Which Weakens More Over Distance: Gravity or Light?

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Discussion Overview

The discussion centers on the comparative weakening of gravity and light as they propagate through space, exploring whether one weakens more than the other per unit of distance. Participants delve into theoretical implications, dimensional considerations, and the nature of forces in different spatial dimensions.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant suggests that gravity and light weaken at the same rate, proposing a model based on the spreading of energy over larger areas, akin to a "butter gun" analogy.
  • Another participant notes the coincidence of both gravity and light traveling at the speed of light and weakening proportionately to 1/r², hinting at a potential unification of the two phenomena.
  • Some participants discuss the implications of higher spatial dimensions, suggesting that if space were four-dimensional, forces might follow an inverse cube law instead of an inverse square law.
  • There are claims that gravity behaves poorly in dimensions beyond three, with references to instability in orbits as noted by Ehrenfest.
  • One participant raises the question of whether the inverse square law of gravity rules out the existence of a fourth spatial dimension, while another points out that the nuclear force may not adhere to the same law.
  • A later reply introduces the idea that discussions about higher dimensions may be irrelevant if atomic stability is compromised in those dimensions.

Areas of Agreement / Disagreement

Participants express a range of views on the weakening of gravity and light, with no consensus reached on whether one weakens more than the other. The discussion also includes competing ideas about the implications of higher dimensions and their effects on gravitational behavior.

Contextual Notes

Some claims depend on assumptions about dimensionality and the nature of forces, which remain unresolved. The discussion includes references to mathematical models and theoretical implications that are not fully explored.

sysreset
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Probably a really basic question but it bugs me:

Gravity weakens as it propogates through space. So does light and all electromagnetic signals. Does anyone have an opinion on which of the two weakens proportionately more per unit of distance, and why?
 
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There does not seem to me to be any reason to think that they do not "weaken" at the same rate. Basically, the "weakening" is a matter of the same amount being spread out over a larger spherical surface.

Back when I was in high school, my physics teacher had what he called a "butter gun". Basically it was a squirt gun with a pyramidal structure of rods attached. You put the toast between the rods and then squirted butter on it! The point was that, because area is proportional to the square of length, if you put the toast twice as far from the pistol, you could fit 4 pieces of toast where only one would fit before. Since you are firing the same amount of butter over 4 times the area, the thickness of butter is 1/4 as much on each slice of toast. Butter, light, or gravity, it's all 1/r2.
 
Odd that both gravity and light travel at c, and both wane proportionate to 1/r^2. Coincidence? I wonder what else gravity and light have in common. Makes me think that gravity and light are just two aspects of one unified phenomenon.
 
They occupy exponentially larger volumes of space as distance increases. The relative force falls off proportionately. Energy is always conserved.
 
if space were 4 dimensional then they would all follow an inverse cube law.
 
granpa said:
if space were 4 dimensional then they would all follow an inverse cube law.

Explain in laymans terms please?
 
in x dimensional space long range forces would be expected to follow a 1/(x-1) law
 
does that mean that since gravity etc. follows an invers squar law that the existence of a fourth spatial dimension can be ruled out?
 
it means that gravity is confined to our 3 dimensions.
 
  • #10
Gravity behaves poorly beyond 3 spatial dimensions.
 
  • #11
how so? poorly in what way?
 
  • #14
Of course if atoms are unstable in more than four dimensions, any discussion of higher order relationships is pointless. More than four dimensions are, however, apparently necessary [on local scales] to accommodate the zoo of exotic particles known to exist. This is a mathematical artifact, but, cannot be ignored.
 

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