Jerk, snap, and the cosmological equation of state

  title={Jerk, snap, and the cosmological equation of state},
  author={Matt Visser},
  journal={Classical and Quantum Gravity},
  • M. Visser
  • Published 23 September 2003
  • Physics
  • Classical and Quantum Gravity
Taylor expanding the cosmological equation of state around the current epoch is the simplest model one can consider that does not make any a priori restrictions on the nature of the cosmological fluid. Most popular cosmological models attempt to be 'predictive', in the sense that once some a priori equation of state is chosen the Friedmann equations are used to determine the evolution of the FRW scale factor a(t). In contrast, a 'retrodictive' approach might usefully take observational data… 

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