What is the origin of the universe?

For a long time, nebula theory dominated the theory of the origin of the universe. Now, it has been accepted by many people that the universe originated from the Big Bang, although people still don't know who lit the fuse that triggered the Big Bang. In the popular science film about the origin of the earth's universe broadcast by CCTV, the imaginary scene of BIGBANG is also vividly displayed. As a systematic theory to explain the origin of the universe, the Big Bang model has been widely accepted by astronomers, quoted by many media and written into textbooks.

It is said that the Big Bang theory was put forward by the Bishop of the Belgian Catholic Church, Guiol Gith Lemaistre, who likes physics. 1927, Guiol gith Lemaistre received a doctorate in philosophy from the Massachusetts Institute of Technology. Also in this year, according to Einstein's theory of relativity, Lemaistre proposed that the universe is uniformly expanding in any direction and anywhere. He believes that the universe is formed by the explosion of primitive matter containing all matter. Edwin Hubble's subsequent discovery of the expansion of the universe supported the Big Bang model. Hubble found that distant galaxies are rapidly leaving from all directions, rather than approaching the earth. This is the expansion of the universe discovered by Hubble in 1929, which prompted many scientists to think that the initial explosion could generate enough energy to cause the expansion of the universe.

Around 1940, astrophysicists began to study the initial explosion that triggered the big bang. Their theory is that the temperature of the plasma generated after BIGBANG should be higher than that of any existing star, and with the passage of time, it should slowly cool down and gradually move closer to the so-called "absolute zero", just like a pile of extinguished bonfires, and there is still residual temperature in the ashes. This is the so-called "microwave background radiation" theory, which means that the farther away from us, the higher the background temperature of the universe should be. However, the theory of "microwave background radiation" was not paid attention to by astronomers and physicists at that time, because in their view, the so-called Big Bang theory was just a joke, and in their view, it was impossible to measure or confirm the existence of microwave background radiation.

1965, things took an unexpected turn: scientists at Bell Laboratories announced that they had stumbled upon the continuous hiss of microwave background radiation while developing receivers for communication satellites. The Big Bang theory was questioned before 1965 because it was not verified, but now there is finally evidence that the residual radiation that BIGBANG may leave does exist. As a result, many famous scientists devoted themselves to BIGBANG's research team and found more evidence to support the Big Bang theory.

Because microwave background radiation is particularly important in the Big Bang theory, the National Aeronautics and Space Administration (NASA) even launched a microwave satellite at 1989 to measure this "cosmic background". The Microwave Background Radiation Detector (COBE) hopes to detect the microwave background radiation of 500,000 years after the Big Bang. At this point, the universe is cool enough for matter to form and emit light. COBE lived up to astronomers' expectations. Satellite detection data confirmed that the cosmic background radiation is indeed isotropic, and the temperature is close to 3 Kelvin (2.276 Kelvin). Astronomers also found that the accuracy of matching this radiation with the expected blackbody spectrum was surprising.

By 1992, an all-sky star map based on the data collected by COBE also confirmed another prediction: after the Big Bang, the substances formed by cooling gas will eventually gather together to form galaxies containing stars, which is also in line with the theory that microscopic quantum fluctuations in the early universe will inevitably disturb the uniform distribution of substances. For example, the universe seems to be a pot of stumbling broth-as we all know, when starch is poured into the pot without complete mixing, it is inevitable that lumps will appear, even if they are few, they will stand out. American physicist hans bethe pointed out in 1939 that heavy elements can be synthesized in stars. These elements are the components that make up stars and our human bodies, but they only account for 2% of the mass of the whole universe, and the rest are composed of 75% hydrogen, 23% helium and a small amount of lithium. These light elements were formed during the Big Bang. Heavy elements that "melt" in the "melting pot" of stars will eventually be thrown into space, and these heavy elements will become the "seeds" of solid matter condensation in the universe. The oldest stars keep very few light elements, because the older the stars, the longer they throw matter into space. The distribution of elements in the universe is called "cosmic element abundance", which accords with the big bang theory.

So far, it seems that the Big Bang theory is correct. After a lot of verification by scientists, this theory is considered to be valid. However, while accepting the big bang theory, most astronomers are aware of some doubts in the big bang theory, and some doubts even endanger the correctness of the big bang theory itself.

For example, Fred Hoyle is the main opponent of the Big Bang Theory. From 65438 to 0948, Fred Hoyle, Herman Band-Aid and Thomas Gold put forward a theory called "steady state". According to the theory of "steady-state" universe formation, the actual age of the universe is much older than we know, and it seems that the universe has always existed and will always exist. One galaxy after another will be born, grow and die, and new galaxies will be born from the ashes of dead galaxies, but the total mass of the universe will remain conservative. In this way, even the oldest galaxy that people can observe on earth is actually quite young on a larger scale.

