Contrary to Einstein's conclusion that gravity is a curvature in four-dimensional unit space, the statistical theory of Cairo techniques shows that gravity is a true force (like the famous Cavendish experiment) causing a curvature of space and not the other way around.
There are two theories of general relativity:
1- A. Einstein's classical theory of general relativity.
2- The modern theory of general relativity, derived from the statistical theory of Cairo techniques.
The statistical theory of Cairo techniques shows that the symmetric stress tensor in free space is given by:
∇^2 xx ∇^2 xy ∇^2 xz ∇^2 xt
∇^2 yx ∇^2 yy ∇^2 yz ∇^2 yt
. . .
etc.
For the special case of the gravity tensor, it is straightforward to show that the factor (8πG/c^4) must be introduced to obtain Einstein's classical expression:
G_μν = (8πG/c^4) T_μν.
We again have two distinct theories of general relativity.
1- A. Einstein's classical theory of general relativity.
2- The modern theory of general relativity is derived from the statistical theory of Cairo techniques.