I Calculating recession vs attraction

[richardSPM]

How does one calculate the distance from a galaxy or galaxy cluster where recession due to dark energy begins and "attraction" ends?

 

[mathman]

https://www.sciencemeetsreligion.org/physics/distance.php

The above may help. Dark energy does not play a role in this description. Dark energy is inferred when Doppler shift distance measurement is compared with that described in the reference - particularly using supernovae type 1a.

 

[richardSPM]

Thank you for your prompt reply. I do understand the idea behind using supernovae type 1a as a standard candle to calculate distance and red shift to calculate the recession rate. What I am trying to ask is, If you have an object, galaxy or galaxy cluster, of known mass how does one calculate the distance from said galaxy where it no longer has an effect on the curvature of space-time? (ie there is no longer an attractive force) I assume it would be at this distance that expansion would begin to cause recession.

 

[Drakkith]

Are you looking for the actual equations used to calculate things? Or just a layman's description?

 

[richardSPM]

I'll take either.

 

[Jorrie]

If you have an object, galaxy or galaxy cluster, of known mass how does one calculate the distance from said galaxy where it no longer has an effect on the curvature of space-time? (ie there is no longer an attractive force) I assume it would be at this distance that expansion would begin to cause recession.

A good technical discussion can be found in: On the influence of the global cosmological expansion on the local dynamics in the Solar System, Carrera et al. They do extend it to larger scales as well.

For what it's worth, I once used it to calculate the radius from the center of an isolated, spherical mass, where the accelerated expansion would cause a non-orbiting (stationary relative to the mass) particle to drift off and not fall into the cluster. This depends essentially just on the mass, Ho and the cosmological constant (lambda). In such a hypothetical (isolated) case, a free particle will always fall in if there is no lambda. If you are interested, also look at the Tethered Galaxy scenario, Davis et. al.

 

[richardSPM]

Hi Jorrie,
Thanks for responding. According to the SPM, recession would begin at a distance equal to the radius of a sphere that had a density equal to the critical density with the object at its center. Is this not a currently accepted premise based on LCDM?

 

[Jorrie]

According to the SPM, recession would begin at a distance equal to the radius of a sphere that had a density equal to the critical density with the object at its center. Is this not a currently accepted premise based on LCDM?

Hi Richard, if I remembered correctly, SPM is a personal theory of yours that we did discuss on another forum. If I'm correct, then discussion of SPM is not allowed on this forum, which is reserved for mainstream theory and papers published in scientifically reputable media. I trust that you have read the general forum guidelines?

The short answer to your question is: no, the LCDM model, coupled to present observations, do not support such a model or premise.

 

[PeterDonis]

According to the SPM

if I remembered correctly, SPM is a personal theory of yours

And if that is the case, then @Jorrie is correct that it's out of bounds for discussion here.

In any case, the substantive question posed in the OP appears to have been answered, so either way this thread can be closed. @richardSPM , please review the PF guidelines as @Jorrie suggested. If you want to discuss SPM here, you will need to provide valid references (published peer-reviewed papers) as a basis for discussion.