Unless its a tachyon blackhole.That would only make sense if he'd done it before the supernova happened and vaporized Romulus. The problem with the movie's story is that he still tried to do it afterward, when Romulus was already gone.
The claim was that he was trying to protect other systems from the blast, but that doesn't make any sense. It's like trying to defuse a bomb after it's blown up. The blast wave and radiation have already gone out, expanding away from the site of the explosion. Nothing you do at that site after the fact is going to suck it all back in.
The whole shit with red matter is so floaty it can be anything.