Does antimatter fall up?

We'll be abe to know soon. [Link]

Antihydrogen is rare in our part of the Universe. Indeed, it was only last year that scientists at CERN's Antihydrogen Laser Physics Apparatus (ALPHA) managed to trap a significant amount of the stuff for the first time, albeit only 38 antiatoms for just 172 milliseconds.

Today, they announce a significant improvement. These guys now say they've trapped 309 antihydrogen atoms for up to 1000 seconds. That's an increase in trapping time of four orders of magnitude, comparable to what's possible with good old ordinary matter.

The news is significant because it makes possible a new set of experiments that should answer some important questions.

Most important of these is whether ordinary gravity attracts or repels antimatter. In other words, does antihydrogen fall up or down?

Although there have been many attempts to do this experiment, all have been inconclusive because nobody has been able to trap a good lump of antimatter for long enough to try.