This paper takes part in the series essay competition of “great science” of Recordunkown.
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 all kinds of materials, such as the earth, mountains, seas and so on.
As human beings enter the era of science and technology, after the invention of the microscope, we see the micro world behind the macro world. In the macro world, in the space where we can’t see anything, there are also a large number of micro particles under the microscope, which are also substances.
When we walk out of the earth and see the vast universe, our cognition has been greatly improved. In the eyes of many people, the universe is a vacuum, and the distance between celestial bodies is very large, with an average of more than a few light years. There should be no matter in the open space between celestial bodies. But in fact, there is no absolute vacuum in the universe. In the vacuum where we think there is no matter, there are still some microscopic particles, but we can’t see them with the naked eye.
Matter makes up everything in the world, the whole universe. According to scientific research, the total mass of the earth has reached 600 billion kilograms, while the total mass of the solar system where the earth is located has reached 20 trillion billion kilograms. The total mass of the Milky way is more than one trillion times that of the sun, and the Milky way is just a particle of dust in the observable universe.
From this, we can see that the total mass of the universe is a number that we can’t imagine. Seeing here, many people have to ask, how did these huge substances in the universe come from? In fact, their origins are closely related to stars. Stars are equivalent to the refining and processing plants of cosmic elements, which appeared shortly after the birth of the universe.
Nuclear fusion inside a star can turn hydrogen into helium, which in turn produces heavier oxygen and other elements. As we all know, there are 118 elements in the periodic table of elements, which are only discovered by human beings at present, and there may be some unknown elements in the universe that we have not found.
Are so many elements transformed from stars by nuclear fusion? Of course not. The nuclear fusion of stars can only convert hydrogen to iron, while the later heavier elements need other ways, such as supernova explosion at the end of stars, neutron star collision and so on.
Whether it’s supernova explosion or neutron star collision, their origin is related to stars. When the stars reach the end of their life, supernova explosion will occur, and after supernova explosion, neutron stars will form. This shows how important stars are to the evolution of the universe. Without them, there would be nothing in the present universe.
Now that we know the origin of more than 90 heavy elements in the universe, where did the original hydrogen and helium come from? Is it really out of thin air? First of all, we need to understand that from a scientific point of view, there is no such thing. The original hydrogen and helium in the universe must have their own sources, and they came along with the big bang.
According to the big bang theory, there was no matter in the universe at first, even space did not exist. 13.8 billion years ago, the universe was a space-time singularity. Later, the big bang happened to this space-time singularity. A space-time singularity can be expanded in the form of a big bang, which shows that there is a huge pure energy pushing it.
This energy makes the space born after the big bang of space-time singularity expand rapidly. According to the research of scientists, the universe has experienced a short period of geometric exponential growth, and in a very short period of time, the universe has expanded to a very large space. With the rapid expansion of the expansion, this huge energy can also be quickly dispersed, reaching every corner of the universe.
With the rapid expansion of the universe, the temperature is gradually decreasing. 10 ^ – 33 seconds after the birth of the universe, the inflation of the universe ends, and the pure energy begins to transform into various basic particles. Some friends may ask: how can energy be converted into elementary particles? In fact, Einstein’s mass energy equation has already told us the answer to this question.
Einstein told us with the mass energy equation that mass and energy are equivalent in a sense. They have no essential difference. They are two forms of matter. After the temperature rises to a certain degree, matter exists in the form of energy. When the temperature drops to a certain degree, matter exists in the form of mass, so they can be transformed into each other.
The space-time singularity gathers huge energy. When it explodes, the energy level is very high. At this temperature, the mass can only exist in the form of energy. However, with the rapid rise of the universe, the space is expanding exponentially, and the temperature of the universe is also decreasing.
When the temperature drops, the mass can’t be kept in 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, protons are hydrogen nuclei. Minutes after the big bang, protons and neutrons combined to form helium nuclei, with helium.
According to the proportion of protons and neutrons, we can infer that the mass ratio of hydrogen and helium produced in the universe is 3:1, which is the origin of the original hydrogen and helium in the universe. Seeing this, some people may say that energy can be transformed into matter. What a magical ability it is. If the temperature can be reached, can human beings 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 only appeared at the moment of the big bang. So, you can’t turn energy into matter in reality.
Of course, the power of science is infinite. As long as human beings develop science and technology to the end, they can create a temperature space where energy can be transformed into matter. If we do it in the future, does it mean that human beings can create a universe? If so, we will have to think about the origin of the universe. Is it also created by an advanced civilization outside the universe?