The universe is a material world. Before human beings walked out of the earth, the earth we saw from a macro perspective was full of various materials, such as the earth, mountains, sea and other macroscopically visible things, all of which were made of material.
As humans entered the age of technology and invented the microscope, we saw the microscopic world behind the macroscopic world. In the macroscopic world, in the space where we can’t see anything, there are also a large number of microscopic particles under the microscope. They are also matter. .
After we walked out of the earth and saw the vast universe, our cognition has also been greatly improved. In the eyes of many people, the universe is a vacuum, and the distance between celestial bodies is also very large, with an average of more than a few light-years. There should be no matter in the open area between celestial bodies. But in fact, there is no absolute vacuum in the universe. There are still some microscopic particles in the vacuum where we think there is no matter, but we can’t see it with our naked eyes.
Matter constitutes everything in this world and constitutes the entire universe. According to scientific research, the total mass of matter on the earth has reached 600 billion billion kilograms, while the total mass of the solar system where the earth is located has reached 200 trillion billion kilograms. The total mass of the Milky Way galaxy is one trillion times the mass of the sun, and the Milky Way galaxy is just a particle of dust in the observable universe.
It can be seen that the total mass of the universe is a number that we cannot imagine. Many people here have to ask, how did these huge matter in the universe come from? In fact, their origins are closely related to stars. The star is equivalent to the refinement and processing plant of the elements of the universe, and it appeared shortly after the birth of the universe.
The nuclear fusion inside the star can fuse the hydrogen element into helium element, and the helium element undergoes further nuclear fusion to produce heavier oxygen element and other elements. We all know that there are 118 elements in the periodic table, which are only discovered by humans, and there may be some unknown elements in the universe that we have not discovered.
Are so many elements transformed by stars through nuclear fusion? Of course not. The nuclear fusion of stars can only convert the hydrogen element to the iron element, and the later heavier elements require other methods, such as supernova explosions and neutron star collisions at the end of the star.
Regardless of whether it is a supernova explosion or a neutron star collision, their origin is related to stars. Supernova explosions will occur at the end of star life, and neutron stars will be formed after supernova explosions of intermediate-mass stars. This shows how important stars are to the evolution of the universe. Without them, there would be nothing in the universe today.
Now that we know the origin of more than 90 kinds of heavy elements in the universe, where did the first hydrogen and helium in the universe come from? Is it really something out of nothing? First of all, we must understand that from a scientific point of view, there is no such thing as out of nothing. The first hydrogen and helium in the universe must have their sources, and they appeared following the Big Bang.
According to the Big Bang theory, at first there was no matter in the universe, and even space did not exist. 13.8 billion years ago, the universe was a space-time singularity. Later, this space-time singularity had a big bang. A space-time singularity can unfold in the form of a big bang, indicating that a huge pure energy is pushing it.
This energy caused the space created by the space-time singularity to expand rapidly after the Big Bang. According to the research of scientists, the universe has briefly experienced geometric exponential growth. In a short period of time, the space of the universe has expanded to a very large size. With the rapid expansion and expansion, this huge energy can quickly disperse and reach all corners of the universe.
With the rapid expansion of the universe, the temperature is gradually decreasing, and 10^-33 seconds after the birth of the universe, the inflation of the universe ends and pure energy begins to transform into various elementary particles. Some friends may ask: How can energy be transformed into elementary particles? In fact, Einstein’s mass-energy equation has already told us the answer to this question.
Einstein used the mass-energy equation to tell us that mass and energy are equivalent in a sense, and there is no essential difference between them. They are two manifestations of matter. After the temperature rises to a certain level, matter will exist in the form of energy, when the temperature drops to a certain level, matter will exist in the form of mass, so they can be transformed into each other.
The space-time singularity accumulates a huge amount of energy. When it has a big bang, the energy level is very high. Under this temperature, mass can only exist in the form of energy. However, with the explosion of the universe, the space exhibits geometric exponential expansion, and the temperature of the universe is also continuously falling.
After the temperature drops, the mass cannot maintain the form of pure energy and can only be transformed into elementary particles. Of course, hydrogen and helium are not directly converted from pure energy, but from the initial positive matter particles 100 microseconds after the birth of the universe, quarks gather to form protons and neutrons, and the proton is the hydrogen nucleus. A few minutes after the big bang, protons and neutrons combined to form a helium nucleus, with helium element.
According to the ratio of protons and neutrons, it can be inferred that the mass ratio of hydrogen and helium originally produced in the universe is 3:1. This is the origin of the original hydrogen and helium in the universe. They are not made out of nothing. Seeing this, some people may say that energy can be transformed into matter, what a magical ability this is. If the temperature can be reached, can humans create matter?
The mass-energy equation does tell us that energy and matter can be transformed into each other, but it is very difficult to achieve this transformation condition, and the required temperature has only appeared at the moment of the Big Bang. Therefore, you cannot realize the transformation of energy into matter in reality.
Of course, the power of science is infinite. As long as mankind develops technology to the ultimate point, it may be possible to create a temperature space that can transform matter into energy. If we do it in the future, does that mean that humans can also create a universe? If so, then we will have to think about the origin of this universe. Could it also be created by an advanced civilization outside the universe?