Cosmological imprint of an energy component with general equation of state

  title={Cosmological imprint of an energy component with general equation of state},
  author={Robert R. Caldwell and R. Dave and Paul J. Steinhardt},
  journal={Physical Review Letters},
We examine the possibility that a significant component of the energy density of the Universe has an equation of state different from that of matter, radiation, or cosmological constant ({Lambda} ). An example is a cosmic scalar field evolving in a potential, but our treatment is more general. Including this component alters cosmic evolution in a way that fits current observations well. Unlike {Lambda} , it evolves dynamically and develops fluctuations, leaving a distinctive imprint on the… 

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