Shulou(Shulou.com)11/24 Report--

China's "Book of Rites" said: "the gentleman is careful to start, if the difference is not a penny, the error is thousands of miles." This is a warning, and similar phenomena often occur in the field of science, such as the "butterfly effect" discovered in 1962.

Edward Norton Lorenz, an American meteorologist, is known as the father of chaos theory and the discoverer of the "butterfly effect".

Edward Norton Lorentz, who has loved science since he was a child, is most interested in weather change. He graduated from Dartmouth College in 1938, entered Harvard University in 1940 with a second major in mathematics, and served in the United States Army Air Corps as a weatherman during World War II. After earning a master's degree in science from the Massachusetts Institute of Technology in 1943, Lorenz stayed on to teach and engage in meteorological research, where the discovery of the "butterfly effect" began.

In order to study the laws of global meteorology, Lorenz proposed a simplified mathematical model, which is a differential equation with three variables, which is later called Lorentz equation.

According to this set of equations, he uses a computer to simulate the global weather. At the beginning, in the initial conditions of the equation, he entered a data that is only reserved to the third place after the decimal point, that is, 0.506, and obtained a meteorological prediction. In order to find more accurate results, he increased the initial data to the sixth place after the decimal point, that is, 0.506127, hoping to make the prediction more accurate. As the computer had to wait for some time, he went out for a cup of coffee. When he came back, something unexpected happened, and the new result was very different from his expectations, not only not more accurate, but beyond recognition. He re-checked the equations and data, even the computer, and everything worked fine.

Through this strange phenomenon, Lorenz made a new discovery. some problems are very sensitive to the initial data, and small changes at the beginning will have an inestimable impact on the consequences. This shows that there are both regular factors and unpredictable variables in the development of objective things. Under certain conditions, these variables will affect the overall situation. This is in line with the old Chinese saying, "if the difference is as small as an inch, it will lead to a mistake of thousands of miles."

Lorenz demonstrated this phenomenon in detail and wrote a paper entitled "deterministic aperiodic flow" on November 18, 1962, which was published in the American Journal of Meteorology on January 7, 1963.

This paper points out that in things that are neither completely cyclical nor completely random, the law of the evolution of things is very sensitive to the initial conditions, and a slight change may affect the overall change. Because the irregular weather map described by the computer at that time looked like a butterfly, Lorenz called this phenomenon the "butterfly effect". From the beginning of "Butterfly effect", with meteorology as the theme, he began to study chaotic phenomena.

Irregular weather map Lorenz delivered a speech entitled "Butterfly effect" at the 138th meeting of the American Association for the Advancement of Science on December 29, 1972. Starting from the "butterfly effect" he discovered, he put forward the concept of chaos and put forward a seemingly absurd example of chaos in a pun: a butterfly flapping its wings in Brazil can trigger a tornado in Texas. His statement is impressive, at the first moment, people will laugh at the absurdity of the matter, but carefully examined, this statement is fascinating, not only in the bold imagination, but also in its profound scientific connotation and philosophical charm.

The "Butterfly effect" of Tu Yuan pexels always reminds people that if a small mechanism is not properly guided and adjusted, it may become a "bad beginning" and eventually constitute a great harm to the whole society; similarly, if properly adjusted, correctly channelled, and then after a period of efforts, it may produce a sensational effect to stimulate social progress. There are many idioms to warn against the "butterfly effect" in China, and there are similar jingles in the West:

Lose a nail and break a horse's hoof

Broke a horse's hoof and broke a war horse.

Broke a war horse and injured a soldier

Wounded a soldier and lost a battle.

Lost a battle and lost an empire.

Between "a nail" and "the survival of the empire", just like "Brazilian butterfly" and "Texas tornado", the relationship between them seems "absurd", but in chaotic systems, they have the relationship of "butterfly effect".

Chaos involves some nonlinear phenomena, which are not completely regular, but they are not completely irregular, not absolutely periodic, nor completely non-periodic.

In real life, such as population mobility, climate change, stock market, commodity sales, market prices, star operation, biological evolution, war situation, car logistics, and even human behavior, are some non-linear phenomena. With the development of computer science, chaos has developed into a discipline with far-reaching influence and rapid development.

In the past, people always thought that according to the existing discovered laws, such as Newton's laws, the future could be predicted from the present, such as the movement of celestial bodies, the time of eclipses, etc., so they believed in the causality of things.

French scientist Pierre Laplace asserted in an article in 1795, "if there is a 'wise man', he can see all the forces that make nature work at any moment." and can determine the respective locations of all the substances that make up nature, he also has extensive knowledge and ability to analyze and process these data. He can also include the motion of the largest objects to the lightest molecules in a formula, so that for this wise man, there is nothing uncertain in the universe, and it is clear at a glance what the future and the past will be. " Later, what Laplace called the "all-knowing and omnipotent wise man" was called the Laplace demon.

Pierre Laplace's view of Laplace was questioned at that time. If it is called "Laplace demon" to foresee the future from now on, it is necessary to know the initial conditions, then how can the initial conditions be determined? So in 1812, Laplace added in his "collection of essays on probability" that the "demon" also had "infinite diligence and infinite energy to record any details of the world". What is recorded at a certain moment is the "initial conditions", with these "initial conditions", the omnipotent "demon" can accurately determine the future and the past from any moment. Laplace's statement has confused many people, causing people to think that everything in the world is certain and always maintains a causal relationship.

In fact, however, this is not the case. The discovery of chaos dealt a heavy blow to the dream of causality. In all things in nature, there is an element of non-periodicity, that is, complexity, especially when the system is chaotic, any unpredictable "disturbance" may violate causality "by thousands of miles". Nowadays, chaos is a new science to explain the nonlinear phenomena in the world, and it is a scientific achievement in the study of the "complexity" of things. it involves fields such as mathematics, physics, chemistry, biology, medicine, social sciences, economics, information science, humanities and even art.

Some people say that chaos is one of the three great sciences of the 20th century: relativity destroys Newton's absolute view of time and space; quantum mechanics reveals the uncertainty of measurement; chaos excludes Laplace's predictability. It shows that our universe is not so orderly and predictable. The ordered universe discussed in science is not directly related to the real universe. Because of its subversion, chaos theory has become another revolution in scientific thought.

Source: 365th days in the History of Science. Author: Wei Fengwen, Wu Yi, Editor: Zhang Runxin, this article comes from the official account of Wechat: ID:tupydread, author: Wei Fengwen Wu Yi, Editor: Zhang Runxin

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.