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Hubble’s Law

In the Face Book group:
My post:

Hubble's Law means a distant object moves at a recession velocity away from Earth  in direct relation (a linear constant) to its distance from the earth.

this is silly.
How is that 'rule' NOT treated as an observation error?

If the object moves closer to earth then as it approaches  that new location closer to earth its recession velocity is now slower relative to earth, with the velocity defined by this new distance to earth.

If the object moves farther from earth then as it approaches that new location farther from  earth its recession velocity is now faster relative to earth, with the velocity defined by this distance to earth.
To expect any distant object to have any behavior defined by its current distance from earth should be ridiculous.

Unfortunately the conversion from a redshift to a velocity uses an assumed expansion of the universe so I expect that is involved here.
Low redshifts do not conform to Hubble's Law; only large shifts are assumed to.

from Wikipedia:

'
For cosmological redshifts of z < 0.01 additional Doppler redshifts and blueshifts due to the peculiar motions of the galaxies relative to one another cause a wide scatter from the standard Hubble Law. The resulting situation can be illustrated by the Expanding Rubber Sheet Universe, a common cosmological analogy used to describe the expansion of space. If two objects are represented by ball bearings and spacetime by a stretching rubber sheet, the Doppler effect is caused by rolling the balls across the sheet to create peculiar motion. The cosmological redshift occurs when the ball bearings are stuck to the sheet and the sheet is stretched.

The redshifts of galaxies include both a component related to recessional velocity from expansion of the Universe, and a component related to peculiar motion (Doppler shift).The redshift due to expansion of the Universe depends upon the recessional velocity in a fashion determined by the cosmological model chosen to describe the expansion of the Universe, which is very different from how Doppler redshift depends upon local velocity. Describing the cosmological expansion origin of redshift, cosmologist Edward Robert Harrison said, "Light leaves a galaxy, which is stationary in its local region of space, and is eventually received by observers who are stationary in their own local region of space. Between the galaxy and the observer, light travels through vast regions of expanding space. As a result, all wavelengths of the light are stretched by the expansion of space.

Popular literature often uses the expression "Doppler redshift" instead of "cosmological redshift" to describe the redshift of galaxies dominated by the expansion of spacetime, but the cosmological redshift is not found using the relativistic Doppler equation which is instead characterized by special relativity; thus v > c is impossible while, in contrast, v > c is possible for cosmological redshifts because the space which separates the objects (for example, a quasar from the Earth) can expand faster than the speed of light. More mathematically, the viewpoint that "distant galaxies are receding" and the viewpoint that "the space between galaxies is expanding" are related by changing coordinate systems. Expressing this precisely requires working with the mathematics of the Friedmann-Robertson-Walker metric.
'

I note:

'
The redshift due to expansion of the Universe depends upon the recessional velocity in a fashion determined by the cosmological model chosen to describe the expansion of the Universe, which is very different from how Doppler redshift depends upon local velocity.'

Translation:
We assume the universe behaves according to our model.

I note:

'
the viewpoint that "distant galaxies are receding" and the viewpoint that "the space between galaxies is expanding" are related by changing coordinate systems.

Translation:

The view  of the expansion of the universe is part of the observer's frame of reference and changing its coordinate system.

I note:

'
thus v > c is impossible while, in contrast, v > c is possible for cosmological redshifts because the space which separates the objects (for example, a quasar from the Earth) can expand faster than the speed of light.
'
Translation:

This concept of an expanding universe is required to solve the problem of: v > c.

Conclusion:

If cosmologists would ever consider a large red shift can have an intrinsic component so the non intrinsic part of v is not > c, proposed many years ago based on analysis of large red shift objects in proximity to low red shift objects then there would be no need to require the space in the observer's frame of reference is expanding in all directions away from Earth at a rate predicted by our model.


link
https://en.wikipedia.org/wiki/Hubble%27s_law

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