Technical College national university

"Lviv Polytechnic"

Abstract

On the topic: " Einstein's theory of relativity"

Completed: student 31KI

Martynyuk R.

Accepted:

Fedina N. D.

Lviv 2019

Content

Introduction

General theory of relativity

Prerequisites for the creation of the theory of relativity of A. Einstein

The theory of relativity of A. Einstein

The role of Einstein's theory of relativity in science

Conclusion

References

Introduction

First of all, what is the theory of relativity? It is divided into two parts, the most important of which is the special theory of relativity. This is, in general, a theory from which to learn how the world looks to people who are racing around the world at an extremely high speed. And its movement should be uniform and straight - there is no increase or decrease in speed and no deviation from the straight path. The special theory of relativity is based on a very simple idea: there is no way to know whether or not you are moving. "Is that all?" - You thought. But if you develop this idea, it turns out that the consequences of such a seemingly innocent beginning are stunning. It turns out that the world is fundamentally different from how you still have it. imagined. Consider one of the most striking statements. Suppose two twin brothers were divorced: one remained on Earth and the other went on a submarine spacecraft on a long interstellar voyage and then turned back. So, the theory of relativity states that at the meeting, the astronaut will be younger than his brother, who remained on Earth. But even when the special theory of relativity does not impress our imagination, it always modifies, and sometimes makes a radical revolution of the old theories. Some of its implications are of great practical importance for electronics and nuclear power. In general, it is necessary for a real understanding of the space and time in which we live. The other part - the general theory of relativity - begins with the fact that it throws away the constraints associated with uniform and rectilinear motion, and examines the experience of observers moving in some sense arbitrarily. From these discussions, a new theory of gravity eventually emerges, which is somewhat more accurate than Newtonian under normal conditions and probably far outstrips it in extreme conditions. It is not yet of great practical use and may never be. However, studying the general theory of relativity is one of the most entertaining pursuits of a curious person. It gives us a sense of true understanding of the properties of space and time in which we live.

General theory of relativity

Albert Einstein published a special theory of relativity in 1905, and from 1907 began thinking about the description of free fall. After extensive work in November 1915, he made a report at a meeting of the Prussian Academy of Sciences, in which he formulated an equation to determine the gravitational field, known as the Einstein equation. Einstein's equation is very difficult to solve, so Einstein used approximate solutions in his writings. But as early as 1916, Karl Schwarzschild proposed the first accurate non-trivial solution to a spherically symmetric gravitational field known as the Schwarzschild metric. The following year, Einstein applied the solution found to describe the universe, and to obtain a stationary solution that corresponded to the ideas of the time, supplemented the equation with a cosmological constant. However, through the 1920s, thanks to the work of Edwin Hubble and other astronomers, it became clear that the universe was expanding. The expansion of the universe is described by the theory of Alexander Friedman, proposed in 1922.

In 1919, Arthur Eddington, observing the sky around a solar disk during a solar eclipse, discovered a shift of vision from his usual positions, which testified to the distortion of the trajectory of light rays near massive bodies. This discovery immediately brought Einstein worldwide fame [1]. However, the general theory of relativity was fully recognized by scientists only in the 1960s, when physicists identified quasars as galaxies with black holes at the center. It has also become possible to test certain predictions of the theory, such as gravitational redshift, in terrestrial conditions.

The conceptual kernel of the general theory of relativity, from which most of its conclusions derive - the principle of equivalence, which posits that gravity and acceleration are equivalent physical phenomena, that is, there is no such physical experiment that could locally distinguish the effect on the observer of a monogeneous motion the reference system that this observer is in.

This principle explains why experimental measurements of gravitational and inertial masses prove their equivalence. This statement has become the basis of many discoveries, such as gravitational redshift, distortion of light rays near large gravitational masses (such as dawns), black holes, slowing time in the gravitational field, and the like. But the principle of equivalence does not imply the uniformity of the equations of distorted space-time, and this in particular led to the emergence of the so-called cosmological constant, which appears in some theories.

Modifications of Newton's law of universal gravitation led to the first success of the new theory: the effect of the precession (rotation) of Mercury's perihelion was explained. Many other predictions of the theory have been further confirmed by astronomical observations. However, due to the high complexity of these observations and the difficulty of achieving satisfactory measurement errors, alternative theories of gravity have emerged, such as the Brans-Dicke theory or the bimetric Rosen theory. But as yet, there is no such experimental data that may necessitate a revision of the general theory of relativity.

However, there are theoretical reasons to argue that the general theory of relativity is incomplete. It is inconsistent with quantum mechanics, which results in incorrect results at high energies. Combining these two theories is one of the fundamental problems of modern theoretical physics.