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05.11.2021 10:55

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Спереводом! nventors and inventions (a dialogue)pete: for thousands of years people led a primitive way of life and then incomparatively short period of time a gigantic leap has been made in the scientific andtechnical progress.ann: i also thought of how much it had been done by the people to reach thepresent state of the development of the human society.pete: yes, ann. and it is necessary to say that great contribution of thedevelopment of world science had also been made by the russian scientists andinventors before the revolution.ann: right you are, pete. she does not know the names of the great russianscientists and inventors such as lomonosov, mendeleyev, sechenov, pavlov,michurin and many others? pete: i think that it's hardly possible to name a branch of science in thedevelopment of which the russian scientists have not played the greatest role. whatdo you think of it, ann? ann: i am of your opinion. lomonosov was an outstanding innovator both inthe humanities and in exact sciences. he founded the first russian university.mendeleyev’s greatest discovery was his periodic 'system of elements. popovinvented radio. sechenov and pavlov «ere the world's greatest physiologists.tsiolkovsky is the father of rocket flying. he had decided the principles of jet propelled flying machines for interplanetary communication.pete: michurin was the greatest russian scientist and selectionist. his maindoctrine of the development of biology has been expressed in his conclusion: “wecannot wait for favours from nature”cravitational wavesin 1916 albert einstein published his theory of general relativity. in one of its major aspectsthis is a theory of the nature and operation of gravitational forces with which einstein intended toreplace the classical theory devised by isaac newton in the 17th century.einstein’s theory makes a number of predictions that are radically different from those ofnewton. one of the most striking of these is that gravitational forces should be propagated in wavesin a manner similar to the way electric and magnetic forces are. these gravitational waves shouldconsist of cyclically fluctuating gravitational forces; they should carry energy from place to placeand they should cause minute fluctuations of the surfaces of objects they encounter.any accelerated body could be a source of gravitational waves, but in practice physicistslook to large astronomical bodies such as oblate stars or binary stars.the prediction was that gravitational waves would be extremely weak: for a cylinder ametre long the amount of surface disturbance would be a fraction of the diameter of an atomicnucleus.for 40 years no one seriously looked for gravitational waves, but in the late 1950’s dr.weber began to develop equipment he thought would do the job. as receivers he used aluminiumcylinders of about a ton’s weight, and developed piezoelectric sensors that can record fluctuationsin the surface of these cylinders amounting to fractions of a nuclear diameter.in 1969 dr.weber announced that his equipment had recorded gravitational waves. sincethen he has been subjected to criticism, based mainly on his statistical analysis of the data. in spiteof the waves, experiments are now in progress both in this country and the united states.most of these try to make the detectors more sensitive or to design new kinds of detectorsthat will record frequency ranges other then the one – 1.660 cycles per second (hertz– thatdr.weber has pioneered)