When the radius of earth re is shrunk to reo = 0.00886 m light will not escape from it. The actual gravity of such a black hole is,
g=−Go(x+reo)2
geo=−Gor2eo = -5.07071e18 ms-2
And the corresponding gravity equation is,
g=−geoe−georeoGo(x)
The corresponding time dilation field equation γ(x) is,
γ(x)=√1−2Goc2reoe−georeoGo(x)
2Goc2reo=1
georeoGo=1reo = 112.86681715575618 m-1
γ(x)=√1−e−112.866x
This is a graph of time dilation γ(x) = (1-e^(-112.866*x))^(0.5) around a black hole. Time returns to normal very quickly at about 0.065 m. So much for time travel around a black hole; a 6.5 cm disk around which time dilation occurs is way smaller than expected.