Text 5 Quantum Physics

An informed list of the most profound scientific developments of the 20* centuiy is likely to include general relativity, quantum mechanics, big bang cosmology, the unraveling of the genetic code, evolutionary biology, and perhaps a few other topics of the reader’s choice. Among these, quantum mechanics is unique because of its profoundly radical quality. Quantum mechanics forced physicists to reshape their ideas of reality, to rethink the nature of things at the deepest level, and to revise their concepts of position and speed, as well as their notions of cause and effect

Although quantum mechanics was created to describe an abstract atomic world far removed from daily experience, its impact on our daily lives could hardly be greater. The spectacular advances in chemistry, biology, and medicine - and in essentially every other science - could not have occurred without the tools that quantum mechanics made possible. Without quantum mechanics there would be no global economy to speak of, because the electronics revolution that brought us the computer age is a child of quantum mechanics. So is the photonics revolution that brought us the Information Age. The creation of quantum physics has transformed our world, bringing with it all the benefits - and the risks - of a scientific revolution.

Unlike general relativity, which grew out of a brilliant insight into the connection between gravity and geometry, or the deciphering of DNA, which unveiled a new world of biology, quantum mechanics did not spring from a single step. Rather, it was created in one of those rare concentrations of genius that occur from time to time in history. For 20 years after their introduction, quantum ideas were so confused that there was little basis for progress; then a small group of physicists created quantum mechanics in three tumultuous years.' These scientists were troubled by what they were doing and in some cases distressed by what they

had done. In his seminal paper on thermal radiation, Planck hypothesized that the total energy of a vibrating system cannot be changed continuously. Instead, the energy must jump from one value to another in discrete steps, or quanta of energy. The idea of energy quanta was so radical that Planck let it lay fallow. Then, Einstein, in his wonder year of 1905, recognized the implications of quantization for light. Even then the concept was so bizarre that there was little basis for progress. Twenty more years and a fresh generation of physicists were required to create modem quantum theory.

To understand the revolutionary impact of quantum physics one needs only look at prequantum physics. From 1890 to 1900, physics journals were filled with papers on atomic spectra and essentially every other measurable property of matter, such as viscosity, elasticity, electrical and thermal conductivity, coefficients of expansion, indices of refraction, and thermoelastic coefficients.

What is most striking to the contemporary eye, however, is that the descriptions of the properties of matter were essentially empirical. Thousands of pages of spectral data listed precise values for the wavelengths of the elements, but nobody knew why spectral lines occurred, much less what information they conveyed. Thermal and electrical conductivities were interpreted by suggestive models that fitted roughly half of the facts. There were numerous empirical laws, but they were not satisfying. For instance, the Dulong-Petit law established a simple relation between specific heat and the atomic weight of a material. Much of the time it worked; sometimes it didn’t. The masses of equal volumes of gas were in the ratios of integers - mostly. The Periodic Table, which provided a key organizing principle for the science of chemistry, had absolutely no theoretical basis.

Among the greatest achievements of the revolution is this: Quantum mechanics has provided a quantitative theory of matter. We now understand essentially every detail of atomic structure; the Periodic Table has a simple and natural explanation; and spectral data fit into an elegant theoretical framework. Quantum theory permits the quantitative understanding of molecules, of solids and liquids, and of conductors and semiconductors. It explains bizarre phenomena such as superconductivity and super fluidity, and exotic forms of matter such as the stuff of neutron stars and Bose-Einstein condensates, in which all the atoms in a gas behave like a single super atom. Quantum mechanics provides essential tools for all of the sciences and for every advanced technology.

I. Comprehension check. Read the text in detail, say whether these statements

are true or false. If they are false make your own true ones.

1. The age of classical natural science differs from the contemporary one in that it tried to find the simplest answers to the no less complicated questions.

2. In 1900 Max Planck started the quantum - mechanical snowball.

3. Quantum mechanics was created on the basis of a radical renunciation of old principles.

4. Bohr’s quantum postulates led to Plank’s radiation formula.

5. Einstein created modem quantum theory.

6. The Periodic Table has no theoretical basis.

7. Quantum mechanics was created to describe an abstract atomic world. It has nothing to do with our daily lives.

III. Sum up the whole article using your notes and charts.

Unit Two FROM THE HISTORY OF PHYSICS: OUTSTANDING SCIENTISTS AND DISCOVERIES

Text 1 Ancient Physics

In ancient times, the systematic study of fundamental natural laws was not a huge concern. The concern was staying alive. Science, as it existed at that time, consisted primarily of agriculture and, eventually, engineering to improve the daily lives of the growing societies. The sailing of a ship, for example, utilizes air drag, the same principle that keeps an airplane aloft. The ancients were able to figure out how to construct and operate sailing ships without precise rules for this principle.

