HOMEWORK
(to be done in writing)
1. Translate into Russian.
1. The magnetic field controls the movement of the particles making them travel along a single track.
2. We know gravity to act on every particle of a body so that its weight is actually distributed throughout the body.
3. It is possible, however, for the two electrons to occupy the same region if they are an antiparallel pair.
4. Light striking one side of the photocathode causes photoelectron to be ejected from the otherside into the vacuum.
5. Judging by this trend we can expect the laser to play an important role in the communication systems ofthe future.
6. In solids molecules have fixed lattice sites but their thermal motion causes them to vibrate around these equilibrium positions.
7. For such forces to be effective, matter must be compressed until it approaches the density of matter within an atomic nucleus.
8. It is also possible for the annihilation of an electron-positron pair to give rise to hadron.
2. Translate into English. Use the Complex Object and the for + Infinitive phrase.
1. Мы знаем, что они использовали новый источник информации.
2. Я полагаю, что они проведут всесторонний анализ этого процесса.
3. Для того чтобы это произошло, температура должна быть достаточно высокой.
4. Мы заставили его решить это уравнение.
UNIT SEVENTEEN
GRAMMAR: THE INFINITIVE
• Translate the following sentences into Russian. Pay special attention to the construction the Complex Subject with the Infinitive. Follow the model.
Model: A yawning ozone hole is reported to have been identified over the Antarctic.
Сообщают, что нал Антарктикой обнаружена зияющая озонная дыра.
1. Atmospheric pollution is known to have been a pressing problem for each industrialized country.
2. Harmful effects of pollution seem to have been in the news for a long time.
3. They are expected to be in the news for a long time to come.
4. Articles on smoke and offensive gases released by local factories are said to appear daily.
5. One more type of pollution proves to have appeared recently.
6. Ozone holes are assumed to be threatening the globe as a whole.
• Agree with the speaker's idea. Use the Complex Subject with the Infinitive. Follow the model.
Model: It is known that the ozone layer acts as a filter. Yes, the ozone layer is known to act this way.
1. It is supposed that the ozone layer is the thinnest over the Antarctic.
2. It is assumed that the size of the hole is increasing.
3. It is believed that the cause ofthe ozone hole is harmful chemicals.
4. It is expected that the ozone layer thinning will cause an increase of harmful radiations.
5. It issuggested that harmful ultraviolet radiations maybe very dangerous.
WORD AND PHRASE STUDY
• Pay attention to the prefixes. Guess the meaning of the following words:
trans- = across — transmit, transform, transduce, translate, transfer, transplant
mis- = wrong —misunderstand, miscalculate, mislead, mispronounce, misbehave, misinform
со- = together with — cooperate, coordinate, coincidence, coaxial, coworker
semi- = half — semiconductor, semicircle, semisphere, semifinal, semiofficial
READING (17A)
• Read the passage below and classify the symmetries described in it.
SYMMETRIES
Symmetries and apparent symmetries in the laws of nature have played a part in the construction of physical theories since the time of Galileo and Newton. The most familiar symmetries are spatial or geometric ones. In a snowflake, for example, the presence of a symmetrical pattern can be detected at a glance. The symmetry can be defined as an invariance in the pattern that is observed when some transformation is applied to it. In the case ofthe snowflake the transformation is a rotation by 60 degrees, or one-sixth of a circle. If the initial position is noted and the snowflake is then turned by 60 degrees (or by any integer multiple of 60 degrees), no change will be perceived. The snowflake is invariant with respect to 60-degree rotations. According to the same principle a square is invariant with respect to 90-degrce rotations and a circle is said to have continuous symmetry because rotation by any angle leaves it unchanged.
Although the concept of symmetry had its origin in geometry, it is general enough to embrace invariance with respect to transformations ofother kinds. An example of a nongeometric symmetry is the charge symmetry of electromagnetism. Suppose a number of electrically charged particles have been set out in some definite configuration and all the forces acting between pairs of particles have been measured. If the polarity ofall the charges is then reversed, the forces remain unchanged.
Another symmetry ofthe nongeometric kind concerns isotopic spin, a property of protons and ofthe many related particles called hadrons, which are the only particles responsive to the strong force. The basis of the symmetry lies in the observation that the proton and the neutron are remarkably similar particles. They differ in mass by only about a tenth of a per cent, and except for their electric charge they arc identical in all other properties. It therefore seems that all protons and neutrons could be interchanged and the strong interactions would hardly be altered. If the electromagnetic forces (which depend on electric charge) could somehow be turned off, the isotopic-spin symmetry would be exact; in reality it is only approximate.
