How The Expansion Rate Evolves: The Role Of Dark Energy, Textures, And Curvature

Details How The Expansion Rate Evolves: The Role Of Dark Energy, Textures, And Curvature How The Expansion Rate Evolves: The Role Of Dark Energy, Textures, And Curvature

May 2011

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011aas...21841004m&link_type=abstract

American Astronomical Society, AAS Meeting #218, #410.04; Bulletin of the American Astronomical Society, Vol. 43, 2011

Astronomy and Astrophysics

Astrophysics

Scientific paper

From a luminosity distance observer's viewpoint, the evolution of the square of the expansion rate H(z)/H0 can be fit by a polynomial expansion ΣΩna-n. Two of the first five coefficients, Ω3 and Ω4 are associated with matter and radiation. But the other three are physically more obscure: Ω0 is dark energy; Ω2 is called curvature; textures can be associated with Ω1. A strong constraint on the overall sum, ΣΩn, is that it is unity, observationally from the cosmic microwave background, and theoretically because the horizon problem demands inflation. Cosmic density observations suggest Ω3 0.27. However, supernova observations are agnostic as to the distribution of 1-Ω3 over Ω0, Ω1 and Ω2 provided Ω0 > 0.5 approximately. Baryonic Acoustic Oscillation observations at z 2 and the Dark Energy Survey will be more selective. In summary, one may introduce two additional parameters into the concordance cosmology, which are analytically, rather than physically, motivated. They can be measured via experiments outlined here. Observationally, textures and curvature may be ruled out, but only by future experiments.
We acknowledge support from ARC and the Centre for All-Sky Astrophysics (CAASTRO).

Affiliated with

Also associated with

No associations

Rating

How The Expansion Rate Evolves: The Role Of Dark Energy, Textures, And Curvature does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with How The Expansion Rate Evolves: The Role Of Dark Energy, Textures, And Curvature, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and How The Expansion Rate Evolves: The Role Of Dark Energy, Textures, And Curvature will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1743539