As the Greek civilization arose, however, there came finally enough stability

- despite the (act that there still frequent wars - for there to arise an intellectual aristocracy, an intelligentsia that was able to devote itself to the systematic study of these matters. Euclid and Pythagoras are just a couple of the names that resonate through the ages in the development of mathematics from this period.

In the physical sciences, there were also developments. Leucippus (5th century B.C.E.) refused to accept the ancient supernatural explanations of nature and proclaimed categorically that ever}' event had a natural cause. His student, Democritus, went on to continue this concept. The two of them were proponents of a concept that all matter is comprised of tiny particles which were so small that they could not be broken up. These particles were called atoms, from a Greek word for "indivisible." It would be two millennia before the atomistic views gained support and even longer before there was evidence to support the speculation.

I. Find in the text English equivalents to the following words and word combinations:

1) Фундаментальні закони природи, 2) удосконалювати щоденне життя, 3) робити розрахунки, 4) відмовитися прийняти, 5) природне «начало»,

6) прихильник концепції, 7) складатися з крихітних частинок, 8) здобути прихильність, 9) світське походження, 10) проголосити положення, 11) брак точності, 12) помилкові приклади.

П. Answer the following questions:

1. What was the purpose of the ancient science?

2. Who were the first to develop mathematics in Ancient Greece?

3. Who reached success in Ancient Greek physics?

4. Who proclaimed the concept that every event had a natural cause?

5. Who was the teacher of Democritus?

6. Who proposed that all matter is comprised of tiny particles?

7. What were the tiny particles called?

8. What did the word “atom” originate from?

9. What concepts were developed by Aristotle?

10.What is natural philosophy?

IILComprehension check. Read the text in detail, say whether these statements are true or false. If they are false make your own true ones.

1. In ancient times people showed huge concern to the systematic study of fundamental natural laws.

2. The main task of science, as it existed at that time, was to improve the daily lives of the societies.

3. The ancients were able to explain the precise rules of constructing and operating sailing ships

4. The scientists of Greek civilization were not able to devote themselves to systematic study of physical laws because of frequent wars.

5. Euclid and Pythagoras are just a couple of the names that resonate through the ages in the development of philosophy.

6. Leucippus supported ancient supernatural explanations of nature.

7. Democritus was the first who proclaimed that every event had a natural cause.

8. Euclid gave the beginning to atoms.

9. According to Democritus all matter is comprised of huge particles that can be freely broken up.

10.The atomistic views immediately gained support of the society.

IV. Summarize the text using the plan below

1. Science as it existed in ancient times.

2. Systematic studies during Greek civilization.

3. The development of atomistic views.

Text 2

The Natural Philosophy of Aristotle

While his mentor Plato (and his mentor, Socrates) were far more concerned with moral philosophy, Aristotle’s (384 - 322 B.C.E.) philosophy had more secular foundations. He promoted the concept that observation of physical phenomena could ultimately lead to the discovery of natural laws governing those phenomena, though unlike Leucippus and Democritus, Aristotle believed that these natural laws were, ultimately, divine in nature.

His was a natural philosophy, an observational science based on reason but without experimentation. He has rightly been criticized for a lack of rigour (if not outright carelessness) in his observations. For one egregious example, he states that men have more teeth than women which is certainly not true.

Still, it was a step in the right direction.

One of Aristotle's interests was the motion of objects:

• Why does a rock fall while smoke rises?

• Why does water flow downward while flames dance into the air?

• Why do the planets move across the sky?

He explained this by saying that all matter is composed of five elements: Fire, Earth, Air, Water, Aether (divine substance of the heavens).

The four elements of this world interchange and relate to each other, while Aether was an entirely different type of substance. These worldly elements each had natural realms. For example, we exist where the Earth realm (the ground beneath our feet) meets the Air realm (the air all around us and up as high as we can see).

