Methods in theoretical physics
One can distinguish between two main procedures for a theoretical physicist. One of them is to work from the experimental basis. For this, one must keep in close touch with the experimental physicists. One reads about all the results they obtain and tries to fit them into a comprehensive and satisfying scheme.
The other procedure is to work from the mathematical basis. One examines and criticizes the existing theory. One tries to pinpoint the faults in it and then tries to remove them. The difficulty here is to remove the faults without destroying the very great successes of the existing theory.
There are these two general procedures, but of course the distinction between them is not hard-and-fast. There are all grades of procedure between the extremes1.
Which procedure one follows depends largely on the subject of study. For a subject about which very little is known, where one is breaking quite new ground, one is pretty well forced to follow the procedure based on experiment. One must keep to the experimental basis if one is not to indulge in wild speculation that is almost certain to be wrong. One should not condemn speculation altogether. It can be entertaining and may be indirectly useful even if it does turn out to be wrong. One should always keep an open mind receptive to new ideas, so one should not completely oppose speculation, but one must take care not to get too involved in it.
With increasing knowledge of a subject when one has a great deal of support to work from, one can go over more and more towards the mathematical procedure.
Note
1. extremes – крайности
Questions
1) What is the purpose of this article?
2) What are two main procedures for a theoretical physicist?
3) What is meant by working from the experimental basis?
4) What is meant by working from the mathematical basis?
5) What does the choice of the procedure depend on?
Текст № 2
TENNIS
A great many different games are played with a ball. Tennis is one of them. A tennis ball is an air-filled rubber ball covered with flannel. It is made so that it bounces very well. The ball is hit with a racket back and forth across a net. A-tennis racket is a frame with strands1 of catgut2, silk, or nylon stretched across it. The frame is usually made of ash.
The game of tennis is very much like ping-pong. Ping-pong, in fact, is called table tennis.
To anyone who does not know the game, the score at times sounds strange. "Love" is used for "zero". If the score in a game is "15 – love", one side has 15 points and the other side nothing. A game tied at 40-40 is a "deuce" game3.
Tennis may be played by either two people or four. Games in which two people play are called "singles". "Doubles" are games with four players. Both men and women play tennis. If each team in a match is made up of a man and a woman, the match is called "mixed doubles". "Tennis" is short for "lawn tennis". At first the game was played on grass-covered courts. But now many courts are bare. Some are clay-covered, some are concrete, and some are even covered with cinders.
Tennis was invented by an English major in 1873. He called it by the peculiar name, but many liked the game. Now tennis is played all over the world.
Although outdoor tennis is a little more than 100 years old, its ancestor court tennis goes back to the Middle Ages. Kings and noblemen played court tennis indoors in special rooms built for it. Every year there are world and European championship tennis matches. The most famous tennis matches are held at Wimbledon (England). The best-known trophy is the Davis Cup4. The Davis Cup matches are also international.
In Russia tennis began to develop in the end of the 19th century. In 1903, Russian sportsmen took part in international competitions for the first time. The first championship of the Soviet Union was held in 1924. And since 1958 our sportsmen have been taking part in all international competitions.
There are officials5 at tennis tournaments. But the players themselves help with the rulings. If a player makes a mistake which the official fails to see, the player reports it. No player accepts a point unless he is sure he is entitled to it. For this reason tennis is often called a "gentleman's game".
Notes
1. a strand – нить
2. a catgut – струна
3. A game tied at 40-40 is a "deuce" game. – Если в игре соотношение очков 40-40, счет становится «ровно».
4. the Davis Cup – Кубок Дэвиса
5. officials – судейская коллегия
Questions
1. Is tennis played with a ball or without it?
2. How many people may tennis be played by?
3. Who invented tennis?
4. When was the first championship of the Soviet Union held?
5. Why is tennis often called a "gentleman's game"?
Текст № 3
RADIUM
The early alchemists1 spent most of their time trying to change common metals such as lead into gold. Many people laughed at the idea. The alchemists had no clear notion of what they were doing. They simply tried all sorts of strange "recipes" and hoped to make the change take place by magic.
Now the scientists know that the alchemists were not entirely wrong. For it is possible for certain metals to change into others. The discovery and study of radium showed that this is true. The alchemists would be unhappy, however, because radium, which is thousands of times more expensive than gold, goes through a series of changes and becomes common lead.
Radium is one of the simple substances, or elements, that scientists call radioactive. Radioactive elements change all by themselves into other elements. As they do so, they send out powerful rays. These rays can go through many substances that light cannot go through. The rays from radium, for instance, can go through flesh and be used to treat such diseases as cancer.
A common use of radium is in paint. Paint containing very tiny amounts of this element is used on the hands of clocks and watches to make them glow in the dark. Chemicals in the paint give out flushes of light when hit by rays from the radium.
Carelessly used radium can cause terrible burns. Supplies of it must be kept in special containers with thick lead walls.
Pure radium is a white metal. It is very heavy. But there is so little of it that no one has ever been bothered by its weight. Only a few pounds have been produced in the whole world.
Radium was discovered by the French scientists Pierre and Marie Curie. The story of their work is one of the really exciting chapters in the story of science.
Note
1. alchemists – алхимики
Questions
1) What did the early alchemists spend most of their time on?
2) Is radium one of the radioactive elements?
3) What is a common use of radium?
4) What can carelessly used radium cause?
5) Whom was radium discovered by?