Archives of Paper’s Abstracts
Dějiny věd a techniky, No. 1, Vol. XXXVII (2004)
/04:1:1/
Tomáš Martan
History of Solitons and Their Aplication in Optical Communications
(Historie solitonových vln a jejich využití v optické komunikační technice)
The paper is devoted to circumstances of the first historically documented observation of water solitary wave and to facts about investigations of the phenomenon. It finally deals with seeking any suitable mathematical description of this phenomenon. After the World War II the solitary waves were again observed in context with other physical phenomena. The history of investigations and importance of solitons was described until these days. Optical solitons are especially used for a fast transmission of information by optical fibres over large distances.
In 1834 a Scottish engineer John Scott Russell discovered a water solitary wave. Russell made a model of the canal and tried to reproduce and study the water waves of the same type. The results of his observations gave him possibility to obtain an empirical formula. Some of leading scientists expressed their opinion that the waves of constant form cannot exist, and proclaimed Russell’s conclusions based on experiments as empirical and controversial. In 1895 Diederik Johannes Korteweg and Gustav de Vries had formulated the final regular description of this wave type.
During a rather long time almost no scientific attention was paid to these waves. In the second half of the 20th century Enrico Fermi, J. R. Pasta and Stanislaw Marcin Ulam studied the final heat conductivity of solids. They observed a strange phenomenon which was conformable to Russell’s wave. Norman J. Zabusky and Martin D. Kruskal carried out numerical studies and experiments for explanation of this phenomenon. Since early 1970s there were done important analytical proposals and experiments for soliton fiber communications which are becoming at present the most important technical application of solitons.
/04:1:23/
Vítězslav Orel
Stalin and Lysenkoism—according to Documents from the Opened Archives
(Stalin a lysenkismus. Z výpovědi odtajněných archivů)
With the support of Stalin T. D. Lysenko (1998—1976) in his lecture about the situation in biological sciences in USSR in 1948 substituted “the reactionary science” genetics with teaching of heredity of the acquired characteristics, described in literature as lysenkoism. Zhores Medvedev (*?1925) was first and only naturalist in 1960s in USSR who rejected this pseudo-scientific teaching. After publishing his book about the frauds of Lysenko in USA in 1969 he was arrested and only with the support of prominent geneticist B. L. Astaurov he was allowed to emigrate to Great Britain. According to new information found in the opened archives in Moscow after 1990 Medvedev now explains that the main opponent to genetics was Stalin himself. He welcomed lamarckism for the justification of political revolution and in Lysenko found a kind of man prepared for promoting his ideological priorities. Attention is also drawn to the political climate in 1930s when prominent geneticists began to be persecuted and liquidated. At that time N. I. Bucharin was also executed, though designated by Lenin as the most influential theoretician in the Communist party.
© M. Barvík 2004