The natural state of objects, to Aristotle, was at rest, in a location that was in balance with the elements of which they were composed. The motion of objects, therefore, was an attempt by the object to reach its natural state. A rock falls because the Earth realm is down. Water flows downward because its natural realm is beneath the Earth realm. Smoke rises because it is comprised of both Air and Fire, thus it tries to reach the high Fire realm, which is also why flames extend upward^

There was no attempt by Aristotle to mathematically describe the reality that he observed. Though he formalized Logic, he considered mathematics and the natural world to be fundamentally unrelated. Mathematics was, in his view, concerned with unchanging objects that lacked reality, while his natural philosophy focused upon changing objects with a reality of their own.

In addition to this work on the impetus, or motion, of objects, Aristotle did extensive study in other areas:

• created a classification system, dividing animals with similar characteristics into "genera."

• studied, in his work Meteorology, the nature not only of weather patterns but also geology and natural history.

• formalized the mathematical system called Logic.

• extensive philosophical work on the nature of man's relation to the divine, as well as ethical considerations.

Aristotle's work was rediscovered by scholars in the Middle Ages and he was proclaimed the greatest thinker of the ancient world. His views became the philosophical foundation of the Catholic Church (in cases where it didn't directly contradict the Bible) and in centuries to come observations that did not conform to Aristotle were denounced as heretic. It is one of the greatest ironies that such a proponent of observational science would be used to inhibit such work in the future.

I. Find in the text English equivalents to the following words and word combinations:

1) Світські засади, 2) приводити до відкриття, 3) божественний за походженням, 4) крок у правильному напрямку, 5) взаємообмінюватсь та співвідноситись один з одним, 6) атмосфера, 7) природний стан об’єкту, 8) рух об’єкту, 9) розповсюджуватись вгору, 10) безвідносні один до одного, 11) сила руху, 12) заперечувати, 13) перешкоджати, 14) прихильник.

II. Answer the following questions:

1. What kind of foundations did the Aristotle ’ s philosophy have?

2. What could lead to the discovery of natural laws according to Aristotle?

3. Why has he been criticized?

4. What was one of Aristotle ’ s interests?

5. What did he call the worldly elements?

6. What kind of connection does exist between world elements?

7. What does the motion of objects mean according to Aristotle?

8. What was Mathematics concerned with in Aristotle’s view?

9. What areas did Aristotle worked in?

10. Did Aristotle make a great contribution to the development of science?

IILComprehension check. Read the text in detail, say whether these statements are true or false. If they are false make your own true ones.

1. Aristotle was concerned with moral philosophy.

2. He promoted the concept that observation of physical phenomena couldn’t lead to the discovery of natural laws.

3. Aristotle ’ s natural philosophy has never been criticized.

4. The only Aristotle’s interest was the motion of objects.

5. All matter is composed of four elements according to Aristotle.

6. According Aristotle the motion of object was an attempt by the object to reach its natural state.

7. Aristotle made attempts to describe mathematically the reality that he observed.

8. Mathematics as well as natural philosophy were focused upon changing objects with a reality of their own.

9. The name of Aristotle is connected with the Meteorology, Logics and some other sciences.

10. Aristotle is the great thinker of ancient world.

Text3 Archimedes of Syracuse

Archimedes (287 - 212 B.C.E.) is best known for the classic story of how he discovered the principles of density and buoyancy while taking a bath, immediately causing him to run through the streets of Syracuse naked screaming "Eureka!" (which roughly translates to "I have found it!"). In addition, he is known for many other significant feats:

• outlined the mathematical principles of the lever, one of the oldest machines

• created elaborate pulley systems, reputedly having been able to move a full- size ship by pulling on a single rope

• defined the concept of the center of gravity

• created the field of statics, using Greek geometry to find equilibrium states for objects that would be taxing for modem physicists

• reputed to have built many inventions, including a "water screw" for irrigation and war machines that helped Syracuse against Rome in the First Punic War. He is

attributed by some with inventing the odometer during this time, though that has not been proven.

Perhaps Archimedes’ greatest achievement, however, was to reconcile Aristotle's great error of separating mathematics and nature. As the first mathematical physicist, he showed that detailed mathematics could be applied with creativity and imagination for both theoretical and practical results.

