Thomas Young (1773-1829), a British doctor and physicist, is one of the founders of the light fluctuation theory.

Thomas Young is not only a world-famous physicist, but also involves a wide range of fields, including mechanics, mathematics, optics, acoustics, linguistics, zoology, archaeology and so on. He was interested in and loved art, played almost all musical instruments at that time, made astronomical instruments and studied the insurance economy. Thomas Young is good at riding a horse. He can juggle and walk a tightrope.

Chinese name: Thomas Young.

Thomas Young.

Nationality: UK

Nationality: England

Place of birth: Somerset, England

Date of birth: 1773-06- 13

Date of death: 1829-05- 10

Occupation: British physicist, general scientist

Graduate school: Cambridge University

Faith: Quaker

Main achievements: wave theory of light and tide theory.

Representative works: natural philosophy and mechanical technology courses, lectures on natural philosophy.

Character experience

Thomas Young was born into a wealthy Quaker family in Milverton, Somerset, England. He is the oldest of 10 children. He received a good education from an early age and showed his talents with great fanfare from an early age. He is a child prodigy to the core.

Yang began to learn to read when he was two years old, and showed great interest in books. At the age of 4, he can recite excellent works of English poets and Latin poems; When I was less than 6 years old, I had read the Bible from beginning to end twice and learned to make sentences in Latin. At the age of 9, I mastered lathe technology and could make some physical instruments by myself. A few years later, he learned calculus and made a microscope and telescope. Before 14 years old, he had mastered many languages of 10, including Greek, Italian and French. He can not only read skillfully, but also take notes in these languages. Later, he expanded his research scope to oriental languages-Hebrew, Persian and Arabic; He not only read a lot of classical books, but also finished Newton's Mathematical Principles of Natural Philosophy, lavoisier's Outline of Chemistry and other scientific works in middle school, and his intelligence was superior. At the age of 26, Yang discovered the famous Rosetta Stone. There are three kinds of characters engraved on the stone tablet: ancient Egyptian hieroglyphs, ancient Egyptian popular characters and Greek. Champollion, a Frenchman, was the first to explain these hieroglyphs, but Yang was the first to translate the inscriptions into books and publish them.

When Yang grew up, he was influenced by his uncle in his career choice (his uncle died a few years after becoming a doctor, leaving Yang with a huge legacy, including houses, books, art collections and 654.38 million pounds in cash, which made him completely independent economically and able to use all his talents where he needed them).

/kloc-At the age of 0/9, Yang came to London to study medicine. Like all European students at that time, he tried his best to enter the upper class, often visiting politician Burke, painter Reynolds and some members of the aristocratic society. 1794, Yang 2 1 year. Because of his research on the mechanism of eye regulation, he became a member of the Royal Society. 1795 came to the University of G? ttingen, Germany to study medicine, and received his doctorate one year later.

His research on medicine continued until 1797. At Emanuel College in Cambridge, his classmates called him "strange Yang Man", and he could still hear the voice of awe beyond ridicule. By the time he 1799 finished his studies, he had read some famous mathematicians' works on vibrating strings, conducted in-depth research and put forward some of his own theories, but later he found that his own theories had been put forward by others. This is the first time that Yang has shown his talents in the field of theoretical research. From 1800, he began to practice medicine in London and devoted himself to scientific research. 180 1 year, he is a professor of natural philosophy at the Royal College. Later, he served as secretary of the Royal Society.

It is worth mentioning that although his parents sent him to many famous schools, Yang still regards self-study as the most important means of learning.

Yang loves physics. Besides practicing medicine, he also spends a lot of time studying physics.

Newton once proposed in his Optical Paper that light is composed of particles. In the next hundred years, people's understanding of optics almost stagnated until the birth of Thomas Young, who became a key to uncover the truth of optics and pointed out the direction for later researchers.

Yang loves musical instruments and can play almost all the instruments at that time. This talent is inseparable from his in-depth study of sound vibration. Can light be waves like sound waves? Yang made the famous Young's double-slit interference experiment, which laid the foundation for the fluctuation theory of light.

This famous experiment has now entered the middle school physics textbook: let a beam of light pass through a small pinhole S0, and then pass through two small pinholes S 1 and S2 to become two beams of light. These two beams of light come from the same light source, so they are coherent. The results show that the light-dark interferogram can be seen on the screen. Later, a double-slit experiment was carried out with slits instead of pinholes, and brighter interference fringes were obtained.

However, this theory didn't get the attention it deserved at that time, and it was also ridiculed by the government as "absurd" and "illogical". This most important research achievement in the field of physical optics since Newton has been suppressed by conservative public opinion lacking scientific discussion atmosphere for nearly 20 years.

Yang didn't bow to authority, so he wrote a paper, but the paper had nowhere to be published and had to be printed into a booklet. It is said that "only one copy was printed" after publication. Yang fought back bravely in the paper: "Although I admire Newton's name, I don't think he is always correct. I am sorry to see that he will make mistakes, and his authority may even hinder the progress of science sometimes. "

Yang's research in the field of physical optics is of pioneering significance. He was the first to measure the wavelengths of seven kinds of light, and the first established the principle of three primary colors: he pointed out that all colors can be obtained from the three primary colors of red, green and blue. Yang is also good at elasticity. In order to commemorate his contribution, later generations called the longitudinal elastic modulus Young's modulus.

