Universal Gravity: Does It Affect Us Beyond the CEH Line?

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Discussion Overview

The discussion revolves around the effects of universal gravity in relation to the Cosmic Event Horizon (CEH) and whether gravitational influences from galaxies beyond this line affect Earth. It explores theoretical implications of gravity and electromagnetic waves, as well as observational phenomena related to galaxies near the CEH.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant questions whether gravity from galaxies beyond the CEH still affects Earth, given that electromagnetic waves cannot reach us from those regions.
  • Another participant argues that while we cannot send signals to galaxies beyond the CEH today, past signals may still reach them, and vice versa, suggesting that gravitational effects propagate similarly to electromagnetic signals.
  • A participant notes that the gravitational influence of our mass and motion continues to propagate outward, implying that we still exert gravitational effects on galaxies that are now beyond the CEH.
  • One participant highlights the phenomenon of observing galaxies that have crossed the CEH, noting that their images appear to slow down and redshift as they approach the horizon, akin to objects falling into a black hole.

Areas of Agreement / Disagreement

Participants express differing views on the nature of gravitational effects from galaxies beyond the CEH, with some suggesting that these effects persist while others question the implications of such influences. The discussion remains unresolved regarding the extent and nature of these gravitational interactions.

Contextual Notes

The discussion involves assumptions about the propagation of gravitational effects and the nature of signals across cosmic distances, which may not be fully explored or defined.

Gaz
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Well we have been talking about the size of the universe and em waves all day and it's lead me to ask this.

EM waves can no longer effect us from passed the CEH line right . And if gravity also travels at the speed of light a does this mean that once these galaxies are gone passed the CEH they no longer have any gravitational effect on Earth?
 
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Galaxies beyond CEH are ones we cannot send a signal to today, and have it eventually reach them. But signals we sent out in the past might still reach them.

Likewise signals THEY already sent out in the past might eventually reach us and affect us.

That goes both for EM and for gravity.

BTW you know that two neutron stars in tight orbit around each other are sending out ripples in the geometry (according to GR).
So when you think of sending a signal it could be pushing some electrons up and down along an antenna, or it could be waving a neutron star around and sending ripples in the geometry.

There is no "action at a distance". What we have done in the past affected the geometry around us, and that effect propagates outward and continues to do so.

So our gravity would continue to be FELT by a galaxy that is now outside CEH range. But it would not be the geometric effect of what we do today. It would be the geometric effect of our mass and motion as it was in the past---that has propagated out and eventually reached them.
 
It is interesting that we never stop seeing galaxies that have passed out of CEH range, their images just pile up at the horizon and slowly redshift into undetectability.

We never actually see them pass thru the horizon. We see them in slow motion as they were right before---with time slowing down more and more.

It is like how we see stuff that has fallen thru the event horizon of a BH. We don't see the stuff pass thru and suddenly wink out. It has passed thru but we see it as it was just about to pass thru, but with its time slowed down more and more. piling up like dead leaves on the horizon and redshifting into undetectability
 
That is pretty cool(the neutron star). And I see what you mean thanks =)
 

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