KOVALEVSKY, Som's1L VASILYEVNA, better known under her pen-name, 'SONYA' ( 1830 91). An eminent Russian mathematician and author, the daughter of General Korvin-Kru kovsky. She was born at Moscow and brought up at Palihino, her father's estate, in the Government of Vitebsk. When in 1865 Stran nolyubsky began to teach her calculus at Saint Petersburg. he was amazed at her quickness. About 1867 she and her sister, later a well known novelist, resolved to go abroad to study. To obtain independence for the purpose a sham marriage, such as was of daily occurrence among Russian youth at this period, was decided upon. A student, Vladimir Kovalevsky, when asked to act as the fictitious husband to give Sonya's sis ter the necessary legal status, consented on the condition of marrying Sonya herself. In October. 1868, the ceremony was performed, and the three went abroad the following spring, when Sonya's husband took up geology at Jena. In 1869 she studied mathematics at Heidelberg. eliciting the warmest praise from K.(1nig.sherger and Kirch hoff. In the autumn of 1870 she went to the University of Berlin, where no women were ad mitted. At a perfunctory test at his house. the great Welerstrass was astounded by her lucid and original solutions of the problems that at the time engaged his most advanced pupils, and henceforth he guided her studies for three years. In 1874 she received the degree of Ph.D. at the University of Glittingen on the basis of her mem oir, Zur Theorie der partiellen Diffcrentialglcieh ungen. After receiving their degrees, Sonya her husband lived together until he became in volved in speculations in house-building. news paper-publishing, petroleum-wells, etc. The couple parted, and Sonya went abroad to make for her self a name in science. lint her husband's death, which followed shortly, was a crushing blow to her, and she resumed scientific work only after a lingering illness. In 1883 Mittag-Leffler, a pupil
of and rector of the University of Stockholm, obtained for her a docentship. After a year of lecturing in German she was ap pointed professor of higher analysis for five years, on condition of teaching in Swedish. In 1888 she received in person the Prix Bordin (doubled to 5000 francs) of the Paris Academy of Sciences for her Nur ten cos partieulier du pro blemc de la rotation d'un corps pesant autour drum point hid. For two other essays, the Stock holm Academy awarded her a prize of 1500 kroner in 1SS9. Besides, she contributed a num ber of important papers to scientific periodicals. She had, moreover, literary abilities in addition to her mathematical talents. Lt 1877 she wrote The Pricatdoeent—a sketch from the life of a small German university town—which met with a hearty reception. lIer Recollections of Childhood, published in a Itussian magazine (1890), aroused widespread attention. In Sweden she formed an intimate friendship with Anna Leffler. sister of Mittag-Leffler, and a striking figure in Scandinavian letters. They had a strong influence upon each other, and of several works written in collaboration, A Struggle for Rappi 71CSS (18S7) is the most characteristic. It is a panegyric of love as the mainspring of eomplete life; and the heroine, Alice. who seeks for it in vain, is Kovalevsky herself. In one of her periods of despair she caught a severe cold, hut paid no attention to it, and attended to her lectures al most until her death from pneumonia. February 10, 1891. Consult her autobiography (trans. New York, 1595). and Anna Leffler, Sonja Kora levsky (Stockholm. 1892).