Constraints on the sound speed of dark energy

doi:10.1103/PhysRevD.71.103519

Paper

Constraints on the sound speed of dark energy

Published Apr 1, 2005 · S. Hannestad

Physical Review D

90

Citations

3

Influential Citations

Full textSemantic Scholar

Abstract

We have studied constraints on the equation of state, w, and speed of sound, c{sub s}, of the dark energy from a joint analysis of data from the cosmic microwave background, large scale structure and type-Ia supernovae. We find that current observations have no significant sensitivity to c{sub s}. However, there is a slight difference between models in which there are no dark energy perturbations and models in which dark energy behaves as a fluid. Assuming that there are no dark energy perturbations shifts the allowed region for w to slightly higher values. At present models with and without dark energy perturbations provide roughly equally good fits to observations, but the difference is potentially important for future parameter estimations. Finally, we have also performed error forecasts for future measurements of c{sub s}.

Highly Cited

Study Snapshot

Current observations have no significant sensitivity to the sound speed of dark energy, but models with and without dark energy perturbations provide roughly equal good fits to observations, potentially impacting future parameter estimations.

PopulationOlder adults (50-71 years)

Sample size24

MethodsObservational

OutcomesBody Mass Index projections

ResultsSocial networks mitigate obesity in older groups.

Constraints on the sound speed of dark energy

References

Citations