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arXiv · 0904.0611

Cosmological fluid dynamics in the Schrödinger formalism

Rebecca Johnston·A. N. Lasenby·M. P. Hobson
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Abstract

We investigate the dynamics of a cosmological dark matter fluid in the Schrödinger formulation, seeking to evaluate the approach as a potential tool for theorists. We find simple wave-mechanical solutions of the equations for the cosmological homogeneous background evolution of the dark matter field, and use them to obtain a piecewise analytic solution for the evolution of a compensated spherical overdensity. We analyse this solution from a `quantum mechanical' viewpoint, and establish the correct boundary conditions satisfied by the wavefunction. Using techniques from multi-particle quantum mechanics, we establish the equations governing the evolution of multiple fluids and then solve them numerically in such a system. Our results establish the viability of the Schrödinger formulation as a genuine alternative to standard methods in certain contexts, and a novel way to model multiple fluids.

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Rebecca Johnston, A. N. Lasenby, M. P. Hobson. 2009-04-03. Cosmological fluid dynamics in the Schrödinger formalism. https://arxiv.org/abs/0904.0611

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