Gamma in Brans-Dicke framework

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Apashanka
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I take an empirical relation of Φ=Φ0(a/a0)n where n=-(dG/dt)/GH ,present study shows n is negative ,implies that G increases with time
And using this fact and taking a scale factor of the form sinh(t) ,evaluated ϒ and then plot it with respect to t and got the above figure which is consistent with many other work done.
Present study shows ϒ(n,t0)=-0.67 to -1.67
n is chosen in such a way in the above plot.
From the plot it is concluded the transition time of positive pressure to negative pressure and start up time of the accelerated expansion.
But if we consider our universe to be dominated by radiation at very early epoch followed by matter then ϒ decreases from 1/3 to 0 and then -ve but this study and many other study shows ϒ increases first and then transit to -ve value as shown in the plot??
Is there is something which I am missing
 

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PeterDonis said:
Where is all this coming from? What "study" are you talking about? What are ##\Phi## and ##\Upsilon##?
Φ is the scaler field of Brans-Dicke theory and ϒ is of pressure relation P=ϒρ ,ρ is the energy -density
 
Dale said:
Please cite the study also
Page 4731
 

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Research India Publications is a known predatory publisher. I would be highly skeptical of anything found only in one of their journals.

Current evidence places the ##\omega## parameter at somewhere greater than 40000. The paper talks about ##\omega## on the order of unity, so I get the impression that the author may be unaware of the evidence. This could be a likely reason that the paper wound up in a predatory journal. I would not spend too much time on it.
 
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