The theory of relativity of a. Einstein

Albert Einstein (1879-1955) - theoretical physicist, one of the founders of modern physics, Nobel Prize laureate, foreign correspondent of the Russian Academy of Sciences (1922) and foreign honorary member of the USSR Academy of Sciences (1926). Born in Germany, from 1893 he lived in Switzerland, from 1914 in Germany, emigrated to the United States in 1933. Created the private (1905) and general (1907-16) theory of relativity.

Einstein's greatest popularity came from the theory of relativity, which he first set out in 1905 in the article "On the Electro-Dynamics of Moving Bodies." Already in his youth, Einstein tried to understand what an observer would see if he rushed at the speed of light in pursuit of a beam of light. As a student, Einstein studied the work of Maxwell, was convinced of the existence of permeable ether and thought about how different fields (in particular, magnetic) affect him and how to experimentally detect motion on the ether. Now Einstein strongly rejected the concept of ether, which allowed us to consider the principle of equality of all inertial frames of reference as universal, and not just limited by the scope of mechanics. Given the inability to detect absolute motion, Einstein concluded that all inertial frames of reference were equal. He formulated two major postulates that made the hypothesis of the existence of ether unnecessary, which formed the basis of the generalized principle of relativity:

1) all laws of physics are equally applicable in any inertial report system and should not be changed in Lorentz transformations;

2) light is always propagating in free space at the same speed, regardless of the source motion.

Einstein has put forward the amazing and at first glance paradoxical postulate that the speed of light for all observers, however they move, is the same. This postulate (subject to some additional conditions) leads to the formulas previously obtained by H. Lorenz for the transformation of coordinates and time in the transition from one inertial frame of reference to another, moving with respect to the first. But Lorenz regarded these transformations as auxiliary or fictitious, not directly related to real space and time. Einstein understood the reality of these transformations, in particular the reality of the relativity of simultaneity.

Thus, the principle of relativity, established for the mechanics of Galileo, was extended to electrodynamics and other fields of physics. This led, in particular, to the establishment of an important universal relation between mass M, energy E, and momentum P: E 2 = M 2 × c 4 + P 2 × s 2 (where c is the speed of light), which can be called one of the theoretical assumptions of use. of intra-nuclear energy.

In 1905, Einstein was 26 years old, but his name had already gained wide popularity. In 1909 he was elected professor at the University of Zurich, and two years later at the German University in Prague. In 1912, Einstein returned to Zurich, where he took a chair in the Polytechnic, but in 1914 he accepted an invitation to move to work as a professor at the University of Berlin and at the same time director of the Institute of Physics. Einstein's German citizenship was restored. By this time, work on a general theory of relativity was in full swing. As a result of the joint efforts of Einstein and his former student companion M. Grossman, in 1912, an article entitled "Outline of a Generalized Theory of Relativity" appeared, and the final formulation of the theory dates from 1915. the whole history of physics. Based on the well-known fact that "heavy" and "inert" masses are equal, we managed to find a fundamentally new approach to solving the problem posed by I. Newton: what is the mechanism of transmission of gravitational interaction between bodies and what is the vector of this interaction.