A senior Soviet scientist broke ranks with his tradition and privilege today in an unusual and wrenching denuniciation of restrictions placed on his professional and family life by the Soviet state.

Sergei M. Polikarpov, a nuclear physicist who is both a corresponding member of the prestigious Academy of Sciences and a long-time Communist Party member, said he was driven to speak out to Western reporters after many unsuccessful attempts to be allowed to pursue his research in Switzerland with scientists from capitalist countries.

The physicist, an internationally known researcher into the composition and structure of the atomic nucleus, said unknown Soviet authorities have ruled that if he went to Switzerland to work for a year on the unique research that has preoccupied him for the past 15 years, he could not take his family with him.

In a letter intended for a senior member of the European Organization for Nuclear Research, polikarpov said he believes he was turned down because an informer wrote a letter to the KGB, the state secret police, accusing Polikarpov's wife of being suspect.

"Isn't it surprising because she doesn't work and doesn't possess state secrets?" he wrote in the letter, which he gave to Western reporters last night. "However, she does not express delight at the empty counters of our shops. Some informant has written information. . . It's a very simple story, isnt's it? And very disgusting."

Polikarpov's bitter complaint gives a rare view into an area of Soviet life seldom seen by Westerners, a world where political thought and loyalty to the state come into conflict with the pursuit of science.

Polikarpov said his difficulties began more than two years ago, when he was invited to Geneva to continue his work. The physicist, 51, is head of the Department of Atomic Nuclei at the well-respected Dubna Nuclear Research Institute outside Moscow. According to Polikarpov, his original theories, which he first began defining in 1962, have led nuclear physicists to sharply revise their concept of the shape of the atomic nucleus. These revisions have led to new theories about the nature of nuclear fission, the elemental splitting of the atom that releases stupendous energy and produces both peaceful nuclear power and the atomic bomb.

He said his application for permission to take his wife and daughter, then 16, to Geneva was refused.

"It would be very hard to stay in Switzerland without my family for those long months and I refused for this reason," he wrote.

Late, he sought permission for a two-week visit alone. This also was refused. Meanwhile, the SOVIETS HAVE shipped to Geneva most of the complex machinery which his department designed to investigate his theories. There, other scientists will be able to proceed without him toward a solution to his work.

"What was my fault?" he wrote. "Only that I loved my wife and daughter and I don't want to live apart from them for a long time. I prize everyday with my family."

"I have been told we have a lot of scientists who have been told they cannot go to capitalist countries. I am surprised there is not more protest, but they fear repercussions."

The scientist, of medium build with the air of a general college chemistry instructor, declared: "Isn't a man in charge of his own fate? Is my wish to cooperate with Western scientists criminal? How can someone unknown to me decide how I will live my life?"

In his letter, he touched on other, more sensitive issues present within Soviet culture - anti-Semitism, Xenophobia, public intoxication.

"My biography had no aggravating circumstances. I am not a Jew, but a Russian. I do not have relatives abroad. I was not on German soil in wartime. I have noteven been in a sobering-up station."