Chris wrote:
It is also false to suggest that there is no evidence of a supermassive black hole in the LMC. While none has been detected directly, we know of a star that was ejected from the LMC and- to date- only a supermassive black hole interaction can explain that.
I will not argue about the math underlying that claim.
My point is that black holes arise out of mass concentrations. My gut feeling, for what it is worth, is that huge mass concentrations more easily occur when there is a lot of free gas available, than when most of the gas has been turned into stars. That would make the LMC a pretty fertile ground for black hole making. The Tarantula Nebula and R136 anyone?
On the other hand, I wouldn't expect the LMC to ever form a black hole the mass of the Milky Way's central supermassive black hole. The LMC doesn't pack the punch, or more importantly, the
mass to do that.
When really supermassive black holes have been found in quite small galaxies, I believe we are mostly talking about galaxies that for some reasons have lost most of their "outlying mass", so that only the inner bulge is left. The tiny dwarf galaxy
M60-UCD1, whose mass is only 1/1000th of the mass of the Milky Way, nevertheless contains a central black hole of 21 million solar masses, more than five times the mass of the central black hole of our own galaxy.
But M60-UCD1 is clearly a galaxy that has been robbed of most of its mass by its big bully neighbor, M60. So having a monstrous central black hole didn't help M60-UCD1 hold on to its mass.
Ann