How can we visualize gravity in 4D spacetime?

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How can we visualize 4D spacetime and how gravity plays a role in 4D spacetime??
 
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hover said:
How can we visualize 4D spacetime and how gravity plays a role in 4D spacetime??

This is a FAQ; did you try searching for previous PF threads? This very question was discussed as recently as a few days ago.
 
If you take and combine two of the spatial dimensions say z and y then have time be your third dimension on a graph it is pretty easy. Its used in a lot of examples and what not in books.
 
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Thread 'Dirac's integral for the energy-momentum of the gravitational field'

Thread 'Dirac's integral for the energy-momentum of the gravitational field'

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Thread 'A sufficient condition for integrability of equation ##\nabla g=0##'

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