However, Huo Yier's theory itself is not perfect. For example, he used a modified cosmological constant. Cosmic constant is a mathematical factor introduced by Einstein in his theory of relativity to prove the invariance of the universe. As early as 1929, Edwin Hubble discovered in his research that the spectrum of distant galaxies moved to the red end, which was called "red shift". He therefore concluded that with the expansion of the universe, galaxies separated from each other at a rapid rate. This shows that the universe is not constant and Einstein's cosmological constant is not necessary. Even Einstein regarded the introduction of cosmological constants as the biggest mistake he made in his life.

Cosmic constants are opposed by most physicists. After the discovery of microwave background radiation in 1965, it seems that Huo Yier's steady-state theory should be eliminated. But Huo Yier is not reconciled. He thinks there may be some minor problems in his theory, but the big bang theory is even more problematic. In fact, the big bang theory has also encountered new problems. Physicists are familiar with the problem that the early universe did not conform to the universal laws of physics. At least 500 thousand years after the big bang, the universe has not cooled enough to form matter and release light. Big bang theorists must assume that the initial universe is a singularity. Huo Yier and his followers condemned this view. They sneered: "You might as well doubt the correctness of the Big Bang theory rather than find something to screw it up."

From 65438 to 0990, Huo Yier began to make some new progress. One of his followers, holden Alp, an American astronomer at Max Planck Institute of Technology in Germany, pointed out that there are many redshift observations that are not consistent with their actual distances. This is a very serious problem. If the redshift is not a reliable indicator of the expansion speed of the universe, it will bring a fatal blow to the Big Bang theory. Maybe galaxies won't separate so quickly, so there is no need to use the big bang to explain the forces driving their movement. Alp further stated in 199 1: "This revealed a great secret, that is, these decisive celestial bodies were deliberately ignored and the debate was suppressed."

There is an unverifiable but most important new viewpoint about the Big Bang theory, which was put forward by Allen Gus in 198 1. He believes that in the first "one second" after BIGBANG, the universe suddenly expanded, much faster than the expansion speed of the universe now, just like something the size of a needle tip suddenly expanded into the size of an orange or a softball in a very short time. This is mathematically incredible: the added volume is 10 to the 50th power, which means that 1 is followed by 50 zeros. After experiencing this sudden surge, the universe slowed down and began to expand at a speed that now seems normal.

The emergence of inflation theory dispelled the dark clouds above the big bang theory, so it became popular. It solves many problems, one of which is about the flat universe. Physicists believe that the universe is either open, that is, it will expand forever along a certain surface; Either it is closed, that is, gravity will eventually pull it back, perhaps ending in an original atom that produced the big bang. But there is no observable information to prove whether the universe is open or closed. There are indications that the actual situation seems to keep a balance between these two possibilities. This situation is described as a flat universe, because the average curvature of space-time is zero and it is a flat orbit.

Allen Goose's inflation theory points out: Don't always describe inflation as a needle tip turning into an orange, but imagine inflation as blowing a balloon. The bigger the balloon expands, the flatter its surface. Because the universe suddenly skyrocketed, it actually caused a flattening effect. According to his theoretical prediction, this rapid expansion will inevitably produce many separate "bubbles". The walls of these "bubbles" should be obvious, but they are not. Finally, Gus published his theory, hoping that other cosmologists all over the world should be interested enough to solve this problem. Russian physicist andrei linde was the first to give the answer, and then others got the answer. He mathematically proved that "bubbles" (later renamed "regions") can be generated independently. What's more, the known universe only occupies a "region" of one billion or even one trillion. These "bubbles" are so far apart that we can never observe them. Just like inflation theory, bubble domain theory is enthusiastically supported by most cosmologists, including Stephen Hawking. Although the bubble domain theory cannot be verified, it solves some problems that cannot be verified in the inflation theory: the inflation theory not only explains the flatness of the universe, but also overcomes some shortcomings of the Big Bang theory, including the isotropic distribution of matter in the universe-the moment of inflation is like the behavior of the cosmic agitator. For critics like holden Alp and Fred Hoyle, this is far from satisfactory. No matter how elegant mathematics is, theory is completely consistent with theory. But critics are a minority after all. Although more physicists find it difficult to accept all aspects of the Big Bang theory and the inflation theory, they are willing to challenge some small problems instead of laughing at the whole theory.

At present, the Big Bang theory has become the best theory to explain the origin of our universe. What needs to be emphasized is not to forget another "area" that is always out of our sight. The development of deep space exploration technologies such as Hubble telescope and high-speed computer technology has broadened our horizons. When quantum physics experiments go deep into the strange world of subatomic particles, people's knowledge seems to be constantly supporting the Big Bang theory. Some people, including Stephen Hawking, are optimistic that we may be approaching the understanding of the whole universe, and the era of grand unified theory may not be far away. Finally, we have to remind you that even among the supporters of the Big Bang Theory, there are many skeptics. Our understanding of the universe is just the beginning, and perhaps the mystery of the formation of the universe will never be solved in the time of human existence.

So the big bang theory is called the standard theory, but it is not a truth.