The Big Bang

About 14 billion years ago the universe did not exist. And then, for a tiny fraction of a second there was a big bang, and there was all the matter and energy of the cosmos. The Big Bang was not like fireworks; It was the rapid expansion of space itself. During the first 1036 part of a second universe increased by more than 1036 times. From a homogeneous mixture of particles and radiation subsequently emerged galaxies, clusters and superclusters of galaxies that exist in the universe today. This is how scientists imagine today the formation of the universe.

Why do scientists believe that the Big Bang was the first step in the birth of the universe?

Why do scientists believe that the Big Bang was the first step in the birth of the universe? Astronomers have three very different sequence of reasoning, which provides a solid basis for this theory. Let's look at them in more detail.

The discovery of the expansion of the universe. Probably the Big Bang proves discovery Hubble made in 1929. Hubble discovered that the universe is expanding: group of galaxies fly apart from each other. But if galaxies fly apart, so they were closer to one another. Tracing the process of expansion of the universe back in time, astronomers have come to the conclusion that the universe at one time was a incredibly hot and dense formation.

The discovery of the cosmic microwave background. In the 1940s, physicist G. Gamow realized that the Big Bang would produce powerful radiation and the remnants of this radiation may still exist.

In 1964 A. Penzias and Robert Wilson discovered this radiation. It is also called cosmic microwave background radiation. The temperature of the radiation is exactly what it should be for the calculations of astronomers (2,73 K), if cooling occurs uniformly from the moment the Big Bang.

The abundance of helium in space. Astronomers found that with respect to hydrogen, the amount of helium in the space is 24%. Moreover, the nuclear reactions inside stars are not enough in order to create so many helium. But helium is just as much in theory ought to form the Big Bang.

According to the Big Bang theory, the further evolution depends on experimentally measurable parameter - the average density of matter in the universe. If the density is not greater than a certain critical value, the universe will expand forever, but if the density exceeds the critical value, the process of expansion ever stop and start the reverse phase of compression, which returns to its original state. Recent experimental data on the average density of magnitude are not enough to make a clear choice between the two options of the future of the universe.

There are a number of questions that answer the Big Bang theory can not yet. However, the basic provisions of its proved reliable experimental data, and the current level of theoretical physics allow quite reliably describe the evolution of a system over time.