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 Rahul Surendra 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… 

Figures from this paper

Cosmological consequences of a scalar field with oscillating equation of state: A possible solution to the fine-tuning and coincidence problems

  • S. Tian
  • Physics
    Physical Review D
  • 2020
We propose a new dark energy model for solving the cosmological fine-tuning and coincidence problems. A default assumption is that the fine-tuning problem disappears if we do not interpret dark

Cosmological model with dynamical cancellation of vacuum energy and dark energy

We propose a model with a compensating scalar field whose back reaction to the cosmological curvature cancels possible vacuum energy density down to the terms of the order of the time-dependent

Inhomogeneous dark energy and cosmological acceleration

We study the evolution of an inhomogeneous fluid with self-similarity of the second kind and anisotropic pressure. We found a class of solution to the Einstein field equations by assuming an equation

Perturbations in a scalar field model with virtues of ΛCDM

In the era of precision cosmology, the cosmological constant Λ gives quite an accurate description of the evolution of the Universe, but it is still plagued with the fine-tuning problem and the

Cosmology with variable parameters and effective equation of state for dark energy

A cosmological constant, Λ, is the most natural candidate to explain the origin of the dark energy (DE) component in the universe. However, due to some experimental evidence that the equation of


Our universe is observed to be accelerating due to the dominant dark energy with negative pressure. The dark energy equation of state (w) holds a key to understanding the ultimate fate of the

A Tachyonic Scalar Field with Mutually Interacting Components

We investigate the tachyonic cosmological potential V(ϕ) in two different cases of the quasi-exponential expansion of universe and discuss various forms of interaction between the two



The universe at high-z, large-scale structure and the cosmic microwave background : proceedings of an Advanced Summer School, held at Laredo, Cantabria, Spain, 4-8 September 1995

Galaxy evolution from cluster and absorption-selected samples.- The Ly? clouds as tracers of the evolution of the universe.- High-redshift radio galaxies.- Spectral evolution of galaxies.- Galaxy

in Proceedings of an Advanced Summer Scho on the Universe at High-z

  • Large Scale Structure a the Cosmic Microwave Background, Laredo, Cantabri Spain, 1995,edited by E. Martinez-Gonzalez and J. Sanz (Springer-Verlag, Berlin, 1996); Wayne Hu, Naos Sugiyama, and Joseph Silk, Nature (London) 386, 37
  • 1997


  • J. 455, 7
  • 1995

For reviews of CMB anisotropy power spectrum physics and properties

  • Proceedings of the Snowmass Workshop on the Future of Particle Astrophysics and Cosmology
  • 1997

and references therein

  • and references therein
  • 1995

Proceedings of the Snowmass Workshop on the Future of Particle Astrophysics and Cosmology

  • Proceedings of the Snowmass Workshop on the Future of Particle Astrophysics and Cosmology
  • 1995

Ap. J

  • Ap. J
  • 1995

Turner and Martin White

  • Critical Dialogues in Cosmology


  • Nature
  • 1995