Is This Equation Accurate for Determining the Size of the Universe?

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Discussion Overview

The discussion centers around the validity of a proposed equation for determining the size of the universe, specifically examining its components and implications. Participants explore theoretical aspects, definitions of symbols, and the relationship between the equation and the observable universe.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant presents the equation ##c^2/r^2=πGp_Λ## and asks for its correctness, suggesting that ##r## represents a spherical volume radius that is significantly larger than inter-galaxy distances but smaller than the universe's size.
  • Another participant requests clarification on the symbols used in the equation and the context from which it originates, questioning the radius being referenced.
  • A participant suggests that ##r## could represent the radius of the observable universe.
  • There is a query about the meaning of ##p_\Lambda##, which is identified by another participant as dark energy density.
  • A participant questions the logical and numerical accuracy of the equation, seeking validation of its units and implications.
  • One participant argues that the equation yields a value of 26 billion light years, which does not correspond to the radius of the observable universe, and expresses skepticism about the equation's relevance, suggesting it may be a personal theory that does not contribute meaningfully to the discussion.
  • It is noted that while the units of the equation match, this alignment does not necessarily imply correctness, as ##G p_\Lambda## is related to the Hubble time in the distant future.

Areas of Agreement / Disagreement

Participants express differing views on the validity and implications of the proposed equation, with some questioning its relevance and others seeking clarification on its components. No consensus is reached regarding the equation's accuracy or its significance in determining the size of the universe.

Contextual Notes

Participants highlight the need for clarity on the definitions of symbols and the context of the equation, indicating potential limitations in understanding its application and relevance.

RyanH42
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##c^2/r^2=πGp_Λ## I want you to check this equation.Is that correct ?

And ##r=r_0a(t)##.Here ##r## is a spherical volume of radius , where is much larger than the average inter-galaxy
distance, and much smaller than the size of the universe.

If r has a value here then , Is that value equal some sorth of important thing ?

Thank you
 
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What do the symbols mean, and where does the equation come from? (I can guess what c, ##\pi## and G are...)
Radius of what?
 
Radius of observable universe or you can suppose close to that number.
 
What's p lambda?
 
Dark energy density
 
Is my equation true in units,numbers and of course logically ?
 
The equation gives 26 billion light years, which is not the radius of the observable universe. Also, there is no reason to expect that the right side (which is probably time-independent) matches the left side (which is not) exactly today.
This looks like a personal theory - we do not allow the discussion of those, that leads to nothing useful.

The units match but that is not surprising. ##G p_\Lambda## will be related to the Hubble time in the distant future.
 

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