James Clerk Maxwell

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James Clerk Maxwell : biography

13 June 1831 – 05 November 1879

Maxwell’s article about dynamic theory of electromagnetic field was published in 1864, and its mechanic model was replaced with “Maxwell’s equation” – a mathematical formula of field’s equation – and the field itself was firstly interpreted as a real physical system, which had a definite energy. In this article he also predicted existence not only magnetic, but also electromagnetic fields. At the same time with investigations of electromagnetism Maxwell also made several experiments, checking his results in a kinetic theory. When he constructed a device, which defined air’s viscosity, he was convinced that coefficient of internal friction actually didn’t depend on density.

In 1865 Maxwell got tired of his pedagogical activity. It wasn’t surprising – his lectures were too difficult to maintain discipline during them, and his scientific work, unlike teaching, occupied all his thoughts. The decision was taken, and the scientist moved to his native estate. Immediately after removal he was injured during horse-riding and was ill with erysipelatous inflammation. When у recovered, he started actively to take care of the household, rebuilding and widening his estate. But he didn’t forget about his students – he regularly went to London and Cambridge to conduct examinations. It was Maxwell who obtained imposition of applied questions and tasks on examinations. At the beginning of 1867 a doctor advised an ill wife of Maxwell to receive treatment in Italy, and they spent the whole summer in Florence and Rome. The scientist met a professor Matteucci, an Italian physicist, and practiced in foreign languages. Incidentally, Maxwell knew Latin, Italian, Greek, German and French rather well. The Maxwells returned to Britain through Germany, Holland and France.

At that year Maxwell also composed a poetry, devoted to Peter Tate. This comic ode was named “To the Main Musician, playing the nabla” and was so popular that assigned a new term “nabla” in science, which came from a name of Assyrian musical instrument and meant a symbol of vectorial differential operator. It should be noticed that his friend Tate, who presented with Thompson the second principle of thermodynamics JCM = dp/dt, also invented Maxwell’s pen name, with which the scientist signed his poetry and letters. As the left part of the formula was equal to Maxwell’s initials, he decided to use the right as his sign.

In 1868 Maxwell was offered a post of a rector in the Saint Andrews University, but the scientist refused because he didn’t want to change his solitary way of life in his home. Only three years later after long hesitations he headed a just opened physical laboratory in Cambridge, and accordingly, he became a professor of experimental physics. When Maxwell agreed to take this post, he immediately started to organize building works and equip the laboratory (firstly with his own devices). He started to deliver lectures about electricity, heat and magnetism in Cambridge.

In 1871 Maxwell’s textbook “Theory of Heat” was published; afterwards it was republished several times. The last chapters of the book contain the main postulates of molecular-kinetic theory and Maxwell’s statistic ideas. He also refuted the second principle of thermodynamics, which was formulated by Clausius and Thompson. This formula predicted “the thermal death of the Universe” – merely mechanic point of view. Maxwell asserted statistic character of a much talked-about “the second principle”, which according to his point of view could be broken with separate molecules, staying correct in occasions of big totalities. This statement was illustrated with a paradox, which was called “Maxwell’s demon”. The paradox consisted in an ability of “the demon” (managing system) to decrease entropy of this system, not spending work. This paradox was solved in the 20th century, indicating a role of a managing element of fluctuation and proving that when “demon” gets information about molecules, it increases entropy, and that’s why there is no violation of the second principle of thermodynamics.