What was going on when I was born?

Stock prices plunged yesterday on apprehension over rising interest rates. Trading remained light. The Dow Jones industrial average finished with a drop of 15.64 points, to 1,115.61, after moving lower most of the day. It was the biggest daily drop in the average since May 4, when it fell by 16.22 points.

An article May 17 on school desegregation since 1954 erroneously described the status of desegregation orders in Cincinnati and St. Louis. In an agreement reached in February, Cincinnati's board of education and the state of Ohio agreed to share the costs of a court-ordered plan equally, and the school district is not appealing the order. The state of Missouri has appealed a consent decree on desegregation in the St. Louis metropolitan area; the St. Louis school board has not appealed, and the plan is operating.

An experimental antiballistic missile has accomplished the first direct interception and destruction of an incoming dummy missile warhead, Army officers reported today. On Sunday, the non-nuclear missile was lofted into space where it unfolded an umbrella-like device 15 feet across that collided with the test warhead, the Army officers said. The interceptor, fired from Meck Island in the Kwajalein Islands, met hundreds of miles away over the South Pacific with the dummy warhead fired from a Minuteman 1 intercontinental missile launched from Vandenberg Air Force Base in Southern California. Encouragement for Space Plan Army generals made no sweeping claim, emphasizing that the experimental missile did not constitute a working weapon system. But the success of the interception over the Pacific Ocean Sunday seemed sure to encourage advocates of President Reagan's proposal to seek a defense against ballistic missile attack.

A New York State court yesterday declared invalid a state law that prohibits liquor stores from selling liquor at less than a minimum retail price. The court, the Appellate Division of State Supreme Court in Brooklyn, ruled that the state law prescribing a price-floor system in the retailing of hard liquor for off-premises consumption violated Federal antitrust laws. State Liquor Authority officials said that they would appeal the case to the state's highest court, the Court of Appeals, and that until that court acted, the ruling would not be enforced. Elsewhere in the country, 18 states regulate the price of liquor by selling it themselves at the wholesale or retail level. Like New York, both New Jersey and Connecticut are among the 32 states in which wholesale and retail liquor sales are run by private enterprise and regulated by the state.

What do you do with an exotic metal alloy that has the ability to ''remember'' its original shape and return to that shape when heated? In the United States, the answer is: Use it to make pipe joints in fighter planes and think about using it for satellites that could be launched in compact form and would unfold automatically in space. But in Japan, the answer is: Use the alloy to make eyeglass frames, air-conditioner louvers and a toy in which a boy's head and a girl's head are separated by a wire made of the alloy. When the toy is dunked in hot water, the wire returns to a ring shape, bringing the heads together in a kiss.

LAST November, a month after his 17th birthday, Clinton Langston quit high school because he thought he was not getting anywhere. He was in the 10th grade and his reading and mathematics scores were still at the elementary school level. ''I saw I was getting older and that I was not doing anything with my life,'' said Mr. Langston, who conceded that he attended classes at Sarah J. Hill High School in Brooklyn only when he felt like it. Now, Mr. Langston is in the Board of Education's Auxiliary Services program preparing to try to get his high school equivalency diploma through the General Educational Development examination, known as the G.E.D. The State Education Department, in recognition of the plight of thousands of students like Mr. Langston, has proposed revamping high school equivalency programs to more readily accommodate people under the age of 19. Last year, 490,329 Americans obtained high school diplomas by passing the equivalency test, and the vast majority were older than 19.

The Monday Sports listing yesterday misidentified Doug Williams. He plays for the Oklahoma Outlaws and has been sidelined by injury.

Most of the 500 to 600 Sikh troops who deserted in northeastern India on Sunday were arrested today at three places, including one where a gun battle left 26 Sikh extremists dead, Indian news agencies and officials reported tonight. At the same time, more defections and attempted defections were reported in the north and in the west, near Bombay. The Press Trust of India reported 574 arrests at points between Ramgarh and New Delhi, and an army spokesman said that if the report was accurate ''that should take care of all the deserters.'' He said he could not confirm the report. Angered by Temple Assault The Sikh soldiers deserted Sunday at Ramgarh in Bihar State in anger at the Indian Army's assault last Tuesday and Wednesday on the Golden Temple in Amritsar, Punjab, the holiest site of the Sikh religion. The soldiers joined other Sikhs in heading across India for Amritsar.

Argentina today submitted its own austerity program to the International Monetary Fund, in defiance of harsher proposals sought by the fund. The austerity program is intended to help the country repay its huge foreign debt. The six-month-old civilian Government of President Raul Alfonsin sent a letter describing its unilateral program to the fund's managing director, Jacques de Larosi ere, after it had been unable to reach an agreement with I.M.F. negotiators here. Economy Minister Bernardo Grinspun, who signed the letter, said Argentina would oblige Mr. de Larosi ere to follow the I.M.F.'s regulations and submit the letter to its 21-member executive board, where Argentina hopes to apply political pressure on the United States and other governments to accept the Argentine terms.

Enrico Berlinguer, the Italian Communist leader who started a movement among Western European Communists toward greater independence from Moscow, died yesterday at a hospital in Padua, Italy. He was 62 years old. The leader of Western Europe's largest Communist Party for the last 12 years, Mr. Berlinguer nearly brought it to power in the Italian parliamentary elections of 1976. He suffered a stroke in Padua on Thursday while delivering a speech and died in the hospital without regaining consciousness. President Sandro Pertini, who had flown to Padua to be with the dying Communist leader, took the body home in his plane. At Rome's Ciampino Airport, mourners waved red flags and chanted ''Enrico, Enrico!'' as the coffin was placed on a hearse. Near the Piazza Venezia, 2,000 people watched it being carried into party headquarters.

AN IMPATIENT young weapons designer wrote to Dr. Hans A. Bethe not long ago, urging the eminent physicist to stop his opposition to the development of a new generation of nuclear weapons. ''Look here, you were very enthusiastic when you made the atom bomb, even though there were some old people who said it couldn't be done,'' the young physicist wrote the elder one. ''Now don't tell us the same thing. We want to have our chance.'' The young physicist's frustration over the opposition of Dr. Bethe (pronounced BAY-ta) is not an isolated case. His feelings are shared by many of the young scientists at work at national laboratories on what they regard as the next generation of nuclear weapons - those designed to be used as a ''defensive shield'' in space.

Walter F. Mondale's rivals for the Democratic Presidential nomination showed little interest today in challenging him on the platform to be adopted at the party's national convention. In separate appearances before the convention's 184-member platform committee, Senator Gary Hart and the Rev. Jesse Jackson both emphasized the need for defeating President Reagan in November, called for Democratic unity to promote that goal and generally minimized their differences with Mr. Mondale on issues. After the primary competition ended last week, Mr. Mondale said he had a majority of the 3,933 delegates who are to attend the convention next month in San Francisco. Several independent compilations have confirmed his statement.