https://doi.org/10.1140/epjc/s10052-009-0876-7
Regular Article - Theoretical Physics
Features of holographic dark energy under combined cosmological constraints
1
Kavli Institute for Theoretical Physics China, Institute of Theoretical Physics, Chinese Academy of Sciences, P.O. Box 2735, Beijing, 100080, China
2
Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA, UK
3
National Astronomical Observatories, Chinese Academy of Sciences, Beijing, 100012, China
* e-mail: yzm20@cam.ac.uk
Received:
25
October
2008
Revised:
15
December
2008
Published online:
12
February
2009
We investigate the observational signatures of the holographic dark-energy models, including both the original model and a model with an interaction term between the dark energy and dark matter. We first delineate the dynamical behavior of such models, especially considering whether they would have a “big rip” for different parameters; then we use several recent observations, including 182 high-quality type Ia supernovae data observed with the Hubble Space Telescope, the SNLS and ESSENCE surveys, 42 latest Chandra X-ray cluster gas mass fraction, 27 high-redshift gamma-ray burst samples, the baryon acoustic oscillation measurement from the Sloan Digital Sky Survey, and the CMB shift parameter from the WMAP three-year result to give more reliable and tighter constraints on the holographic dark-energy models. The results of our constraints for the holographic dark-energy model without interaction is c=0.748 −0.009 +0.108 , Ω m0=0.276 −0.016 +0.017 , and for the model with interaction (c=0.692 −0.107 +0.135 , Ω m0=0.281 −0.017 +0.017 , α=−0.006 −0.024 +0.021 , where α is an interacting parameter). As these models have more parameters than the ΛCDM model, we use the Bayesian Evidence as a model-selection criterion to make comparisons. We found that the holographic dark-energy models are mildly favored by the observations as compared to the ΛCDM model.
© Springer-Verlag , 2009
