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.
 
comparing a flat solar panel of area 2π r² and a hemisphere of the same area, the hemispherical solar panel would only occupy the area π r² of while the flat panel would occupy an entire 2π r² of land. wouldn't the hemispherical version have the same area of panel exposed to the sun, occupy less land space and can therefore increase the number of panels one land can have fitted? this would increase the power output proportionally as well. when I searched it up I wasn't satisfied with...

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