Although the proton and the neutron seem to be distinct particles and it is hard to imagine a state of matter intermediate between them, it turns out that symmetry with respect to isotopic spin is a continuous symmetry, like the symmetry of a sphere rather than like that of a snowflake.
All the symmetries wc discussed so far can be characterized as global symmetries; in this context the word global means "happening everywhere at once". In the description of isotopic-spin symmetry this constraint was made explicit: the internal rotation that transforms protons into neutrons and neutrons into protons is to be carried out everywhere in the universe at the same time. In addition to global symmetries, which arc almost always present in a physical theory, it is possible to have a "local" symmetry, in which the convention can be decided independently at every point in space and every moment in time. Although "local" may suggest something of more modest scope than a global symmetry, in fact the requirement of local symmetry places a far more stringent constraint on the construction of a theory. A global symmetry states that some law of physics remains invariant when the same transformation is applied everywhere at once. For a local symmetry to be observed the law of physics must retain its validity even when a different transformation takes place at each point in space and time.
• Re-read the passage and find English equivalents for the following Russian terms.
симметрия — явная/пространственная/(не)геометрическая/в мировом масштабе/локальная/нспрерывная/сп ии-изотопная/зарядная
• Look through the passage and find English equivalents for the following Russian phrases.
с первого взгляда; удивительно схожие частицы; вряд ли бы изменились; по-видимому, разные частицы; повсюду; одновременно; можно принять условие; намного более сильное ограничение; сохранить свое значение
• Answer the following questions.
1. What is symmetry?
2. Why is the concept of symmetry important?
3. What symmetries are there in the world?
4. What arc the most familiar of them and why?
5. What symmetries are called local/global?
6. What examples of gcometrie/nongeometric symmetries could you give?
CLASSWORK
READING (17B)
• Read the article by Graham P. Collins from May 2001 and make an appropriate comment on the discovery made. What does the author mean by the title? What dog and what trick docs he mean?
NEW TRICK FROM OLD DOG
A Magnesium Compound Is a Startling Superconductor by Graham P. Collins
You can buy magnesium boride ready-made from chemical suppliers as a black powder. The compound has been known since 1950s and has typically been used as a reagent in chemical reactions. But until this year (2001) no one knew that at 39 degrees above absolute zero it conducts electric current perfectly — it is a superconductor. Although its superconducting temperature is far below that ofthe copper oxide high-temperature superconductors, the compound has set off a flurry of excited activity among researchers. Magnesium boride overturned theorists' expectations and promises technological applications.
Jun Akimitsu of Tokyo University anounced the surprising discovery at a conference in Japan on January 10, after he and his workers stumbled on magnesium boride's properties while trying to make more complicated materials involving magnesium and boron.
Word ofthe discovery spread around the world by e-mail and in three weeks the first research papers by othergroups were posted on the Internet.
In early March, a special session on magnesium boride was hastily put together in Seattle at the American Physical Society's largest annual conference: from 8 p.m. until long after midnight, nearly 80 researchers presented ultrabrief summaries on their results.
Until January, standard wisdom ruled out the possibility of a conventional Superconductor operating above about 30 kelvins. Conventional superconductors are understood by the so-called BCS theory, formulated in 1957. The magnesium boride result seemed to imply that either a new superconducting mechanism had been discovered or that the BCS theory needed to be revised.
Almost all the experimental evidence so far supports the idea that magnesium boride is a standard BCS superconductor, unlike the copper oxides. For example, when researchers use the isotope boron 10 in place of boron 11, the material critical temperature rises slightly, as expected, because the lighter isotope alters vibrations ofthe material's lattice of atoms, a key component of BCS theory. How, then, has the magic 30 kelvins been exceeded?
Perhaps, those predictions were premature. Magnesium boride has a combination of low-mass atoms and favourable electron states, that was overlooked as a possibility.
Physicists are trying to push the BCS' limit even further to produce higher critical temperatures by doping the material with carefully selected impurities. Groups have added aluminium or carbon (neighbours of boron in the periodic table), but these both decrease the critical temperature. Calcium is expected to work better, but no one has succeeded in producing calcium-doped magnesium boride.
