Gravity at very large distance

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In summary, the conversation discusses whether gravity is zero at very large distances and the concept of quantized energy. It also touches on the idea of using photons instead of electrons to study gravity and how gravity is affected by space-time deformations. The conclusion is that gravity has a universal effect, with larger bodies having a greater influence on the universe's expansion.
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Is gravity at very large distances zero?

ie g = (k(m1 m2)/r^2) - k1 (you can also use the relativity formule for gravity here if you want)where k1 is some constant that makes gravity zero when (k(m1 m2)/r^2) reaches some threshold value

so if I had and electron 10^6 billion light years from another electron (ie the opposite ends of the universe or the furtherest distance possible (you choose)).

Now let's assume electron 1 is doing work, through gravity, on electron 2. I was wondering would the energy associated with the work electron 1 does on electron 2 be smaller than the smallest indivisibe unit of energy, which I think is planks constant?. Of course this assumes energy is quantised.

If you assume 2 photons can have a gravitational effect on each other then you can replace electron 1 and 2 with photon 1 and 2 at opposite ends of the universe.
 
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  • #2
Using the inverse square law on 2 electrons 13.5 billion light years apart you get a force of 3.4x10-123N. I guess this would make the question pointless because by trying to measure the force QM laws would change your results any way. There isn't much point thinking about gravity in that way.
 
  • #3
Those electrons would be via entangled, and gravity is universal.
 
  • #4
Gravity depends of space-time deformation. If you have large size bodies having reasonnable mass, they will deform space - time on large distances but deformations will be low. For atomic particles, deformations are extremely important but they act on short distances. Consequently, interactions between atomic particles only exist at small scales and interactions btween planets and stars exist on large scales. For black holes, you are in the case of strong deformations with large bodies. Then their influence govern universe expansion... and it accelerate ! interesting isn't it ?
 

1. How does gravity behave at very large distances?

The force of gravity decreases as distance increases. This is known as the inverse square law, which states that the strength of gravity is inversely proportional to the square of the distance between two objects. This means that the further apart two objects are, the weaker the force of gravity between them.

2. Can gravity travel through empty space?

Yes, gravity can travel through empty space. This is because gravity is a fundamental force that does not require a medium to travel through. It can act over vast distances, even in the vacuum of space.

3. What is the role of gravity in the formation of galaxies?

Gravity plays a crucial role in the formation of galaxies. As particles in the early universe clumped together due to gravity, they formed larger and larger structures, eventually leading to the formation of galaxies. Gravity also holds galaxies together and governs the motion of stars and other celestial bodies within them.

4. How does the force of gravity change with the mass of an object?

The force of gravity is directly proportional to the mass of an object. This means that the greater the mass of an object, the stronger its gravitational pull. For example, the force of gravity between the Earth and the Moon is much stronger than the force between the Earth and a smaller object, such as a pebble.

5. Is there a limit to the distance at which gravity can act?

According to the theory of general relativity, there is no limit to the distance at which gravity can act. However, the strength of gravity decreases significantly as distance increases, so its effects may become imperceptible at extremely large distances. Additionally, the expansion of the universe may also play a role in limiting the reach of gravity over vast distances.

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