At the age of 18 14 and 4 1 year, Yang became interested in hieroglyphics. When Napoleon went on an expedition to Egypt, he found the famous Rosetta stone engraved in two languages, which was later transported to London. The Rosetta Monument is said to have been built in the 2nd century BC when the Egyptian king offered sacrifices. There are 65,438+04 lines of hieroglyphics in the upper part, 32 lines of secular characters in the middle part and 54 lines of ancient Greek characters in the lower part. It has been studied before, but there is no breakthrough. Yang deciphered 86 lines in the middle and lower part, deciphered 9 names of members of the 13 royal family, and found the reading method of pictographic symbols according to the directions of birds and animals in the inscription.

This happened around 18 16. At that time, Yang lost confidence in optical research, and some even laughed at him as a madman, which made him very depressed. He used his rich linguistic knowledge to turn to archaeological research. Because of Yang's achievement, a new discipline of studying ancient Egyptian civilization was born. When Thomas Young died in 1829, people engraved the words on his tombstone: "He was the first to decipher the ancient Egyptian hieroglyphics that no one could decipher for thousands of years".

In his later years, Yang has become a world-renowned scholar, and has written more than 40 biographies of scientists and countless entries for the Encyclopedia Britannica, covering everything. At the same time, he also worked as a statistical inspector in an important insurance company, and was appointed as the host of the nautical astronomical calendar, doing a lot of work to improve practical astronomy and navigational AIDS.

Besides science, he is immersed in art and leads a colorful life: music, art and even acrobatics have been nourishing his life. His vigorous life ended on 1829 at the age of 56. He was writing an Egyptian dictionary before he died.

Main work

1, natural philosophy and mechanical technology course (1807)

2. Introduction of medical literature and classification of actual diseases (18 13)

3. Explanation of Laplace's celestial mechanics principle (182 1 year)

4. Acousto-optic Experiment and Exploration Outline (180 1 year)

5. Observation of visual process (1973)

6. Lecture on Natural Philosophy (1807)

Main contribution

Young's double-slit experiment

Thomas Young's greatest contribution to physics is the study of optics, especially the wave nature of light. 180 1 year, he conducted the famous Young's double-slit experiment, discovered the interference property of light, and proved that light exists in the form of waves, not particles as Newton imagined. This experiment was rated as one of the "most beautiful experiments in physics". At the beginning of the 20th century, physicists combined the results of Yang's double-slit experiment with Einstein's light quantum hypothesis, and put forward the wave-particle duality of light, which was later extended to all particles by De Broglie using quantum mechanics.

Young's modulus

Young's modulus is a term in material mechanics, which is used to measure the elasticity of objects. In 1807, Yang defined "elastic modulus of materials" as "the ratio of the pressure generated at the bottom of a cylinder of the same material to the weight that causes a certain degree of compression is equal to the ratio of the length of the material to the length shortening". If the cylinder here is understood as the weight of the cylinder per unit bottom area, then this definition is the universal Young's modulus of elasticity. Yang realized that shear is a kind of elastic deformation, which is called deformation, and noticed that the resistance of materials to shear is different from that of materials to tension or compression, but he did not introduce different stiffness modulus to express the resistance of materials to shear. Young's modulus was once praised as a new era in the history of science by the British mechanic A.E.H Love.

Vision and color

Thomas Young was once considered as the founder of physiological optics. In 1793, he proposed that the lens in the human eye will automatically adjust to the distance from the object it sees. He was also the first doctor to study astigmatism (180 1 year). Later, he proposed that color vision depends on three different nerves in the eyes, which feel red, green and purple respectively. Later Helmholtz improved this theory. This theory was proved by experiments in 1959. He put forward the color theory, that is, the principle of three primary colors. He thinks that all colors can be mixed with different proportions of red, green and blue. This principle has become the basis of modern color theory.

Medical science

Thomas Young's contributions to hemodynamics include: a report entitled "Function of Heart and Blood Vessels" published at the Royal Medical College (1808); Introduction to medical literature (1813); Pathology practice (1813); History and treatment of debilitating diseases (18 15) and so on.

linguistics

Thomas Young compared 400 languages and put forward the Indo-European language family in 18 13. This language family was first proposed by Dutch linguists Van Beukes and Bern 165 years ago (1647).

Egyptian hieroglyphics

Thomas Young was also one of the first Europeans to try to translate Egyptian hieroglyphics (the other two were De Sassi in French and Akbrad in Swedish).

other

Yang is a pioneer in analyzing the impact effect of elastomer. He pointed out that when the rod is subjected to axial impact and the beam is subjected to lateral impact, quantitative results can be obtained from energy analysis. Yang also studied the torsion, eccentric tension and compression of materials. In engineering, he put forward the strength analysis method of general shells in shipbuilding. As a doctor, Yang studied the blood flow, and was the first to derive the formula of pulse wave propagation velocity by mechanical method (1808).

Yang's achievements in optics and mechanics can be found in his book Lecture on Natural Philosophy and Mechanical Technology (1807).

Personal life

1. Dare to challenge authority

180 1 year, Thomas Young wrote in his book Outline of Experiments and Exploration of Sound and Light: "Although I admire Newton's name, I don't think he is always correct. I am sorry to see that he will make mistakes, and his authority may even hinder the progress of science sometimes. " Out of his keen thinking on scientific truth, he dared to express his opinions and challenge authority.

2. An encyclopedic scholar

Thomas Young has a wide range of interests and profound knowledge. Besides being famous as a physicist, he has also made achievements in many other fields.

He has read widely since he was a child, and he is not bad at classical books, literary books and scientific works. He can read a few lines at a glance. He was proficient in painting and music and mastered almost all the musical instruments at that time. He has studied mechanics, mathematics, optics, acoustics, physiological optics, linguistics, zoology, Egyptology and so on all his life, so he can be said to be an encyclopedic scholar.

Winning record

1 and 1794 were elected members of the royal society.

2. Elected as an academician of the French Academy of Sciences.