It's known that the current value of the universe's total density parameter $\Omega_0=1$.

According to the $\Lambda$CDM model, the current density parameter of baryonic matter $\Omega_P \sim 0.04$, the current density parameter of dark matter $\Omega_D \sim 0.25$, and the current density parameter of dark energy $\Omega_\Lambda \sim 0.7$. While the energy density of radiation is ignored.

Suppose another model like in : A unified geometric description of the Universe

Where $\Omega_\Lambda$ is taken to be zero. And the density parameter of both baryonic and dark matters is taken to be $0.99$.

Although this model explained the late-time acceleration. Will it meet the observation of $\Lambda$CDM about dark matter or baryonic matter?

I mean the universe introduced in the model is matter dominant with say huge density parameter of dark matter $\sim 0.95$ and density parameter of baryonic matter $\sim 0.04$ . Will this be consistent with the early cosmological observations like the Baryonic acoustic oscillation in the early universe (BAO) or the microwave background (CMB) ?

Any help is appreciated!

  • $\begingroup$ The paper you link to involves a theory of modified gravity (not general relativity, aka GR). Is your question: "are there theories of modified gravity where $\Omega_{\Lambda}=0$", or is your question "within GR and 'standard cosmology', is it acceptable to set $\Omega_{\Lambda}=0$"? $\endgroup$
    – Andrew
    Dec 29, 2022 at 12:40
  • $\begingroup$ My question about $\Omega_{P}$ and $\Omega_{D}$ in the GILA model which has been studied in the paper. In this model, if $\Omega$ for both baryonic and dark matters is around ~ 0.99, that means they may assume $\Omega_{D} \sim 0.95$. Won't that huge amount of dark matter has any effects/contradictions on the early cosmic observations like BAO or CMB? $\endgroup$
    – Dr. phy
    Dec 29, 2022 at 14:17
  • $\begingroup$ Of course, it would have some effects. Changing the dark matter density changes the CMB redshift and also some other cosmological parameters and matter perturbations. $\endgroup$
    – seVenVo1d
    Jan 1 at 2:08


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