Tag Archives: Cosmology

Black Holes Only Grow So Big

A few weeks ago there was a fairly cool paper on arXiv that suggested that supermassive black holes may only be able to grow so big. This triggered several Astronomy Cast listeners to write and basically say “Huh?” We addressed this a little bit in today’s questions show (real show to follow tomorrow or Wednesday […]

Ghosts are NOT Dark Matter

Just a quick one tonight. At Dragon*Con (which I won’t mention again until next summer) some fascinatingly misguided person suggested that ghosts are made of Dark Matter. Dark matter is the missing 22% of the stuff the universe is made of. This is stuff – it is just stuff that doesn’t interact with the electromagnetic […]