Even undoped, magnesium boride has several attractive features for applications. First, the higher operating temperature would allow cooling ofthe superconductor by refrigeration instead of by expensive liquid helium, as is needed for the most widely used superconductors.
The high-temperature copper oxide superconductors beat magnesium boride hands-down on that count but they have proved difficult to manufacture into convenient wires. Also, the supcrcurrent does not flow well across the boundaries of microscopic grains in copper oxides.
Magnesium boride, in contrast, has already been fashioned into wires using simple techniques, and the supercurrent flows effortlessly between grains. One drawback, however, is that magnesium boride loses its superconductivity in relatively weak magnetic fields, fields that are inescapable in applications. But with the progress seen already in a scant few months, researchers are confident they can overcome such problems.
HOMEWORK
(to be done in writing)
1. Translate into Russian. Pay special attention to the word one in different meanings.
1. We could offer you a number of challenging problems, but this one seems to be the most attractive.
2. One should find a simple and elegant solution ofthe problem.
3. No one seems to have dealt with this problem yet.
4. One should mention the problem under investigation in our lab.
5. No one seems to have formulated this problem in precise terms.
6. This is one ofthe most confusing and puzzling problems we have ever dealt with.
7. This problem seemstobc much more complicated than all the previous ones.
8. No one has yet presented it in all its complexity.
2. Translate into English.
Зеркальная (mirror/reflection) симметрия является первым случаем геометрического понятия симметрии, относящейся к таким операциям, как отражение или вращение. Симметрия является той идеей, посредством которой человек на протяжении веков пытался понять и создать порядок, красоту и совершенство (perfection). Первые (early) ученые считали окружность на плоскости и сферу в пространстве наиболее совершенными геометрическими фигурами.
Что можно назвать математической философией левого и правого? Сточки зрения научного мышления, между левым и правым не существует полярной противоположности. Пространство изучается геометрией. Но пространство также служит средой всех физических явлений. Структура физического мира проявляется (reveal) во всеобщих законах природы. Во всей физике нет ничего, что указывало бы на внутреннее различие между левым и правым. Левое и правое эквивалентны так же, как все точки и все направления в пространстве.
UNIT EIGHTEEN
GRAMMAR: ГЛАГОЛ WOULD
Would Глагол обозначает волеизъявление, желание, склонность к выполнению действия. Чаще употребляется в отрицательной форме, означая упорное нежелание совершить действие. Относительно неодушевленных предметов или явлений означает неспособность предмета выполнитьдействие,для которого он предназначен, или недостаточность условий для реализации явления.
Would not We did everything to persuade him but he would not change (Никак) не the procedure of his experiment.
Мыделали все, чтобы убедить его, ноон(никак) не хотел изменить процедуру эксперимента.
Would
1) a) Future in the Past
He wrote he would return in a week. Он писал, что вернется через неделю.
b) The Subjunctive Mood
It would be extremely interesting to attend this conference. Было бы очень интересно присутствовать на этой конференция.
2) a) We tried to open the door but it wouldn't.
Мы пытались открыть дверь, но она никак не открывалась.
Ь) вежливая просьба
Would you give me your English textbook?
He дадите ли мне ваш учебник по английскому языку?
3) would = used to — бывало, обычно, имел обыкновение
Не would work (used to work) in his lab for ten hours.
Он имел обыкновение работать всвоей лаборатории по 10 часов.
Note: В научно-технической литературе would в этом значении на русский язык не переводится.
Sometimes the device would fail. Иногда прибор ломался.
• Sentences to be translated.
1. We asked them whether they would change the conditions of the experiment.
2. They tried to raise the temperature but it wouldn't.
3. The device was tested several times and it would always prove correct.
4. Were the surface of the material highly polished, the friction would be less.
5. There would be no progress in science without observations.
6. The density of the medium would change with temperature no matter what measures they took.
7. There were electron tube devices in our laboratories but now they are replaced by semiconductor ones.
8. It would be desirable that all necessary calculations be made before the experiment starts.
WORD AND PHRASE STUDY
anypron. — любой, всякий (утверд. предложение)
any kind — всякого рода
in any case (event) - в любом случае
any longer - больше не (syn. any more, no longer, no more)
hardly any — почти ничего
if any - если вообще (таковые имеются), если только
• Sentences to be translated.
