The universe is not static. This was confirmed by the studies of astronomer Edwin Hubble back in 1929, that is, almost 90 years ago. He was led to this idea by observations of the movement of galaxies. Another discovery of astrophysicists at the end of the twentieth century was the calculation of the expansion of the Universe with acceleration.
What is the name of the expansion of the Universe
Some people are surprised to hear what scientists call the expansion of the universe. Most of this name is associated with the economy, and with negative expectations.
Inflation is the process of expansion of the Universe immediately after its appearance, and with a sharp acceleration. Translated from English, "inflation" - "pump up", "inflate".
New doubts about the existence of dark energy as a factor in the inflation theory of the Universe are used by opponents of the expansion theory.
Then scientists proposed a map of black holes. The initial data differs from those obtained at a later stage:
- Sixty thousand black holes with the distance between the mostmore than eleven million light-years distant - data from four years ago.
- One hundred and eighty thousand black hole galaxies thirteen million light-years away. Data obtained by scientists, including Russian nuclear physicists, in early 2017.
This information, astrophysicists say, does not contradict the classical model of the Universe.
The rate of expansion of the Universe is a challenge for cosmologists
The rate of expansion is indeed a challenge for cosmologists and astronomers. True, cosmologists no longer argue that the expansion rate of the Universe does not have a constant parameter, the discrepancies moved to another plane - when the expansion began to accelerate. Spectrum roaming data from very distant Type 1 supernovae prove that expansion is not a sudden onset process.
Scientists believe that the universe contracted for the first five billion years.
The first consequences of the Big Bang first provoked a powerful expansion, and then a contraction began. But dark energy still influenced the growth of the universe. And with acceleration.
American scientists have begun to create a map of the size of the universe for different eras to find out when the acceleration began. By observing supernova explosions, as well as the direction of the concentration of dark matter in ancient galaxies, cosmologists have noticed acceleration features.
Why the Universe is “accelerating”
Initially, it was assumed that in the compiled map of the size of the Universe, the acceleration values were not linear, but turned into a sinusoid. It was called the "wave of the universe."
The wave of the Universe says that the acceleration did not go at a constant speed: it slowed down, then accelerated. And several times. Scientists believe that there were seven such processes in the 13.81 billion years after the Big Bang.
However, cosmologists cannot yet answer the question of what determines the acceleration-deceleration. Assumptions come down to the idea that the energy field, from which dark energy originates, is subject to the wave of the Universe. And, moving from one position to another, the Universe either expands its acceleration or slows it down.
Despite the persuasiveness of the arguments, they still remain a theory. Astrophysicists hope that information from the Planck orbiting telescope will confirm the existence of a wave in the universe.
When dark energy was found
For the first time they started talking about it in the nineties due to supernova explosions. The nature of dark energy is unknown. Although Albert Einstein singled out the cosmic constant in his theory of relativity.
In 1916, a hundred years ago, the universe was still considered unchanging. But gravity intervened: the cosmic masses would invariably slam against each other if the universe were stationary. Einstein declares gravity due to the cosmic repulsive force.
Georges Lemaitre will justify it through physics. Vacuum contains energy. Because of her hesitation leading tothe appearance of particles and their further destruction, the energy acquires a repulsive force.
When Hubble proved the expansion of the universe, Einstein called the cosmological constant nonsense.
Influence of dark energy
The universe is moving apart at a constant speed. In 1998, the world was presented with data from an analysis of type 1 supernova explosions. It has been proven that the universe is growing faster.
This happens because of an unknown substance, it was nicknamed "dark energy". It turns out that it occupies almost 70% of the space of the Universe. The essence, properties and nature of dark energy have not been studied, but its scientists are trying to find out if it existed in other galaxies.
In 2016, they calculated the exact expansion rate for the near future, but a discrepancy appeared: the Universe is expanding at a faster rate than astrophysicists had previously assumed. Among scientists, disputes broke out about the existence of dark energy and its influence on the rate of expansion of the limits of the universe.
