What kind of man and scientist is Pascal?

Pascal is a famous French mathematician, physicist, philosopher and essayist.

1623 was born on June 9th, 2009 in Dom clermont-ferrand, France. Pascal had no formal school education. His mother died when he was 4 years old, his father was a government official, and his two sisters were in charge of his education and training. His father is a respected mathematician. Under his careful education, Pascal was proficient in Euclidean geometry at an early age. He independently discovered the first 32 theorems of Euclid, and the order was completely correct. At the age of 12, he discovered that "the sum of the internal angles of the triangle is equal to 180 degrees", and he began to learn mathematics from his father. Pascal moved to Paris with his family at the age of 163 1. His father found Pascal promising, and when he was 16, he enjoyed taking him to the academic activities of the group of mathematicians and physicists in Paris (the predecessor of the French Academy of Sciences in Paris), which opened his eyes. At the age of 65,438+07, Pascal wrote the article "The Theory of Cone Section" with a high level of mathematics, which was the result of his study of De Salgues's classic works on integral projective geometry.

Pascal moved to Rouen with his family in 164 1. During the period from 1642 to 1644, Pascal invented the adder, which is the earliest calculator in the world and is now on display in the French Museum. He accepted religious teachings in 16 10, but he accepted religious teachings. During the period of 1653, Pascal devoted himself to the study of vacuum and hydrostatics and achieved a series of important results. He returned to Paris and lived in 1647. According to Torricelli's theory, he did a lot of experiments, and the experiment in 1647 caused a sensation in Paris. He himself said that the fundamental guiding ideology of his experiment is to oppose the traditional concept that "nature hates vacuum". From 1647 to 1648, he published papers on vacuum. 1648, Pascal conceived and carried out the experiment of measuring atmospheric pressure at different heights in the same area, and found that the atmospheric pressure increased with the decrease of height. Pascal has made new discoveries in his experiments in recent years. How many more? For example, the syringe and hydraulic press were invented and Torricelli's mercury barometer was improved. From 1649 to 165 1, Pascal and his collaborator Pierre measured the changes of atmospheric pressure at the same place in detail, becoming pioneers in weather forecasting with barometer. Pascal began to summarize him at +065 1 Essays on Liquid Balance and Air Weight was written in 1654 and officially published in 1663. Pascal then turned to theological research, and 1655 entered the theological center of Petraeus. Starting from skepticism, he thinks that perceptual and rational knowledge are unreliable, and thus draws the conclusion that faith is above everything else.

Before 1646, the Pascal family all believed in Catholicism. Because of his father's illness, he came into contact with deeper religious beliefs, which had a great influence on his later life. Pascal communicated with Fermat, a mathematician, and together they solved the problem sent by a gambler and amateur philosopher in the upper class. He can't figure out why gambling on three dice in a certain combination always loses. In the process of solving this problem, he laid the foundation of modern probability theory. He made many contributions in his short life, especially in mathematics and physics. In order to test the theories of Italian physicists Galileo and Torricelli, he made a mercury barometer and repeated atmospheric pressure experiments on the top of clermont-ferrand Mountain overlooking Paris. It paves the way for the study of hydromechanics and hydrostatics. In order to improve Torricelli's pneumatic juice in the experiment, he invented a syringe and a hydraulic press on the basis of Pascal's law. His research and work on vacuum further enhanced his reputation. He was weak from childhood and became ill because of overwork. However, it was he who called in sick from 165 1 to 10. He devoted himself to science and wrote many papers on liquid balance, the weight and density of air, arithmetic triangle and so on. The latter paper became the basis of probability theory. During the period of 1655~ 1659, he also wrote many religious works. In his later years, he was advised to publish the research results on the cycloid, so he was immersed in scientific interest again, but from 1659.

Pascal died on August 9, 662 at the age of 39. Later generations named the unit of pressure after Pascal, abbreviated as "Pa".

research field

Pascal's achievements are manifold. His contribution to mathematics and physics occupies an extremely important position in the history of science.

Pascal has a deep knowledge of mathematics. In addition to his outstanding contribution to probability theory, the most prominent is the famous Pascal theorem, which was put forward in his paper on conic curves. Pascal's theorem is an important theorem of projective geometry, that is, "the intersection line of three opposite sides of a hexagon inscribed with a conic curve".

In algebra research, he published many papers about arithmetic progression and binomial coefficient, and found the coefficient law of binomial expansion, namely the famous Pascal Triangle (called "Yang Hui Triangle" in China). Together with Fermat, he laid the foundation of probability theory and combinatorial theory and obtained a series of methods to solve the problems of probability theory. He studied the cycloid problem and obtained the general solutions of different curve areas and centers of gravity.

Research contribution

In 1 and 1639, he published an excellent mathematical paper on conic curve.

2. His philosophical masterpiece Record of Thought.

Pascal discovered the law of atmospheric pressure changing with height. He not only repeated Torricelli's experiment, but also verified his own inference: Since atmospheric pressure is produced by the weight of air, the higher the altitude, the shorter the liquid column in the glass tube should be.

4. Letters to outsiders

5. 164 1 year, Pascal invented the adder.

6. Conic curve paper

7. It is found that Pascal's law (in fluid (gas or liquid) mechanics, it refers to the pressure change of a certain part of the static fluid in a closed container, and the pressure transmitted to all parts of the fluid and the container wall without loss is equal to the acting force divided by the acting area. According to Pascal's principle, the piston in the hydraulic system is under certain pressure. The same pressure increase will occur on the other piston. If the area of the second piston is 10 times that of the first piston, the force acting on the second piston will increase to 10 times that of the first piston, while the pressures on the two pistons are still equal. The hydraulic press is an example of Pascal's principle. It has many uses, such as hydraulic braking.

Pascal also found that the pressure at any point in a static fluid is equal in all directions, that is, the pressure at that point is equal in all planes passing through it, which is also called Pascal's principle (law).

An episode about physics

There is a joke that all scientists go to heaven after death. One day, it was Einstein's turn to catch people while they were playing hide and seek. After counting 100, he found Newton standing beside him and said, "Newton, I got you."

"No, you didn't catch Newton."

"Then who are you?" Einstein asked.

"What do you see under my feet?" Newton smiled slyly.

Einstein saw that Newton's foot was a square plate with a side of one meter.

"I am standing on a square meter board, and the board is Newton/square meter, so you are not catching Newton, but Pascal."

Hearing this, Einstein called Pascal. Pascal smiled, bent down to pick up the board at Newton's foot and said to Einstein, "I'm Pascal now, right?" Then I threw the board out. "There is no square meter. Now, I am Newton. "

① If you don't know, refer to the pressure.