You are here:



I don't have any background in physics so please excuse me if I'm missing something that is common knowledge. That being said, Is it possible that gravity is a finite force in the universe? Thinking of gravity as the force exerted on spacetime by an object with mass, in an expanding universe where the universe is continually being ‘stretched’ is it possible that gravity becomes weaker as time goes on? A weak analogy would be if you put an object on a piece of cloth that had some slack, you would see the force the object exerts on the sheet by how much it makes the sheet depress. Now when you raise the tension on the sheet, the force the object exerts stays the same but since the sheet has its own force, the object leaves less of an impact. Now obviously this would only apply if the universe were ‘stretching’ and not ‘growing’ and I’m not sure which is the case. In relation to how this would make gravity finite is that if it were that case that the universe were stretching, would it be possible for the tension or force that spacetime has on an object to reach a degree where objects of mass would leave an unnoticeable impression on spacetime and therefore making gravity and even weaker force locally. Now that wouldn’t make gravity nonexistent but rather its total force would be spread out over such a large distance (the entire universe) that it would be negligible. For the purposes of this I’m assuming that gravity isn’t influenced by a particle. Again please pardon my lack of expertise in the subject, but I’m curious to know whether or not my understanding of gravity is correct.
P.S. I attached a photo to try and show you my thinking, maybe I'm following the picture too literally.

This is really a big, unanswered question in physics, about the behavior of gravitation over long times/distances.  It's really hard to answer it the way you asked it, especially at the end when you said you were assuming it wasn't influenced by a particle.  Particles have mass, mass affects gravitation, and the Higgs boson has recently been confirmed to exist.  Therefore particles do affect gravitation.  Do you have a more specific question?  Are you trying to verify or reject MOND?  (MOdified Newtonian Dynamics)


All Answers

Answers by Expert:

Ask Experts


Dr. Stephen O. Nelson


Fusion, solar flares, cosmic rays, radiation in space, and stellar physics questions. Generally, nuclear-related astrophysics, but I can usually point you in the right direction if it's not nuclear-related or if it's nuclear but not astrophysics.


Just moved from being a physics professor at the University of Texas of the Permian Basin into government work. Doctoral dissertation was on a reaction in CNO-cycle fusion, worked in gamma-ray astronomy in the space science division of the naval research laboratory in the high-energy space environment branch.

Government work as a physical scientist with a nuclear focus.

Ph.D. in physics, research was on nuclear fusion reactions important in stellar fusion, further work on space telescope technology.

©2017 All rights reserved.