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| Content Provider | Springer Nature Link |
|---|---|
| Author | Asadzadeh, S. Safari, Z. Karami, K. Abdolmaleki, A. |
| Copyright Year | 2013 |
| Abstract | We study the polytropic gas scenario as the unification of dark matter and dark energy. We fit the model parameters by using the latest observational data including type Ia supernovae, baryon acoustic oscillation, cosmic microwave background, and Hubble parameter data. At 68.3 % and 95.4 % confidence levels, we find the best fit values of the model parameters as $\tilde{K}=0.742_{-0.024}^{+0.024}(1\sigma)_{-0.049}^{+0.048}(2\sigma)$ and $n=-1.05_{-0.08}^{+0.08}(1\sigma)_{-0.16}^{+0.15}(2\sigma)$ . Using the best fit values of the model, we obtain the evolutionary behaviors of the equation of state parameters of the polytropic gas model and dark energy, the deceleration parameter of the universe, the dimensionless density parameters of dark matter and dark energy as well as the growth factor of structure formation. Then, we investigate different energy conditions in the polytropic gas model and obtain that only the strong energy condition is violated for the special ranges of the redshift. We also conclude that in the this model, the universe starts from the matter dominated epoch and approaches a de Sitter phase at late times, as expected. Further, the universe begins to accelerate at redshift z $_{t}$=0.74. Furthermore, in contrary to the ΛCDM model, the cosmic coincidence problem is solved naturally in the polytropic gas scenario. Moreover, this model fits the data of the growth factor well as the ΛCDM model. |
| Starting Page | 1248 |
| Ending Page | 1262 |
| Page Count | 15 |
| File Format | |
| ISSN | 00207748 |
| Journal | International Journal of Theoretical Physics |
| Volume Number | 53 |
| Issue Number | 4 |
| e-ISSN | 15729575 |
| Language | English |
| Publisher | Springer US |
| Publisher Date | 2013-11-27 |
| Publisher Place | Boston |
| Access Restriction | One Nation One Subscription (ONOS) |
| Subject Keyword | Dark matter Dark energy Physics Quantum Physics Elementary Particles, Quantum Field Theory Theoretical, Mathematical and Computational Physics |
| Content Type | Text |
| Resource Type | Article |
| Subject | Physics and Astronomy Mathematics |
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