Need help with density parameters of the LambdaCDM model

[stephaneww]

\textif I understand correctly (because I didn't understand everything) for z=0.791, doing [latex]\Omega_b=M_b/M_{total}[/latex] is not a good approximation ?

well,  I redid the table with the same values but with 100 steps

The difference [latex]\Omega_b / \Omega_m[/latex] for z=0 et z=0.124 becomes minor : 0.05%

Can we say that [latex] M_b_\text{(t-1)}/ M_b_text{(t)}[/latex] from close to close ?

Edited February 17, 2019 by stephaneww

[stephaneww]

 

1 hour ago, stephaneww said:

 

well,  I redid the table with the same values but with 100 steps

The difference Ωb/Ωm for z=0 and z=0.124 becomes minor : 0.05%

merge then edit too late :

Can we say that [latex]M_\text{b(t-1)} =  M_\text{b(t)}[/latex] from close to close ?

Edited February 17, 2019 by stephaneww

[Mordred]

In a short enough time frame one can safely assume the Baryon density will remain roughly the same or that the [latex] (1-z)^4[/latex] will provide a sufficient approximation. However that boils down to a choice of the accuracy one wants....one can for example make some reasonable assumptions that the chemical processes by and large are not undergoing a phase transition in our current universe. This simplifies a great deal as one must simply account for the expansion vs density relations under reasonable approximation

Edited February 17, 2019 by Mordred

[stephaneww]

Thank you for everything, Mordred.

If we assume, for example, that [latex]M_b * \Lambda= cst[/latex] then, when [latex]M_b[/latex] decreases [latex] \Lambda[/latex] increases inversely proportional.

Could this be a part of the explanation for the fact that it seems that the acceleration of expansion is also accelerated?

Edited February 18, 2019 by stephaneww