Adventures in Friedmann cosmology: A detailed expansion of the cosmological Friedmann equations

@article{Nemiroff2007AdventuresIF,
  title={Adventures in Friedmann cosmology: A detailed expansion of the cosmological Friedmann equations},
  author={Robert J. Nemiroff and Bijunath R. Patla},
  journal={American Journal of Physics},
  year={2007},
  volume={76},
  pages={265-276}
}
The general relativistic cosmological Friedmann equations, which describe how the scale factor of the universe evolves, are expanded explicitly to include energy forms not usually seen. The evolution of the universe as predicted by the Friedmann equations when dominated by a single, isotropic, stable, static, perfect-fluid energy form is discussed for different values of the gravitational pressure to density ratio w. These energy forms include phantom energy (w 1∕3). A brief history and… 

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