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arXiv · astro-ph/0501318

Dark Matter in a One-dimensional Universe

Costantino Sigismondi
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Abstract

A computer code to simulate temporal evolution of overdensities in a one-dimensional Universe is presented for didactic purposes. The formation of large scale structures in this one-dimensional universe can be studied both in matter or radiation dominated eras. Since large scale structures are already observed at z > 7, primordial dark matter overdensities delta_DM which are 90 times larger than the observed barionic delta_B in the cosmic microwave background are required at z~1000. This makes possible non-linear gravitational collapse at redshift z >7 and the formation of the structures. Primordial perturbations delta_B~10^-5 do not leave the linear regime of growth without the aid of dark matter's potential wells. This code is suitable for commercial worksheets like MSExcel, StarOffice, or OpenOffice.

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Costantino Sigismondi. 2005-01-15. Dark Matter in a One-dimensional Universe. https://doi.org/10.1393/ncb%2Fi2004-10037-6

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