They are a marriage of differences. He's American, she's Israeli. He's a physicist, she's an anthropologist. He's black, she's white.

They are also a couple pitted against the complexities and curiosities of the federal bureaucracy. Smadar Lavie, a Fulbright scholar, has been told that her Fulbright requires her to return to Israel for two years. But she says she didn't know about the rule until after she had married an American graduate student at Berkeley.

The couple says that the U.S. Information Agency, which recommended against granting Lavie a waiver, is trying to make an example of them.

"They think I came here, planned to get a job by grabbing a guy and marrying him and applying for the waiver," says Lavie, 31.

"I have fallen into a little known crack in our immigration law," her husband Forest Rouse, 30, wrote in a letter to President and Nancy Reagan, "where love and family don't matter, nor do the opinions of two U.S. senators, a Nobel Laureate, the state of Israel, and even our own INS Immigration and Naturalization Service ."

The USIA is not unaware of all this, including the fact that the couple applied for a waiver to the residency requirement on grounds that Rouse would face a hardship if he accompanied his wife to Israel: He would be unable to continue the kind of scientific research he has been doing. In May 1984, the INS ruled that a hardship did exist for Rouse, but INS will not grant a waiver without a recommendation from the USIA. And in November 1984, USIA vetoed such a waiver.

"We agonize over each decision," says USIA Assistant General Counsel Richard Fruchterman, who is in charge of reviewing waivers filed by exchange visitors. "They're tough. We know we're dealing with people's lives. But we want people to know when they accept a Fulbright grant, the purpose is to get the education and return to your country and put it to use. We're not going to let the Fulbright program become a vehicle for avoiding normal immigration laws of the U.S."

So Lavie got the Israeli government to issue a statement of "no objection" to her not returning for a residency requirement. And her doctor wrote to the USIA last summer, saying the stress of all this had taken its toll on her health -- she had developed endometriosis. Rouse and Lavie even visited Washington in the winter to personally plead their case before Fruchterman. But no go.

As long as Lavie is studying, Berkeley officials make sure her visa is renewed each year. But when she finishes her PhD -- 12 to 18 months from now -- she will have to return to Israel, according to the Fulbright stipulation. Rouse is half a year from finishing his PhD, and then he enters the competitive race for postdoctoral appointments.

"I'm sixth-generation Israeli," says Lavie. "It's not the 'wandering Jew' syndrome, looking for the best place to be. . . . It's just that I met this wonderful guy. What can I say?"

started like this:

Seven years ago, Lavie, an anthropology student at Hebrew University, was wandering through the Sinai desert with Bedouin tribes, working on a project for the Desert Research Institute. The Israel America Cultural Foundation in Israel managed to catch up with her to tell her she'd won a grant.

* She had already been accepted at the University of California, Berkeley, for graduate work in anthropology, with the school paying tuition and a living stipend. The Fulbright paid for her round-trip ticket -- $1,500, Lavie said.

Lavie started her graduate work in the fall of 1979, and met Forest Rouse three years later when he moved into her Berkeley apartment house. She thought he was weird. He thought she was an Israeli left-winger.

*Their courtship was rocky. Once they went to a jazz club and Rouse spent the whole time in brooding absorption, head cradled between his arms.

"He didn't have many social skills," Lavie says.

Months later, they went to have a drink at the Berkeley marina. They talked about their lives. Lavie's mother is Yemenite and her father was Lithuanian, and growing up in Israel, "I felt like a fence sitter -- like I didn't belong where I was," she says.

"We decided we had grown up in the same way for the same reason in different cultures," says Rouse, reflecting upon growing up black in America. "The way my parents handled it was like, 'Let Forest handle it himself.' "

"And my parents said, 'Be super social and super good, let everyone like you,' " says Lavie.

"So she was social and I was reclusive," he says, "but we had very similar experiences."

They were married on Oct. 18, 1983. They wore matching white T-shirts reading "Generic Play" ("it's my comment on the institution of marriage," Rouse says) before a judge who took one look at them and said, "You must be from Berkeley."

Shortly after their marriage, Lavie was about to apply for permanent resident status here when she called the adviser of foreign students and scholars for her records. That's when she found out she might have a problem.

