Sources containing neutron stars, the dense cores of dead stars that would be the alternate explanation for these observations, do not show characteristics simultaneously. (ibtimes.com)
One new idea is that the very first black holes did not form from dead stars at all; instead, they formed directly from the collapse of huge amounts of gas. (kavlifoundation.org)
There might be a massive, dead star out there that bends the stuff of raw vacuum and prevents itself from collapsing into a black hole. (space.com)