New Variable Modified Chaplygin Gas Research Articles

Gravitational lensing: dark energy models in non-flat FRW Universe

In a non-flat FRW model, we have considered our Universe to be filled with non-interacting dark energy and dark matter. For the dark energy models, we have assumed Tachyonic Field (TF), Generalized Cosmic Chaplygin Gas (GCCG), New Variable Modified Chaplygin Gas (NVMCG), Modified Chaplygin–Jacobi Gas (MCJG), and Modified Chaplygin–Abel Gas (MCAG). We then analyzed these dark energy models with varying cosmological parameters in their optical depth behaviour and presented our result graphically. Later on, a comparison of our findings of the corresponding models in flat and non-flat Universe with the Lambda CDM model has also been presented.

Constraining the Parameters of New Variable Modified Chaplygin Gas Model

Assuming the flat FRW universe in Einstein’s gravity filled with New Variable Modified Chaplygin gas (NVMCG) dark energy and dark matter having negligible pressure. In this research work we analyze the viability on the basis of recent observation. Hubble parameter H is expressed in terms of the observable parameters H 0, $\varOmega_{m}^{0}$ and the model parameters A 0, B 0, C 0, m, n, α and the red shift parameter z. Here we find a best fitted parameter range of A 0, B 0 keeping 0≤α≤1 and using Stern data set (12 points) by minimizing the χ 2 test at 66 %, 90 % and 99 % confidence levels. Next we do the joint analysis with BAO and CMB observations. Again evaluating the distance modulus μ(z) vs redshift (z) curve obtained in the model NVMCG with dark matter with the best fitted value of the parameters and comparing with that derived from the Union2 compilation data.

Correspondence of F-essence with Chaplygin gas cosmology

In this work, we have considered generalized cosmic Chaplygin gas (GCCG) and new variable modified Chaplygin gas (NVMCG) types of dark energies in the framework of F -essence cosmology and investigated the consequences for their co-existence. The correspondence of the F -essence with the above types of Chaplygin gas models has been investigated. The natures of K and Y for this correspondence of the F -essence with all the gases have been analyzed graphically. From the graphical representation, we demand that K always increases with Y due to correspondence, and the EoS parameter w shows that the F -essence model always gives only quintessence type of dark energy and phantom crossing does not happen in our constructed models.

Accretion of new variable modified Chaplygin gas and generalized cosmic Chaplygin gas onto Schwarzschild and Kerr–Newman black holes

In this work, we have studied accretion of the dark energies in new variable modified Chaplygin gas (NVMCG) and generalized cosmic Chaplygin gas (GCCG) models onto Schwarzschild and Kerr–Newman black holes. We find the expression of the critical four velocity component which gradually decreases for the fluid flow towards the Schwarzschild as well as the Kerr–Newman black hole. We also find the expression for the change of mass of the black hole in both cases. For the Kerr–Newman black hole, which is rotating and charged, we calculate the specific angular momentum and total angular momentum. We showed that in both cases, due to accretion of dark energy, the mass of the black hole increases and angular momentum increases in the case of a Kerr–Newman black hole.