I'm trying to derive Friedmann's equation for cosmology using Newtonian physics. I've got the force equation F=ma for the case without a cosmological constant. But now I'm trying to incorporate the cosmological constant into this force equation.(adsbygoogle = window.adsbygoogle || []).push({});

But I'm having trouble seeing how the cosmological constant can appear to apply a force on some particle at the edge of a spherical universe of radius R. I thought that I might get somewhere through dimensional analysis if I could understant the units of the cosmological constant from its use in the Einstein Field Equation where it was initially introduced. But I find I don't know the units of any of the other entities in the EFE - the units for the metric gab or the Ricci tensor or the Ricci scalar or the energy-momentum tensor. Do the units change for different values of ab? It seems everyone likes using elaborate mathematics - and I don't see much practical use - not even dimensional units of the things they talk about. Any help out there? Thanks.

**Physics Forums - The Fusion of Science and Community**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Newtonian derivation of Friedmann equation

Loading...

Similar Threads for Newtonian derivation Friedmann | Date |
---|---|

B Current values for Friedman's scalar and its derivative? | Feb 20, 2018 |

A Newtonian theory of cosmological perturbations | Sep 18, 2016 |

Newtonian Friedmann Equation, Referance frame, Homogeneity | Jul 13, 2015 |

Referance Frame Calculating Newtonian Friedmann Equation | May 13, 2015 |

Newtonian cosmology vs relativistic cosmology | Apr 11, 2012 |

**Physics Forums - The Fusion of Science and Community**