdjian. 2025-08-15. Spherical solutions to the Klein-Gordon equation in the expanding universe. https://arxiv.org/abs/2508.15812

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