Why Can't There Be Gravity in 2 Spatial Dimensions?

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Gravity cannot exist in two spatial dimensions due to the requirements of general relativity (GR), which states that a gravitational field necessitates curved space. In two or three dimensions, it is impossible for the Einstein field equations to be satisfied in a vacuum while allowing for curvature. This leads to the conclusion that a non-zero gravitational field cannot exist in empty space in those dimensions. The gravitational law would also differ, potentially becoming an inverse-law rather than an inverse-square law. Overall, the nature of gravity and the structure of space-time in lower dimensions remain unresolved and speculative.
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Why do they say there can there be no gravity in 2 spatial dimensions (and 1 temporal dimension)?

wouldn't the gravitational law be an inverse-law instead of an inverse-square law?
 
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lolgarithms said:
Why can there be no gravity in 2 spatial dimensions (and 1 temporal dimension)?

I don't think anyone clearly proved that there couldn't be (as far as I know). Not to mention, gravity is still relatively mysterious to us, so we don't know enough to assert whether there is or is not any gravity in 2 spatial dimensions.
 
According to GR there can not be a non zero gravitational field in empty space in two or three dimensions. For a gravitational field in a region it is necessary that space is curved. But in 2 or 3 dimensions it is not possible for the Einstein field equations to be satisfied in a vacuum and for space to be curved. In 4 dimensions there are a lot more independent components of the curvature tensor which means that space can be curved whilst still satisfying the field equations in empty space.
 
So I know that electrons are fundamental, there's no 'material' that makes them up, it's like talking about a colour itself rather than a car or a flower. Now protons and neutrons and quarks and whatever other stuff is there fundamentally, I want someone to kind of teach me these, I have a lot of questions that books might not give the answer in the way I understand. Thanks

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