I have come to the viewpoint that as the earth has a molten core at 6000 C which is the same as the surface of our sun and a cooled mantle can form , a super massive sun (black hole) could potentially form a mantel around it also. Such a super-mass migt be up to or more than 20 Billion times bigger in mass than our sun but I see nothing that would stop this . Perhaps its not light being bent back , but that, really , no light gets out