The expansion of the Universe occurs without dark energy
The theory of the independence of the expansion of the Universe from dark energy was put forward by scientists at the beginning of 2017. They explain the expansion as a change in the structure of the Universe.
Scientists from the Universities of Budapest and Hawaii came to the conclusion that the discrepancy between the calculations and the real expansion rate is associated with a change in the properties of space. No one took into account what happens to the model of the Universe during expansion.
Doubting the existence of dark energy, scientists explain: the mostlarge concentrations of the matter of the Universe affect its expansion. In this case, the rest of the content is distributed evenly. However, the fact remains unaccounted for.
To demonstrate the validity of their assumptions, scientists proposed a model of a mini-universe. They presented it in the form of a set of bubbles and started calculating the growth parameters of each bubble at its own rate, depending on its mass.
Such a simulation of the universe has shown scientists that it can change without regard to energy. And if you "mix in" dark energy, then the model will not change, scientists say.
In general, the debate is still going on. Supporters of dark energy say that it affects the expansion of the boundaries of the universe, opponents stand their ground, arguing that the concentration of matter matters.
The rate of expansion of the Universe now
Scientists are convinced that the Universe began to grow after the Big Bang. Then, almost fourteen billion years ago, it turned out that the expansion rate of the Universe was greater than the speed of light. And it continues to grow.
The shortest history of time by Stephen Hawking and Leonard Mlodinov notes that the rate of expansion of the boundaries of the universe cannot exceed 10% per billion years.
To determine the expansion rate of the Universe, in the summer of 2016, Nobel Prize winner Adam Riess calculated the distance to pulsating Cepheids in galaxies close to each other. These data allowed us to calculate the speed. It turned out that galaxies at a distance of at least three million light years can move away at a speed of almost 73 km / s.
The result was amazing: the orbiting telescopes, the same Planck, spoke of 69 km/s. Why such a difference was recorded, scientists are unable to answer: they do not know anything about the origin of dark matter, on which the theory of the expansion of the Universe is based.
Dark radiation
Another factor in the "acceleration" of the Universe was discovered by astronomers with the help of Hubble. Dark radiation is believed to have appeared at the very beginning of the formation of the universe. Then there was more energy in it, not matter.
Dark radiation "helped" dark energy to expand the boundaries of the universe. The discrepancies in determining the acceleration rate were due to the unknown nature of this radiation, scientists say.
Further work by Hubble should make observations more accurate.
Mysterious energy could destroy the universe
Scientists have been considering such a scenario for several decades, data from the Planck space observatory say that this is far from just speculation. They were published in 2013.
"Planck" measured the "echo" of the Big Bang, which appeared at the age of the Universe about 380 thousand years, the temperature was 2,700 degrees. And the temperature changed. "Planck" also determined the "composition" of the Universe:
- almost 5% - stars, cosmic dust, cosmic gas, galaxies;
- almost 27% is the mass of dark matter;
- about 70% is dark energy.
Physicist Robert Caldwell suggested that dark energy has a power that can grow. And this energy will separate space-time. The galaxy will move away in the next twenty to fifty billion years, the scientist believes. This process will occur with the increasing expansion of the boundaries of the universe. This will tear the Milky Way away from the star, and it will also disintegrate.
Space measured out about sixty million years. The sun will become a dwarf fading star, and the planets will separate from it. Then the earth will explode. In the next thirty minutes, space will tear the atoms apart. The final will be the destruction of the structure of space-time.
Where the Milky Way "flies away"
Jerusalem astronomers are convinced that the Milky Way has reached its maximum speed, which is higher than the expansion rate of the Universe. Scientists explain this by the desire of the Milky Way to the "Great Attractor", which is considered the largest cluster of galaxies. So the Milky Way leaves the space desert.
Scientists use different methods to measure the expansion rate of the Universe, so there is no single result for this parameter.
