About 13.7 billion years ago, the universe formed. We still don’t know the exact conditions under which this happens, and we don’t know if there is time before that. However, using telescope observations and particle physics models, researchers have been able to piece together a rough timeline of major events in life in the universe. Here, we take a look at the most important historical moments of the universe from its birth to its demise.
Everything starts with the Big Bang. The Big Bang is a moment in time, not a point in space. Specifically, this is the moment when time itself begins, and all subsequent moments from this moment are counted. Although the name of the Big Bang is widely known, it is not an explosion in the true sense. It is a period when the universe is very hot and dense, and the space begins to expand in all directions. Although the Big Bang model indicates that the universe is an infinitely small point with infinite density, this is only an indirect way of explanation, and we are not very clear about what happened at that time. Mathematical infinity in physical equationsIt makes no sense in, so the Big Bang is indeed the point of collapse of our current understanding of the universe.
The era of skyrocketing universe
The next action of the universe is to grow rapidly. In the first 10^-30 seconds after the Big Bang, the universe expanded exponentially, separating regions of the universe that were originally closely connected. This era known as inflation is still a hypothesis, but cosmologists like this idea because it explains why distant regions of space look so similar to each other despite being far apart. As early as 2014, a research team believed that they had discovered this kind of expansion signal in the light of the early universe.
A few milliseconds after the beginning of time, the early universe was very hot. It was at a high temperature of 4 trillion to 6 trillion degrees Celsius. At this temperature Next, elementary particles called quarks can move freely. Gluons carry a fundamental force called a strong force, and they mix with quarks and diffuse in a thick primitive liquid in the universe. Researchers have succeeded. The earth created similar conditions in the particle accelerators on the earth. But this kind of difficult-to-achieve stateThe state lasted only a fraction of a second.
A lot of changes have taken place around one thousandth of a second after the Big Bang. As the universe expands, it gradually cools, and soon the conditions are mild enough to make quarks gather into protons and neutrons. One second after the Big Bang, the density of the universe dropped enough to enable neutrinos to fly forward without hitting anything, creating the so-called cosmic neutrino background, but scientists have not yet discovered this.
In the first 3 minutes of the birth of the universe, protons and neutrons fuse together to form deuterium, helium and a small amount of elemental lithium. But once The temperature dropped and the process stopped. In the end, 380,000 years after the Big Bang, everything was cool enough that hydrogen and helium could combine with free electrons to create the first neutral atom. The photons that collided with electrons before can now Move undisturbed, creating the cosmic microwave background radiationIt is a relic of this era and was first discovered in 1965.
For a long time, nothing in the universe emits light. This period, which lasted about 100 million years, is called the dark period of the universe. Research during this period is still extremely difficult, because almost all astronomers' knowledge of the universe comes from starlight. Without the stars, it would be difficult to know what happened.
About 180 million years after the Big Bang, hydrogen and helium began to collapse into large spheres, generating hellish temperatures in their cores. These temperatures The first stars were ignited. The universe entered a period called cosmic dawn or reionization, because hot photons emitted by early stars and galaxies decomposed the neutral hydrogen atoms in interstellar space into protons and electrons. The reionization continued. It’s hard to say how long it took, because it happened too early and the signal it sent was taken by the gas and dust later.Cover up, so scientists can only say that it ended about 500 million years after the Big Bang.
Early small galaxies began to merge into larger galaxies. About 1 billion years after the Big Bang, supermassive black holes formed in their centers. Bright quasars, producing strong light signals, beacons, can be seen from 12 billion light years away.
The middle age of the universe
It continues to evolve for hundreds of millions of years. The high-density points from the primitive universe attract matter to themselves through gravity. They slowly grow into galaxy clusters and long gas and dust, forming a beautiful filament that we can see now Universe net.
The birth of the solar system
About 4.5 billion years ago, in a special galaxy, a cloud of gas collapsed into a yellow star with a ring system around it. These The halo merges into eight planets, plus various comets, asteroids, dwarf planets, and moons, forming a familiar star system. This third planet from the central star will either retain a large amount of water after this process , Or the comet later transported a lot of ice and water.
Earth and humanity
Between 3.8 billion and 3.5 billion years ago, simple microorganisms appeared. These life forms appeared and evolved into magical sea monsters and huge dinosaurs .finally,About 200,000 years ago, standing creatures appeared. They were able to marvel at our mysterious universe and discover how the entire universe was formed.