"I remember the shock when I told her I thought she was subject to the residency requirement," says Lawrence DiCostanzo, an attorney specializing in immigration whom Lavie sought out.

The issue of whether Lavie should have known was quickly becoming irrelevant. The new focal point was the waiver and soon after the meeting with DiCostanzo, a potluck supper to celebrate Lavie and Rouse's marriage turned into an apologetic fundraiser: "As you may or may not know," the invitation read at the bottom, "there is one person who won't be at the potluck who also needs to be fed: our immigration lawyer."

Together they are a chaotic, cheerful, noisy fusion of cultures and personalities.

Their conversation is a game of bumper pool, Lavie racing through her thoughts in words filled with emotion and frustration and overbearing detail while Rouse, sensing confusion as the only result, rushes to overtake her with his precise explanations. Then suddenly, they collide, equally frustrated by their situation.

"It's an extremely complicated case," says Rouse. "For us, we live it, so it comes gushing out."

What's so hard about two years in Israel? The couple's answer: It would be disastrous for Rouse's career.

*Rouse is close to getting a PhD in experimental particle physics at Berkeley, after which he will seek a postdoctoral appointment at a university. His work is centered on a state-of-the-art particle detector called the Time Projection Chamber at the Stanford Linear Accelerator Center. There's nothing like it in Israel.

"Two years spent away from this fast-moving field will leave Mr. Rouse at a grave disadvantage in the field and in career opportunities," Gilbert Shapiro, a Berkeley professor who is Rouse's adviser, wrote in a 1984 letter to the INS. The Nobel Prize-winning Berkeley physicist Owen Chamberlain wrote to the agency in a similar vein.

*"The bottom line in this case is that we can't really figure out why the waiver was denied," says DiCostanzo.

But USIA's Richard Fruchterman can:

"Every time someone comes to this country to study at U.S. government expense and doesn't return to their own country, the whole purpose of the exchange program is frustrated," says Fruchterman.

In early 1985, 11 physicists -- including Shapiro and Chamberlain -- wrote to Sen. Alan Cranston (D-Calif.) asking him to intervene. All emphasized what a hardship the two-year leave would be for Rouse; Berkeley professor of physics Gerson Goldhaber went so far as to say "it would mean the end of Forest's career as a particle physicist." And a number emphasized that this was particularly unfortunate because Rouse was one of the few blacks in PhD physics programs in the United States.

In the end, Cranston got essentially the same answer from USIA that Rouse and Lavie got.

Fruchterman remains unmoved. At a December meeting here, Fruchterman told Rouse and Lavie that lots of couples had to be physically separated and cited himself as an example. He was separated from his wife while in the Navy. "It's not impossible," he says of Rouse and Lavie. "They can go visit."

And, the couple contends, Fruchterman cast aspersions on the sincerity of interfaith, international couples requesting waivers.

"We walked out of that meeting and we were absolutely flabbergasted," says Rouse.

Fruchterman says he cast no aspersions on their marriage. "I mentioned that we had cases between Arabs and Jews. I'm sure I inferred at least that there are some marriages of which I am suspicious. I'm convinced that this Rouse and Lavie's is not a fraudulent marriage."

He is unimpressed by Lavie's argument that she would not be able to find a job in Israel in her field.

"Then she shouldn't have come to this country and studied what she studied," he says. "I hear that six times a day. She's not unique."

Out of an approximate 1,200 waiver applications a year, a little more than half get approved. But, Fruchterman argues, Congress did not intend a lenient waiver policy for exchange visitors -- particularly where U.S. funding is involved.

"I have to answer 20 congressional inquiries a month," says Fruchterman. "When a federal agency gets an inquiry, everything stops so it can be answered . . . If I didn't think I was right, I could avoid all that. I don't enjoy answering congressional correspondence."

Marvin Baron, the deputy director of the Berkeley office that advises foreign students, says that it's always been difficult to get a waiver -- but this case stymies him.

"There is no national purpose being served by forcing Smadar Lavie to leave the country," says Baron, who has been advising foreign students for 25 years. "I don't think it will . . frighten Israelis or others from trying to get waivers . . I don't think it's going to serve any purpose at all other than making a couple of people very unhappy."