It’s Cold & It’s Dark, But Does it Matter?
According to a paper posted to the arXiv pre-print server last week, the difference between an everyday supermassive black hole and a space-time tunneling wormhole may be a lacing of dark matter. While it sounds like crank fodder of the sort that not infrequently winds up on arXiv, the idea may hold actual water (actually, it condenses it!).

Branes Bring Rain