Recently scientist have proved that gravitational waves travel through spacetime fabric and any mass object distorts the space fabric because of which we fill gravitational pull. My question is if the theory of gravity because of distorted spacetime fabric is correct what is the axis of mass object and why do we feel gravity all around the earth whether we are on north pole or south pole? I think as the theory is correct gravity must work only in downwards direction towards the distorted spacetime fabric centre not all around the mass object?

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    $\begingroup$ I wonder if you are thinking of the rubber sheet analogy. If so you need to bear in mind that this is only a 2D representation of the curvature, and spacetime is actually a 4D curved stucture. $\endgroup$ Sep 20 '17 at 19:19

As John Rennie said, I think you might be thinking of the rubber sheet analogy:

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In which case your question makes a lot of sense. So here I must curse it and ban you from ever thinking of it again. A better mental picture to have might be

enter image description here

This is a significantly better image, and it already addresses your questions. Gravity does work all around the object; the rubber sheet analogy just doesn't show it. Now, in this newer model, we can see that spacetime is 3-d, and Earth pulls it in around its entire self, instead of making a dent in a sheet.

However, again, we must be careful. This model doesn't explain how time is affected by gravity. In the end, we must take the words of xkcd to heart:

enter image description here

Any analogy like this is imperfect. In the end, understanding Einstein's field equations and their consequences is the best way to figure out what's going on.

  • $\begingroup$ Thank you so much Heather for clarifying my thoughts with your really helpful explanation. I was actually thinking of space fabric as a rubber sheet due to which I got this confusion in my mind $\endgroup$ Sep 22 '17 at 0:53
  • $\begingroup$ Well I still have a doubt. In your answer you have written "we can see that spacetime is 3-d, and Earth pulls it in around its entire self, instead of making a dent in a sheet." Can you please explain what (which force) causes the earth to pull the space around it ? $\endgroup$ Sep 22 '17 at 1:05
  • $\begingroup$ @AnantTripathi Earth "pulling" the space in around it is gravity - mass and energy just warp space time, and it is this that we perceive as gravity. $\endgroup$ Sep 23 '17 at 0:25
  • $\begingroup$ You mean gravity is a phenomenon of earth not the space time ? $\endgroup$ Sep 23 '17 at 2:53
  • $\begingroup$ @AnantTripathi, no, not quite. Mass and energy "warp", that is, bend or "suck in", spacetime. That is what we see as gravity. If there was no mass or energy, then we'd see no gravity (well, we'd be mass, so we would, but if we were massless or observing from outside the universe we wouldn't). $\endgroup$ Sep 23 '17 at 13:36

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