Every living creature on the planet is born, grows up, gets older and eventually dies. All these laws apply beyond the Earth – stars, solar system and galaxy too, will eventually die. The difference exists only in time that for us seems like an eternity by the standards of the Universe is nonsense. But what about the Universe itself? As you know, she was born after the Big Bang 13.8 billion years ago, but what happens to her now? What is the lifecycle of the Universe and why researchers distinguish five stages of development?
The five ages of the Universe
Astronomers believe that five stages of evolution are a convenient way of representing an incredibly long life of the Universe. Agree, in times when we know only 5% of the visible Universe (the other 95% is mysterious dark matter, whose existence have yet to prove), to judge its evolution is quite difficult. However, researchers are trying to understand the past and present of the Universe, combining the achievements of science and human thought of the last two centuries.
If you happen to be under clear skies in a dark location on a moonless night when you look up you will find a gorgeous space landscape. With ordinary binoculars you can see the magnificent celestial painting of stars and spots of light, which are superimposed on each other. The light from these stars reaches our planet overcoming huge cosmic distances and makes its way to our eyes through space–time. The universe is a cosmological era in which we live. It’s called star era, but there are still the other four.
To always be the latest news from the world of popular science and high technology, subscribe to our channel in the Telegram!
There are many ways to consider and discuss the past, present and future of the Universe, but one of them more than others attracted the attention of astronomers. The first book about the five ages of the Universe was published in 1999, titled “the Five ages of the Universe: inside the physics of eternity”. (last update made in 2013). The authors of the book Fred Adams and Gregory Laughlin gave the name of each of the five centuries:
- Primitive era
- Star era
- Degenerate era
- Era Of Black Holes
- A dark era
It should be noted that not all scientists are supporters of this theory. However, many astronomers find the division into five stages is a useful way to discuss such an unusually large amount of time.
Primitive era of the Universe began one second after the Big Bang. During the first, very small period of time, of space-time and the laws of physics, the researchers believe, did not exist. This strange interval called the Planck epoch, it is believed that it lasted 1044 seconds. It is important to take into account the fact that many of the assumptions about the Planck epoch, based on a hybrid of the General theory of relativity and quantum theories, called theory of quantum gravity.
In the first second after the Big Bang, inflation began – incredibly fast expansion of the Universe. After several minutes, the plasma began to cool, and the subatomic particles began to form and stick together. 20 minutes after the Big Bang – in the superhot nuclear fusion the Universe began to form atoms. The cooling proceeded rapidly, while the universe remained 75% hydrogen and 25% helium, which is similar to what is happening today in the Sun. After about 380 000 years after the Big Bang, the universe cooled down enough so began to form the first stable atoms and appeared the cosmic microwave background radiation, which astronomers call the cosmic microwave background radiation.
See also: Scientists close to understanding why the universe exists
We live in the stellar era, at this time most of the matter existing in the Universe, takes the form of stars and galaxies. The first stars in the Universe – recently we told you about her discovery was huge and ended their lives in supernova explosions, which led to the formation of many other, smaller stars. Driven by the force of gravity, they were close to each other forming galaxies.
One of the axioms of the stellar era is that the bigger the star, the faster it burns up its energy and then die, usually in just a couple of million years. Smaller stars that consume energy slower longer remain active. Scientists predict that our galaxy, the milky Way, for example, will collide and merge with the neighboring Andromeda galaxy in about 4 billion years to form a new one. By the way, our Solar system can survive this merger, but perhaps the Sun will die much sooner.
The era of degeneration
Next comes the era of degeneration (degeneration), which will start in about 1 trillion years after the Big Bang and will continue until 1 duodecillion after him. In this period the Universe will dominate all visible today the remains of stars. Actually in space spaces full of dim light sources: white dwarfs, brown dwarfs and neutron stars. These stars are much colder and emit less light. Thus, in the era of the degeneration of the universe would be devoid of light in the visible spectrum.
During this era small brown dwarfs will hold most of the available hydrogen, and the black hole would grow and grow and grow, feeding on the remains of stars. When hydrogen around is not enough, the universe will eventually become darker and colder. Then the protons that existed from the beginning of the Universe, will begin to die, dissolving matter. As a result, in the Universe basically will remain subatomic particles, Hawking radiation and black holes.
Hawking radiation , the hypothetical process of radiation the black hole of various elementary particles, mainly photons; named after British theoretical physicist Stephen Hawking.
Era of black holes
For a considerable period of time, black holes will dominate the Universe, bringing the remnants of mass and energy. However, in the end, they will evaporate, albeit very slowly.
The authors believe, as writes Big Think that when black holes finally evaporate, there will be a small flash of light, the remaining energy in the Universe. At this point the universe would be almost a history containing only low-energy, very weak sub-atomic particles and photons.
A dark era
Eventually the electrons and positrons drifting through space will encounter each other, sometimes forming the atoms positronia. These structures are unstable, however, and their constituent particles will eventually be destroyed. Further destruction of other low-energy particles will continue, albeit very slowly. But this night look at the night sky full of stars and don’t worry – they are still very long will not disappear, but our understanding of the Universe and time may change in the future.