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Variable Chaplygin Gas: Constraints from CMBR and SNe Ia

Geetanjali Sethi·Sushil K. Singh·Pranav Kumar·Deepak Jain·Abha Dev
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Abstract

We constrain the parameters of the variable Chaplygin gas model, using the location of peaks of the CMBR spectrum and SNe Ia ``gold '' data set. Equation of state of the model is $P=-A(a)/ρ$, where $A(a)=A_0 a^{-n}$ is a positive function of the cosmological scale factor $a$, $A_0$ and $n$ being constants. The variable Chaplygin gas interpolates from dust-dominated era to quintessence dominated era. The model is found to be compatible with current type Ia Supernovae data and location of first peak if the values of $Ω_m$ and $n$ lie in the interval $[0.017,~0.117]$ and $[-1.3,~2.6]$ respectively.

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Geetanjali Sethi, Sushil K. Singh, Pranav Kumar, Deepak Jain, Abha Dev. 2006-09-19. Variable Chaplygin Gas: Constraints from CMBR and SNe Ia. https://doi.org/10.1142/s0218271806008644

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