The formation of the universe

Big bang. This is a generally accepted theory at present.

The formation of the universe

The first three minutes

The original source of the universe is a singularity, the so-called "cosmic egg", which condenses all the mass and energy of time and space and breeds everything in the future material world, including celestial bodies and life. About 654.38+0.5 billion years ago, the cosmic egg suddenly broke out in an unparalleled big explosion. The Big Bang shook time and space, the material world broke out, and the era of cosmic history began.

The newly born universe grew rapidly from scratch, and exploded to a diameter of about 1 light-year after only 10-32 seconds. At 1 s, the universe became a high-temperature furnace at 1000 billion k due to the extremely high-energy radiation generated by the Big Bang, and all substances were boiled into a pot of basic particle soup. Then a violent primitive cosmic storm began, elementary particles collided violently, and neutrons melted into protons to form helium nuclei. This process lasted about three minutes until all neutrons were exhausted. About 22% of the mass is polymerized into helium nuclei, and the rest is almost unpolymerized protons. Parts per 100,000 belong to isotopes helium 3 and deuterium, and parts per billion belong to lithium. The form of primitive nebulae.

Galactic formation

The primitive biomass of the primitive universe is mainly about 78% hydrogen and 22% helium, which was completed in the first three minutes of the history of the universe. Since then, due to the cooling of the expansion surface of the universe, such a large-scale nuclear synthesis process can no longer happen, and small-scale nuclear synthesis can only wait until the stars are produced. The space of the nascent universe is full of extremely high-energy radiation, which is surprisingly hot. Protozoan hydrogen nuclei and helium nuclei are evenly distributed in the whole space, and the attraction between them is weak, which is far from enough to overcome the huge diffusion pressure and radiation pressure, so they condense into a ball. Year after year, 300,000 years have passed, and the temperature of the universe has dropped to 4,000 K, but its uniform state remains the same; In the past100000 years, the high-energy radiation in the universe cooled into microwave background radiation, and hydrogen nuclei and pseudonuclei formed their own atoms. The attraction between atoms finally overcomes the diffusion pressure and radiation pressure, and gradually forms a region with higher material density under its action, and continues to shrink toward the center; Thus the primitive nebula was formed. /kloc-after the birth of the universe 0/0 million years ago, a huge primitive nebula composed of hydrogen filled the space. Although it is very thin, it shows that the matter in the universe is no longer in a state of uniform distribution, which indicates a bright future of the universe.

Star formation

Primitive nebulae continue to gather towards the center under the action of gravity, and begin to rotate due to the tidal action between nebulae, gradually forming a lenticular shape. The contraction of the nebula makes the gravity increase, which accelerates the rotation, which leads to the instability of the edge of the nebula, which splits into two spiral arms. Local condensation occurs on the spiral arm, and each clot has a suitable volume, which can form stars in the narrow range we see. The above process continued, and the entire nebula eventually evolved into a galaxy. Galaxies in the universe were first formed about a billion years after the Big Bang. Through the Hubble Space Telescope, it can be found in other galaxies that are forming in the distant space outside our galaxy, which is exactly what happened when these galaxies formed billions of years ago. At present, the total number of galaxies observed by astronomical telescopes must be counted at 654.38+0 billion, and our galaxy is just an ordinary member. These galaxies are huge star clusters, which are extremely far away from us, so they are called "island universes". A dozen or dozens of galaxies are held together by gravity to form a cluster of galaxies; With the expansion of the universe, clusters of galaxies are moving away from each other.

The end of the universe

What is the future fate of the universe? Scientists, philosophers and theologians all put forward their own views. At present, a widely accepted view is that the universe, as a whole of the material world, also abides by the material itself and laws; According to the second law of thermodynamics, this conclusion is really unacceptable: the universe will die in the distant future-eternal death.

Imagine that in the very distant future, all the stars will go out because of lack of fuel, and the universe will be dark. In this dark and vast space, there are many black holes with rotation, discrete neutron stars and black dwarf, and some celestial bodies with stars. They fought a war under the influence of gravity. The end of the war was the disintegration of galaxies, and most celestial bodies were thrown into the intergalactic space by gravity slingshots, roaming in the expanding space forever; The black hole in the center of the galaxy won a partial victory in the merger war, devouring a few percent of celestial bodies and forming a bigger black hole. The duration of this war is beyond imagination, about one billion times the age of the universe today.

In another long time beyond imagination, when the cosmic background radiation drops to a low enough level due to expansion, all black holes will eventually disappear in a burst of rapid radiation, drawing a series of fleeting flashes in the eternal night of the universe; Other celestial bodies will decay and gradually evaporate in this long and long time until they disappear completely and become positrons or other particles; The universe has become an incredibly thin soup, which contains photons, neutrinos and a decreasing number of electrons and positrons. The glory that the universe once had, including the twinkling stars and countless miracles created by intelligent life, disappeared in this desolate and empty universe, leaving no memory, only time passed endlessly and space expanded endlessly. ...