How does the density of a neutron star compare to that of a black hole?
Density of neutron star: around 10^17 to 10^18 kg/m^3 Density of black hole: … Tricky … Problem is GR says the size in comoving coordinates is zero so density is infinite. QM says it can’t be infinite but must have some finite size. But it must be very small. Perhaps of the order of 10^-35m. Which would make the density of a small black hole around 10^135 kg/m^3 A mere 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 times denser.
