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Title: Statefinder diagnostic for the modified polytropic Cardassian universe

Abstract

We apply the statefinder diagnostic to the modified polytropic Cardassian universe in this work. We find that the statefinder diagnostic is quite effective to distinguish Cardassian models from a series of other cosmological models. The s-r plane is used to classify the modified polytropic Cardassian models into six cases. The evolutionary trajectories in the s-r plane for the cases with different n and {beta} reveal different evolutionary properties of the universe. In addition, we combine the observational H(z) data, the cosmic microwave background data, and the baryonic acoustic oscillation data to make a joint analysis. We find that case 2 can be excluded at the 68.3% confidence level and any case is consistent with the observations at the 95.4% confidence level.

Authors:
;  [1]
  1. Department of Astronomy, Beijing Normal University, Beijing, 100875 (China)
Publication Date:
OSTI Identifier:
21020357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 8; Other Information: DOI: 10.1103/PhysRevD.75.083515; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; BARYONS; COSMOLOGICAL MODELS; COSMOLOGY; OSCILLATIONS; RELICT RADIATION; UNIVERSE

Citation Formats

Yi Zelong, and Zhang Tongjie. Statefinder diagnostic for the modified polytropic Cardassian universe. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.083515.
Yi Zelong, & Zhang Tongjie. Statefinder diagnostic for the modified polytropic Cardassian universe. United States. doi:10.1103/PHYSREVD.75.083515.
Yi Zelong, and Zhang Tongjie. Sun . "Statefinder diagnostic for the modified polytropic Cardassian universe". United States. doi:10.1103/PHYSREVD.75.083515.
@article{osti_21020357,
title = {Statefinder diagnostic for the modified polytropic Cardassian universe},
author = {Yi Zelong and Zhang Tongjie},
abstractNote = {We apply the statefinder diagnostic to the modified polytropic Cardassian universe in this work. We find that the statefinder diagnostic is quite effective to distinguish Cardassian models from a series of other cosmological models. The s-r plane is used to classify the modified polytropic Cardassian models into six cases. The evolutionary trajectories in the s-r plane for the cases with different n and {beta} reveal different evolutionary properties of the universe. In addition, we combine the observational H(z) data, the cosmic microwave background data, and the baryonic acoustic oscillation data to make a joint analysis. We find that case 2 can be excluded at the 68.3% confidence level and any case is consistent with the observations at the 95.4% confidence level.},
doi = {10.1103/PHYSREVD.75.083515},
journal = {Physical Review. D, Particles Fields},
number = 8,
volume = 75,
place = {United States},
year = {Sun Apr 15 00:00:00 EDT 2007},
month = {Sun Apr 15 00:00:00 EDT 2007}
}
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