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Using Perturbative Least Action to Recover Cosmological Initial Conditions

David M. Goldberg·David N. Spergel
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Abstract

We introduce a new method for generating initial conditions consistent with highly nonlinear observations of density and velocity fields. Using a variant of the Least Action method, called Perturbative Least Action (PLA), we show that it is possible to generate several different sets of initial conditions, each of which will satisfy a set of highly nonlinear observational constraints at the present day. We then discuss a code written to test and apply this method and present the results of several simulations.

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David M. Goldberg, David N. Spergel. 2000-04-17. Using Perturbative Least Action to Recover Cosmological Initial Conditions. https://doi.org/10.1086/317182

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