Trouble Understanding GRT & Space-Time Attraction

[AmorLiberalitas]

How can the distortion of space-time by matter lead to the attraction of two objects in space? What I mean is on a 2D plane representing space-time, a 3D object representing a planet can cause the geometry of space-time to warp, and that a passing smaller 3D object will spiral around the larger because of the ripple it makes. However, what I do not understand is how the two-dimensional analogy can be transferred into the three-dimensional world that we inhabit. I guess what I am trying to say is how does the curvature relate to us, are we pulled down by earth, are we pushed down by warped space-time? Sorry if none of this made sense. . .

 

[Schrodinger's Dog]

Space-time is 4 dimensional not two dimensional: with (x,y,z and t) I think you need to see the fabric of space as 3D rather than 2D, otherwise you'll confuse yourself. It is true that GR only works if we assume a flat space in terms of acceleration and gravity, but this is not what actually happens and is one of the reasons why relativity is not compatible in certain cases with quantum mechanics.

This picture might help.

https://www.physicsforums.com/attachment.php?attachmentid=9183&stc=1&d=1171663113

Similar questions that might help.

https://www.physicsforums.com/showthread.php?t=154960

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[Entropia]

Understanding the concept of General Relativity Theory (GRT) and space-time attraction can be quite challenging, so it is normal to have trouble grasping it. To answer your question, let's start with the basics.

According to GRT, gravity is not a force between masses, but rather a curvature of space and time caused by the presence of matter and energy. This means that objects with mass create a distortion in the fabric of space-time, and this distortion is what we experience as gravity.

To understand how this distortion leads to the attraction of two objects in space, let's use your 2D analogy. Imagine a flat sheet representing space-time, and a heavy ball placed in the center of it. The ball creates a dip in the sheet, causing it to curve downwards towards the ball. This curvature is what we experience as gravity, and it affects everything around it, including smaller objects.

Now, if we place a smaller ball on the sheet, it will follow the curvature and spiral around the larger ball. This is because the smaller ball is moving in a straight line in the curved space-time, giving the illusion of being pulled towards the larger ball.

In the 3D world, the same concept applies. The Earth's mass creates a curvature in space-time, and we are constantly moving in a straight line in this curved space-time. This gives us the sensation of being pulled towards the Earth, but in reality, we are just following the curvature of space-time.

To sum it up, the curvature of space-time created by matter is what leads to the attraction of two objects in space. And in the 3D world, we experience this attraction as gravity. I hope this helps clarify your understanding of GRT and space-time attraction. Keep exploring and asking questions, as it is the best way to deepen your understanding of complex concepts like this one.