Pascal is a famous theologian. He is the founder of mathematical probability theory. Starting from the discussion of gambling opportunities, this kind of research is of great practical significance to science, philosophy and social statistics.
1623 19 June, Pascal was born in Clermont, France. Ferrand city. His father is a very talented mathematician, which provides a good family environment for Pascal's growth. Pascal is very interested in mathematics. 1640 published a paper on conic curve and put forward the basic theorem of projective geometry.
Pascal was sickly since childhood, but he was clever, clever and diligent. He lived only 39 years old, but he became a scientist, philosopher and writer. His Records of Letters and Thoughts to Outsiders is a masterpiece of French literature with rigorous and beautiful language and profound thoughts.
Pascal put forward Pascal's theorem in mathematics at the age of 16~ 17.
Girard Girard Desargues, a French mathematician, was born in 159 1. He began to study projective geometry from Apolloni's study of conic curves in ancient Greece. The second person who contributed to projective geometry was Pascal.
From the age of 13, my father often took Pascal to attend the regular meeting of Mei Sen College in France, which was the predecessor of French Academy of Sciences. Pascal could understand Mei Sen's speech and was appreciated and helped by Gillard Girard Desargues.
1640, Pascal published a paper on conic curves, which led to more than 400 inferences, put forward the basic theorem of projective geometry called mysterious hexagon by Gilad Girard Desargues, and made the most important research on conic curves since Apolloni.
This geometric theorem named after Pascal is very concise; If a hexagon is inscribed in a circle (more commonly a conic curve), every two opposite sides intersect to get three points, which are on the same straight line.
In other words, if three pairs of straight lines inscribed with a hexagon intersect, then these three intersections must be * * * straight lines.
Mathematical historians believe that this theorem alone is enough to make Pascal immortal. Indeed, Pascal was only sixteen or seventeen at this time. Descartes, a famous mathematician at that time, couldn't believe that such an important theorem came from a teenager when he saw the paper. He shook his head and said, "A teenager of 17 years old won't find this theorem!"
Pascal's work initiated the research of projective geometry, and created the preparation conditions for the birth of calculus. Leibniz, a famous German mathematician and one of the founders of calculus, said: "When I read Pascal's works, I suddenly realized a truth like an electric shock."
1642, 19-year-old Pascal also invented a gear computer that can do addition and subtraction, and obtained a patent. This is the first mechanical computer in the world.
In physics, the unit of atmospheric pressure is named "Pa" to commemorate the genius physicist Pascal.
Pascal is not only a genius in physics, but also a real genius in mathematics. Here, let's talk about his research on atmospheric pressure.
1646, French physicist Pascal was interested in the atmospheric pressure experiment of Italian physicist Torricelli and began to study atmospheric pressure. He believes that "vacuum is not impossible in nature, and nature does not avoid vacuum with such great disgust as many people think."
Pascal came up with an experiment to bring a mercury barometer to the top of the mountain. The mercury column should be lower than the bottom of the mountain. In poor health, he entrusted his cousin to take Torricelli's mercury instrument to Dom Mountain. Sure enough, at the height of 1 mile, the mercury column dropped by 3 inches. This experiment is repeated, which strongly supports Pascal's view on atmospheric pressure.
Pascal made an important discovery in liquid pressure. He found that the pressure acting in the sealed liquid can be completely transferred to any place inside the liquid and act vertically on any interface it touches. This is the famous Pascal principle, which is Pascal's law.
1647, Pascal made a wonderful experiment. He made a big barrel, which was well sealed and watertight. He made a small hole in the lid of the vat and inserted a very thin tube with a length of 13m into the hole. After doing this, he took the bucket outside and put it under the house.
Then Pascal climbed up the roof with a ladder, and the roof was already crowded with onlookers. Pascal said to everyone, "here we are going to do an experiment to see how much pressure water can produce, which is also to prove one of my findings."
After a while, the bucket was filled with water. Pascal held the kettle in his hand and said to everyone, "I'm going to fill the small tube now, because the bucket is full, so the water in the small tube will be filled higher and higher." This small pot of water in my hand is not heavy, even a child can lift it, but once it is pulled into a thin and high water column, it will have unexpected effects. "
Pascal let the water in the pot flow slowly down the thin tube. Just a moment later, before the water in the pot was finished, it exploded with a bang, the vat opened and the water gushed out. People are too surprised to speak. What a surprise! The pressure will be so great!
Pascal explained that the barrel was broken because the water in the thin tube gave the water pressure in the barrel, which was transmitted to the inner wall of the barrel in all directions by the water. Therefore, if two containers with different cross-sectional areas are connected together, for example, a thin tube is connected to a wooden barrel, and a small pressure is exerted on the small cross-section, a large pressure will be generated on the large cross-section, because the liquid transmits pressure.
Pascal also found that the hydraulic press is a lever, and the product of force and arm is constant. In a hydraulic press composed of two pistons, the bigger the piston, the smaller the height change of the liquid and the greater the force.
1648, Pascal published an important experimental report on liquid equilibrium. After his death, he published a book on liquid balance and gas pressure.