I. Find in the text English equivalents to the following words and word combinations:

2) Принцип щільності та здатності триматися на поверхні,

2) спричиняти, 3) визначний вияв, 3) закон ричага, 4) виштовхуючи система, 5) цент тяжіння, 6) стан рівноваги, 7) водяний гвинт, 8) лічильник пройденого шляху, 9) примиритися, 10) творчість та уява.

П, Answer the following questions:

1. What is the classical story about the discovery of principle of density and buoyancy?

2. What fields did Archimede work in?

3. What was his discovery in geometry?

4. What did he discover in the branch of Physics?

5. Which of Archimede’s discoveries helped Syracuse against Rome in the First Punic War?

6. What contribution did Archimede make in Mechanics?

7. Who was the first mathematical physicist?

8. In what way could the detailed mathematics be applied for both theoretical and practical results?

IILSummarize the text. Tell about the Archimede’s contribution to the development of science.

Text 4

Early history of electricity

History shows us that at least 2,500 years ago the Greeks were already familiar with the strange force (as it seemed to them) which is known today as electricity. Generally speaking, three phenomena made up all of man's knowledge of electrical effects. The first phenomenon was the familiar lightning flash - a dangerous power which could both kill people and bum or destroy their houses. The second manifestation of electricity was more or less familiar to people: a strange yellow stone which looked like glass was sometimes found in the earth. On being rubbed, that strange yellow stone - amber - obtained the ability of attracting light objects of a small size. The third phenomenon was connected with the so-called electric fish which possessed the property of giving more or less strong electric shocks which could be obtained by a person coming into contact with it.

Nobody knew that the above phenomena were due to electricity. People could neither understand their observations nor find any practical applications for them. All of man's knowledge in the field of electricity has been obtained during the last 370 years. It took a long time before scientists learned how to make use of electricity. Most of the electrically operated devices, such as the electric lamp, the refrigerator, the tram, the lift, the radio are less than one hundred years old. In spite of their having been employed for such a short period of time, they play a most important part in man's everyday life all over the world.

Famous names are connected with the scientific research on electricity, its history. As early as about 600 В. C. the Greek philosopher Phales discovered that when amber was rubbed, it attracted and held minute light objects. However, he could not know that amber was charged with electricity owing to the process of rubbing. Then Gilbert, the English physicist, began the first systematic scientific research on electrical phenomena. He discovered that various substances possessed the property similar to that of amber: they generated electricity when they were rubbed. He gave the name "electricity" to the phenomenon he was studying. He got this word from the Greek "electrum" meaning amber).

Many learned men of Europe began to use the new word «electricity») in their conversation as they were engaged in research of their own. Scientists of Russia, France and Italy made their contribution as well as the Englishmen and the Germans.

I. Find in the text English equivalents to the following words and word combinations:

Відомий феномен, утворювати (складати), спалах блискавки, прояв електрики, натирати, затверділий янтар, володіти властивістю, завдяки чомусь, практичне застосування, отримувати знання, мати заряд, не зважаючи на..., електроприлад, притягувати і утримувати, започаткувати дослідження.

II. Answer the questions given below:

1. What were the three phenomenon familiar to Greeks 2500 years ago?

2. Did they know that these phenomenon were due to electricity?

3. Did this phenomenon find any practical application in Greek civilization?

4. When was the first knowledge in the field of electricity obtained?

5. How old are the electrically operated devices?

6. Who was the first to observe rubbed amber attracting light objects?

7. Who began the first systematic research on electrical phenomena?

8. What properties of substances were discovered by Gilbert?

9. Why was the strange phenomena called “electricity”?

10.Who participated in studying the electricity phenomenon?

incomprehension check. Read the text in detail, say whether these statements are true or false. If they are false make your own true ones.

1. 2500 years ago the Greeks were not aware of what now is called electricity.

2. The three phenomenon that attracted Greeks’ attention were a lightning flash, a strange yellow stone, an electric fish.

3. People found various practical applications to the strange phenomenon.

4. Man's knowledge in the field of electricity has been obtained during the

last 3 hundred years.

5. Phales discovered that when amber was rubbed, it attracted but could not held light objects.

6. Substances possessed the property similar to that of rubber.

7. Word “electricity” originates from Latin “electrum”.

8. Nobody in Europe was engaged in researching electricity.

IV. Summarize the text.

Text 5

Date: 2015-02-16; view: 951