SANTA BARBARA—Physics has always been one of the most globalized of professions. Physicists think of themselves as supranational, rising above national and cultural concerns. They may not always live up to this ideal, but at least they try. I got a glimpse of this as a college student in 1987 when I spent my spring break at Bell Labs. High-temperature superconductors had just been discovered, and I had some fun levitating magnets (and collaborated on a published paper). Over lunch, the talk turned to poking holes in the Iron Curtain. Lab scientists were making contacts with colleagues in the Soviet Union, organizing joint conferences and translating articles from or into Russian. They told me stories about Andrei Sakharov and Pugwash conferences, which brought together scholars from all countries to work toward nuclear disarmament and later won a Nobel Peace Prize.

This idealistic urge remains powerful. A few weeks ago at the workshop I'm attending on black holes, I talked to Eliezer Rabinovici, a theoretical physicist at the Hebrew University in Jerusalem. He and his colleagues may well be the only people on the planet to have gotten Arabs, Iranians, Turks and Israelis to agree on anything. Nearly every country in the Middle East has signed onto their project to build a particle accelerator for joint use: SESAME. The decades-long effort has made understanding the nature of space, time, and matter look trivial.

"I had a vision to try and work with our neighbors, to do something for our common humanity," Rabinovici says. "That sounds bombastic, but that's what SESAME is all about."

Born in Jerusalem in 1946, Rabinovici has been reaching out for much of his professional life. He lobbied the Israel government to reopen Palestinian universities it had shut. He worked with the Middle East Scientific Collaboration, an organization founded by Italian theoretical physicist Sergio Fubini, to organize a physics conference in Egypt in 1995 attended by the likes of Ed Witten, Roman Jackiw and Giovanni Veneziano. In a Bedouin tent in the resort town of Dahab (shown in the photograph above), Arabs and Israelis alike stood in honor of Yitzhak Rabin, who had been assassinated three weeks before.

"But then the buses began to explode," Rabinovici recalls. With the resumption of terrorism and war, the conference proved a one-off. Individual scientists could no longer commune without taking their lives into their hands. Rabinovici and his colleagues wove together a network of high-level political patrons and got the project back on track with a concrete offer of a hand-me-down synchrotron from the German laboratory BESSY. Once everyone was on board, they ratcheted up their ambitions to a brand-new instrument.

The SESAME project has managed to hang together despite the tumult of the past two decades. It chose a laboratory site in Jordan in 2000, built the building in 2008, and settled on the synchrotron design. It is not really a particle physics project, but a general source of radiation for chemistry, biology, pharmaceutical development and other fields—a diversity that is matched to region's needs.

In March, the Iranian, Turkish, Jordanian, and Israeli governments pledged $20 million for the main accelerator. The project has now gone cap in hand to the U.S. and European Union for the balance, about $15 million. He laments that the E.U. in particular has been dragging its feet: "They lecture Israel, yet fail to follow up."

In 1954 European scientists founded CERN so that German, French, British and other ex-adversaries would have a place to shoot particles rather than bullets. "It was one of the places where Europe was reborn," Rabinovici says. SESAME arguably has the tougher task, since the adversaries are not yet "ex". Another Israeli theorist, Ramy Brustein, compares it to "climbing on an ice wall." But in 1987, everyone thought the same of cultural exchanges across the Berlin Wall.

Eliezer Rabinovici at Dahab physics conference, November 19, 1995. Courtesy of Eliezer Rabinovici