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Participant |
Banijamali, Ali | |||||||
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Institution |
Babol Noshirvani University of Technology - Shariati - Babol - Mazandaran - Iran | |||||||
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Session |
DE1 |
Accepted |
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Order |
Time |
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Talk |
Poster abstract |
Title |
Chameleon Dark Energy: Dynamical Analysis and Cosmological Constraints | |||||
| Coauthors | Bellucci, Stefano; Fazlpour, Behnaz; Solbi, Milad | |||||||
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Abstract |
In this work we first study the phase space of tachyonic chameleon dark energy for four different combinations of the tachyonic potential $V(\phi)$ and the coupling function $f(\phi)$ between the chameleon field and the matter. We find some stable solution in which accelerated expansion of the universe is satisfied. Among them, a scaling attractor was found that can give rise to the late-time acceleration of the universe and alleviate the coincidence problem. Then, we use data from Type Ia supernova (SN Ia) and Baryon Acoustic Oscillations to place constraints on the model parameters and show that the scenario is compatible with observations. |
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Pdf file |
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Session |
AT7 |
Accepted |
Yes |
Order |
5 |
Time |
16:35 | 15' + 5' |
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Talk |
Oral abstract |
Title |
Dynamics And Observational Constraints On A Scalar-tensor Model With Gauss-Bonnet Coupling | |||||
| Coauthors | Bellucci, Stefano; Fazlpour, Behnaz; Solbi, Milad | |||||||
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Abstract |
In the current work we study the dynamics of a scalar-tensor model of dark energy in which scalar field that plays the role of dark energy, non-minimally coupled to the Gauss-Bonnet invariant in 4 dimensions. We utilize the dynamical system method to extract the critical points of the model. We find scaling attractor solutions with the property that the ratio of dark energy and dark matter density parameters are of order one. These solutions give the hope to alleviate the well-know coincidence problem in cosmology. We also obtain constraints on the free parameters by using different sources of cosmological data. The viability of the model is explored by combining the conditions imposed by the Type Ia supernova (SN Ia) and Baryon Acoustic Oscillations data. |
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Pdf file |
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