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arXiv · 2210.04004

Beyond relativistic Lagrangian perturbation theory. I. An exact-solution controlled model for structure formation

Ismael Delgado Gaspar·Thomas Buchert·Jan J. Ostrowski
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Abstract

We develop a new nonlinear method to model structure formation in general relativity from a generalization of the relativistic Lagrangian perturbation schemes, controlled by Szekeres (and LTB) exact solutions. The overall approach can be interpreted as the evolution of a deformation field on an inhomogeneous reference model, obeying locally Friedmann-like equations. In the special case of locally one-dimensional deformations, the new model contains the entire Szekeres family of exact solutions. As thus formulated, this approach paraphrases the Newtonian and relativistic Zel'dovich approximations, having a large potential for applications in contexts where relativistic degrees of freedom are relevant. Numerical simulations are implemented to illustrate the capabilities and accuracy of the model.

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Ismael Delgado Gaspar, Thomas Buchert, Jan J. Ostrowski. 2023-01-18. Beyond relativistic Lagrangian perturbation theory. I. An exact-solution controlled model for structure formation. https://doi.org/10.1103/physrevd.107.024018

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