Seven Harvard scientists, including graduate students and post-doctoral fellows work with Gabrielse in Geneva.

Their success in creating anti-hydrogen, the simplest form of anti-matter, was published in the journal Nature in October.

The Gabrielse team, which goes by the name of Antihydrogen Trapment Collaboration (ATRAP), was able to create an atom of anti-hydrogen, the anti-matter counterpart of hydrogen, by joining an antiproton, the counterpart of a proton, and a positron, the counterpart of an electron. Except for their charges, both the anti-proton and the positron are identical in nearly all respects to their antimatter counterparts.

The most difficult part of creating anti-hydrogen involves overcoming repulsive forces to bring together the oppositely-charged antiproton and positron.

A machine the size of a football field uses magnets to guide anti-protons into and positions together. When the two get close enough, anti-hydrogen forms.

The Competition

But ATRAP wasn’t the first to succeed.

A few weeks before, on Sep. 18, a competing group, called ATHENA, which also uses the accelerator at CERN, announced that they had succeeded in joining an antiproton and a positron. This group is composed of mainly European scientists, who had not been serious competition for the Harvard group before.

However, Gabrielse said that ATHENA’s success came in part from work Gabrielse had already done. He said that many of the devices and techniques used by ATHENA to create the anti-hydrogen—including the football field-sized machine used to trap and merge antiprotons and positrons—had been developed by ATRAP in years earlier.

“In science, first and second is always a little tricky,” he said. “I don’t think anyone really disagrees that the main techniques in the experiment are the ones that we have developed.”

ATHENA member Alessandro Variola, a scientist from the Italian National Institute for Nuclear Physics (INFN), says that such borrowing of techniques from other scientists is a natural and necessary component of scientific progress. “You can mix a huge amount of…different experiences, different techniques. You must be careful to choose the techniques that allow you the best [results],” he says. “And surely, some of the techniques of Dr. Gabrielse were useful for us.”

He also said that ATRAP and ATHENA experiments differed in several notable ways, including in methods of detecting the anti-hydrogen after creation and in the quantity of positrons used.

Gabrielse said that ATRAP had begun its anti-matter experimentation long before ATHENA.

“That was laid out about five or more years before ATHENA even existed,” he says. “They basically bought into the vision.”

Because ATRAP had been foremost in many technological innovations for the project, according to Gabrielse, it had been seen as the clear leader in anti-matter resarch—until Sept. 18.