Black hole Lecture at Bronx Science

[AINEWSNOW]

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[shawns]

Relativity does not predict singularities/black holes. Einstein wrote in 1939 -
"The essential result of this investigation is a clear understanding as to why the Schwarzchild singularities (he was the first to raise the issue of General Relativity predicting singularities) do not exist in physical reality. Although the theory given here treats only clusters (star) whose particles move along circular paths it does seem to be subject to reasonable doubt that more general cases will have analogous results. The Schwarzchild singularities do not appear for the reason that matter cannot be concentrated arbitrarily. And this is due to the fact that otherwise the constituting particles would reach the velocity of light."
He was referring to dilation. It's the phenomenon our high school teachers were talking about when they said "mass becomes infinite at the speed of light". This does not mean mass increases, it means mass becomes spread throughout spacetime relative to an outside observer. Time dilation is just one aspect of dilation. Even mass that exists at 75% light speed is partially dilated.
It occurs wherever there is an astronomical quantity of mass, this includes the centers of high mass stars and the majority of galaxy centers.
Dilation is occurring in our own galactic center. This means that there is no valid XYZ coordinate we can attribute to it, you can't point your finger at something that is smeared through spacetime. In other words that mass is all around us. It's the "missing mass" needed to explain galaxy rotation curves.
It doesn't occur in galaxies with low mass centers because they do not have enough mass to achieve relativistic velocities. It has recently been confirmed in 6 ultra diffuse galaxies including NGC 1052-DF2 and DF4 to have normal rotation rates, in other words they have no dark matter/dilated mass.