A Test of the Standard Cosmological Model with Geometry and Growth. (arXiv:2107.07538v2 [astro-ph.CO] UPDATED)

<a href="http://arxiv.org/find/astro-ph/1/au:+Andrade_U/0/1/0/all/0/1">Uendert Andrade</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Anbajagane_D/0/1/0/all/0/1">Dhayaa Anbajagane</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Marttens_R/0/1/0/all/0/1">Rodrigo von Marttens</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Huterer_D/0/1/0/all/0/1">Dragan Huterer</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Alcaniz_J/0/1/0/all/0/1">Jailson Alcaniz</a>

We perform a general test of the $Lambda{rm CDM}$ and $w {rm CDM}$

cosmological models by comparing constraints on the geometry of the expansion

history to those on the growth of structure. Specifically, we split the total

matter energy density, $Omega_M$, and (for $w {rm CDM}$) dark energy equation

of state, $w$, into two parameters each: one that captures the geometry, and

another that captures the growth. We constrain our split models using current

cosmological data, including type Ia supernovae, baryon acoustic oscillations,

redshift space distortions, gravitational lensing, and cosmic microwave

background (CMB) anisotropies. We focus on two tasks: (i) constraining

deviations from the standard model, captured by the parameters $DeltaOmega_M

equiv Omega_M^{rm grow}-Omega_M^{rm geom}$ and $Delta w equiv w^{rm

grow}-w^{rm geom}$, and (ii) investigating whether the $S_8$ tension between

the CMB and weak lensing can be translated into a tension between geometry and

growth, i.e. $DeltaOmega_M neq 0$, $Delta w neq 0$. In both the split

$Lambda{rm CDM}$ and $w {rm CDM}$ cases, our results from combining all data

are consistent with $DeltaOmega_M = 0$ and $Delta w = 0$. If we omit BAO/RSD

data and constrain the split $w {rm CDM}$ cosmology, we find the data prefers

$Delta w<0$ at $3.6sigma$ significance and $DeltaOmega_M>0$ at $4.2sigma$

evidence. We also find that for both CMB and weak lensing, $DeltaOmega_M$ and

$S_8$ are correlated, with CMB showing a slightly stronger correlation. The

general broadening of the contours in our extended model does alleviate the

$S_8$ tension, but the allowed nonzero values of $DeltaOmega_M$ do not

encompass the $S_8$ values that would point toward a mismatch between geometry

and growth as the origin of the tension.

We perform a general test of the $Lambda{rm CDM}$ and $w {rm CDM}$

cosmological models by comparing constraints on the geometry of the expansion

history to those on the growth of structure. Specifically, we split the total

matter energy density, $Omega_M$, and (for $w {rm CDM}$) dark energy equation

of state, $w$, into two parameters each: one that captures the geometry, and

another that captures the growth. We constrain our split models using current

cosmological data, including type Ia supernovae, baryon acoustic oscillations,

redshift space distortions, gravitational lensing, and cosmic microwave

background (CMB) anisotropies. We focus on two tasks: (i) constraining

deviations from the standard model, captured by the parameters $DeltaOmega_M

equiv Omega_M^{rm grow}-Omega_M^{rm geom}$ and $Delta w equiv w^{rm

grow}-w^{rm geom}$, and (ii) investigating whether the $S_8$ tension between

the CMB and weak lensing can be translated into a tension between geometry and

growth, i.e. $DeltaOmega_M neq 0$, $Delta w neq 0$. In both the split

$Lambda{rm CDM}$ and $w {rm CDM}$ cases, our results from combining all data

are consistent with $DeltaOmega_M = 0$ and $Delta w = 0$. If we omit BAO/RSD

data and constrain the split $w {rm CDM}$ cosmology, we find the data prefers

$Delta w<0$ at $3.6sigma$ significance and $DeltaOmega_M>0$ at $4.2sigma$

evidence. We also find that for both CMB and weak lensing, $DeltaOmega_M$ and

$S_8$ are correlated, with CMB showing a slightly stronger correlation. The

general broadening of the contours in our extended model does alleviate the

$S_8$ tension, but the allowed nonzero values of $DeltaOmega_M$ do not

encompass the $S_8$ values that would point toward a mismatch between geometry

and growth as the origin of the tension.

http://arxiv.org/icons/sfx.gif

Comments are closed, but trackbacks and pingbacks are open.