Is vacuum acceleration directly proportional to distance?

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Discussion Overview

The discussion revolves around the relationship between vacuum acceleration and distance, specifically whether this acceleration is directly proportional to distance or follows a different mathematical relationship. The inquiry seeks to explore theoretical models and observational data, excluding gravitational effects.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • One participant questions if the instantaneous or observed acceleration due to vacuum is directly proportional to distance, proposing various mathematical forms such as A~D, A~D^2, A~D^(1/2), A~D^(-2), and A = constant.
  • Another participant seeks clarification on what is meant by "instantaneous/observed acceleration due to the vacuum," specifically referencing the observed acceleration of distant objects from supernova data.
  • A later reply suggests that distances are growing according to a function resembling exponential growth, indicating that the acceleration may be proportional to distance multiplied by a constant related to this growth.
  • The mention of the Hypersine thread is noted as a source for understanding the acceleration rate, with references to specific mathematical expressions and graphs illustrating distance growth.

Areas of Agreement / Disagreement

Participants express uncertainty regarding the relationship between vacuum acceleration and distance, with multiple competing views on the mathematical models that may describe this relationship. The discussion remains unresolved.

Contextual Notes

Limitations include the lack of precise data to definitively establish the relationship between vacuum acceleration and distance, as well as the dependence on specific definitions and assumptions regarding acceleration in a vacuum.

69911e
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Do we know if the instantaneous/observed acceleration due to the vacuum is directly proportional to distance or possibly? (ignore any gravitational effects)
A~D ?
A~D^2 ?
A~D^(1/2) ?
A~D^(-2)
A~D^(Other) ?
OR
A= constant (edited as I forgot this one)

If not, is there a best guess/fit or simply not precise enough data?

Feel free to correct my question if it is simply a bad question. I didn't see this directly address in any thread; if I missed one, a link would be great.
 
Last edited:
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69911e said:
the instantaneous/observed acceleration due to the vacuum

What do you mean by this?
 
PeterDonis said:
What do you mean by this?

The observed acceleration of distant objects from the supernova data or other observation.
 
69911e said:
Do we know if the instantaneous/observed acceleration due to the vacuum is directly proportional to distance or possibly? ... if I missed one, a link would be great.

You could look at the Hypersine thread.

To an excellent approximation, distances are growing and are expected to continue growing as the function
sinh2/3(1.5 t) where the present is at time t = 0.8

This looks more and more like exponential growth (at a very low rate of about 1/173 % per million years) as time goes on. Eventually it will be indistinguishable from exponential growth at that rate call it H

D(t) = eHt

If you differentiate that you get the expansion speed is proportional to the distance multiplied by H and if you take the derivative again you get the acceleration is proportional to the distance multiplied by the square of H

The Hypersine thread https://www.physicsforums.com/threads/the-hypersine-cosmic-model.819954/#post-5146660
has some graphs that show the distance growth curve and the gradual onset of exponential growth at a small constant rate.
 
Last edited:
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The Hypersine thread provided the understanding of the acceleration rate I was looking for.
Thanks!
 

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