Hendrik Lorenz

In the history of physics, Lorentz came in as the creator of the electronic theory, in which he synthesized the ideas of field theory and atomistics.

Hendrik Anton Lorenz was born on July 15, 1853 in the Dutch city of Arnhem. For six years he went to school. In 1866, after graduating from high school as a pupil, Hendrik enrolled in the third grade of the higher civilian school, approximately corresponding to the gymnasium.

His favorite subjects were physics and mathematics, foreign languages. To study French and German, Lorenz went to church and listened to these sermons in these languages, although he did not believe in God since childhood. In 1870 he entered the University of Leiden.

With great interest, Hendrik listened to lectures of university professors, although his fate as a scientist apparently determined to a greater extent the reading of Maxwell's writings, very difficult to understand and named in connection with this "intellectual jungle." But the key to them, according to Lorentz, he helped to pick up the articles of Helmholtz, Fresnel and Faraday .

In 1871, Hendrik graduated with honors from the Master's degree, but in 1872 left the University of Leiden to prepare himself for the doctoral exams. He returns to Arnhem and begins to work as a night school teacher. He likes the work very much, and soon Lorentz becomes a good teacher.

At home, he creates a small laboratory, continuing to study intensively the works of Maxwell and Fresnel. "My admiration and respect was intertwined with love and affection; How great was the joy that I experienced when I could read Fresnel himself, "recalled Lorenz.

He becomes an ardent supporter of Maxwell's electromagnetic theory: "His" Treatise on Electricity and Magnetism "produced, perhaps, one of the most powerful impressions in my life; The interpretation of light as an electromagnetic phenomenon in its boldness has surpassed all that I have known so far. "

In 1875, Lorenz brilliantly defended his doctoral dissertation and in 1878 became a professor specially for him established the Department of Theoretical Physics (one of the first in Europe) Leiden University. In 1881 he became a member of the Royal Academy of Sciences in Amsterdam.

Already in his doctoral dissertation "On Reflection and Refraction of the Rays of Light" Lorentz tries to justify the change in the speed of light propagation in a medium by the influence of electrified particles of the body. Under the action of a light wave, charges of molecules come into vibrational motion and become sources of secondary electromagnetic waves. These waves, interfering with the primary, and cause the refraction and reflection of light. Here are already outlined those ideas that will lead to the creation of the electronic theory of light dispersion.

In the following article "On the relationship between the speed of light propagation and the density and composition of the medium", published in 1878, Lorentz derives the famous relationship between the refractive index and the density of the medium, known as the "Lorentz-Lorentz formula", since the Dane Ludwig Lorenz Hendrik Lorentz came to the same result. In this work, Lorentz develops the electromagnetic theory of light dispersion, taking into account the fact that the field of polarized particles of the medium acts on the molecular charge, in addition to the wave field.

In 1892, Lorentz delivered a great work "Maxwell's electromagnetic theory and its application to moving bodies." In this paper, the main contours of the electron theory are outlined. The world consists of matter and ether, and Lorenz calls the substance "all that can take part in electrical currents, electrical displacements and electromagnetic motions."

"All the weighty bodies consist of a multitude of positively and negatively charged particles, and electrical phenomena are generated by the displacement of these particles." Lorentz then writes out the expression for the force with which the electric field acts on a moving charge. Lorentz makes a fundamental assumption - the ether does not take part in the motion of the matter of participation (the hypothesis of a fixed ether).

This assumption is directly opposed to Hertz 's hypothesis about the ether, which is completely entrained by moving bodies. In a note of 1892 "Relative motion of the Earth and ether," the scientist describes the only way, in his opinion, to coordinate the result of the experiment with Fresnel's theory, that is, with the theory of the fixed ether. This method consists in the assumption of a reduction in the dimensions of the bodies in the direction of their motion (the Lorentz-Fitzgerald contraction).

In 1895 the fundamental work of Lorentz "The experience of the theory of electrical and optical phenomena in moving bodies" was published. In this work, Lorentz gives a systematic exposition of his electronic theory. True, the word "electron" does not yet appear in it, although an elementary amount of electricity was already named by this name.

The scientist simply speaks of positively or negatively charged particles of matter - ions and his theory, respectively, calls "ion theory." "I accept," Lorentz writes, that in all bodies there are small charged particles of electricity and that all electrical processes are based on the configuration and motion of these "ions." Lorentz points out that such a view is generally accepted for phenomena in electrolytes and that recent studies of electrical discharges show that "in the electrical conductivity of gases we are dealing with ion convection."

Another assumption of Lorentz is that the ether does not take part in the movement of these particles and, consequently, of material bodies, it is immobile. This hypothesis Lorentz raises to Fresnel. Lorentz emphasizes, however, that this is not about the absolute rest of the ether, he considers such an expression to be meaningless, but that the parts of the ether are at rest relative to each other and that all the real movements of celestial bodies are movements relative to the ether. Lorentz began to develop the ideas he set out in "Experiments on the theory of electrical and optical phenomena in moving bodies," improving and deepening his theory.

In 1899 he published an article "A Simplified Theory of Electrical and Optical Phenomena in Moving Bodies", in which he simplified the theory he had given in the "Experience".

In 1900, at the International Congress of Physicists in Paris, Lorentz made a presentation on magneto-optical phenomena. His friends were Boltzmann, Vin, Poincare, X-ray, Planck and other famous physicists. In 1902, Lorenz and his pupil Peter Zeeman became Nobel laureates. In his speech at the presentation of the Nobel Prize, Lorentz said: "... we hope that the electronic hypothesis, as it is adopted in various sections of physics, leads to a general theory that will cover many areas of physics and chemistry. It is possible that on this long journey it will completely rebuild itself. "

In 1904, he made a fundamental article "Electromagnetic phenomena in a system moving at a speed less than the speed of light." Lorentz derived formulas that relate spatial coordinates and instants of time in two different inertial systems of the report (the Lorentz transformation). The scientist succeeded in obtaining a formula for the dependence of the electron mass on velocity.

In 1912, republishing this work, he admitted in the notes that he failed to fully combine his theory with the principle of relativity. "With this circumstance," Lorentz wrote, "the helplessness of some further reasoning in this work is connected."

In 1911 in Brussels was held the First International Solvay Congress of Physicists devoted to the problem of "Radiation and Quanta". Twenty-three physicists participated in his work, Lorentz presided. "We are not left feeling that we are in a dead end; Old theories are increasingly less able to penetrate the darkness that surrounds us from all sides, "he said in his opening remarks. He sets the task for physicists to create a new mechanics: "We will be very happy if we manage to get a little closer to the future mechanics in question."

In 1912, Lorentz went to the post of extraordinary professor of the department and offered his successor, who then lived in Russia, the physicist Paul Ehrenfest. In 1913, Lorentz took up the post of director of the physical cabinet of the Taylor Museum in Harlem.

Lorenz was a member of many academies of sciences and scientific societies. In 1925 he was elected a foreign member of the USSR Academy of Sciences. In the same year, Holland celebrated the fiftieth anniversary of the scientific work of Lorentz. These were great celebrations, which, according to Academician P. Lazarev, turned into an international congress. The Dutch Academy of Sciences establishes the "Gold Medal of Lorentz". The participants of the celebrations make welcoming speeches. Lorentz's response speech was very interesting and, as always, extremely modest: "I am infinitely happy that I managed to make my modest contribution to the development of physics. Our time has passed, but we passed the baton into reliable hands. "

Lorentz was recognized as the elder of physical science, the great classic of theoretical physics and her spiritual father. In 1927, the V Solvay Congress on the problem of "Electrons, photons and quantum mechanics" was held. Like all previous ones, Lorenz was the chairman of the congress.

And on February 4, 1928, Lorentz was gone. In the Netherlands, national mourning was declared. Scientists from different countries came to the funeral of the great physicist. From the Dutch Academy of Sciences Ehrenfest spoke, from England - Rutherford, from France - Langevin, from Germany - Einstein.

"His brilliant mind showed us the way from Maxwell's theory to the achievements of modern physics. It was he who laid the cornerstones of this physics, created its methods ... The image and his works will serve for the benefit and education of many generations, "said Einstein over the ashes of Lorentz. The style of Lorentz's work "take deep and strive for complete perfection" will serve, according to Max Planck, as a model for future generations.

"His works have not ceased to be excitingly interesting ... he left behind a huge legacy - the true completion of classical physics", - estimated the contribution of Lorentz Louis de Broglie.

This was and remains so in the memory of descendants Hendrik Lorentz - this "great classic of theoretical physics."