1. If this is the case, it is difficult to measure any internal properties of the plasma by any ofthe conventional methods.
2. One can obtain very poor, if any, data on this event.
3. Any of these approaches will hold.
4. Гп any event one should bear in mind that the information obtained may be misleading as to the course ofthe reaction.
READING (18A)
• Read the passage below and find the answer for the following question:
Which symmetries, global or local, hold the greatest interest for physicists today and why?
GAUGE THEORIES1
An understanding of how the world is put together requires a theory of how the elementary particles of matter interact with one another. Equrvalently. it requires a theory of the basic forces-of nature. Four such forces have been identified, and until recently a different kind of theory was needed for each of them. Two ofthe forces, gravitation and elcctromagnetism, have an unlimited range; largely for this reason they arc familiar to everyone. They can be felt directly as agencies that push or pull. The remaining forces, which are called simply the weak force and the strongforce, cannot be perceived directly because their influence extends only over a short range, no larger than the radius of an atomic nucleus. The strong force binds together the protons and the neutrons in the nucleus, and in another context it binds together the particles called quarks that are thought to be the constituents of protons and neutrons. The weak force is mainly res ponsible forthe decay of certain particles.
A long-standing ambition of physicists has been to construct a single master theory that would incorporate all the known forces. One imagines that such a theory would reveal some deep connection between the various forces while accounting for their apparent diversity. Such a unification has not yet been attained, but in recent years some progress may have been made. The weak force and elcctromagnetism can now be understood in the context of a single theory. Although the two forces remain distinct, in the theory they become mathematically intertwined. What may ultimately prove more important, all four forces are now described by means of theories that have the same general form. Thus if physicists have yet to find a single key that fits all the known locks, at least all the needed keys can be cut from the same blank. The theories in this single favored class are formally designated non-Abelian gauge theories with local symmetry. What is meant by this forbidding label is the main topic of this article. For now, it will suffice to note that the theories relate the properties ofthe forces to symmetries of nature.
Gauge theories — градиентные полевые теории, или калибровочные теории поля
• Look through the passage and And English equivalents for the following Russian terms and phrases:
как построен мир; до недавнего времени; не больше чем; в основном, отвечая зд...; единым ключ, который подходит ко всем замкам; достаточно заметить; согласно тому же принципу; основные силы природы; слабые/сильные взаимодействия
• Answer some more questions about the passage.
1. What is a long-standing ambition of physicists?
2. What do scientists mean by a single master theory and why is it needed?
3. How many and what basic forces of nature have been identified until recently?
4. Which of these forces have a limited/an unlimited range?
5. Which of the basic forces are familiar/unfamiliar to everyone and why is it so?
6. What are the strong/weak forces responsible for?
7. What progress has been made recently in developing a theory of the basic forces of nature?
8. By means of what theories are the basic forces of nature described now?
• Study the block-scheme below and try to discuss or summarize the problem as a whole.
Forces
 |
weak
strong
intertwined
radioactive beta decay
pull/push
proton/neutron binding
CLASS WORK
READING (18B)
• Study the table given below. Read the passage and be prepared to discuss the problem using this table.
THE FORCES IN NATURE | |||
TYPE | INTENSITY OF FORCES (Decreasing order) | BINDING PARTICLE (Field quantum) | OCCURS IN |
STRONG NUCLEAR FORCE | ~ 1 | GLUONS (no mass) | ATOMIC NUCLEUS |
ELECTROMAGNETIC FORCE | - io-3 | PHOTON (no mass) | ATOMIC SHELL APPL1C. OF ELECTRICITY |
WEAK NUCLEAR FORCE | ~io-5 | BOSONS Z°, W\ W(hcavy) | RADIOACTIVE BETA DECAY |
GRAVITATION | ~io-38 | GRAVITON? | H EAVEN LY BODIES |
THE EXCHANGE OF PARTICLES IS RESPONSIBLE FORTHE FORCES
THE FOUR FORCES OF NATURE
One of the major achievements of modern physics has been the development over the past 20 years or so of a new class of grand unified theories to describe the forces acting between elementary particles.
There arc four different ways in which the various particles that make up the Universe can interact with one another. Each of these is a particular variety of interaction, or to use a more old-fashioned but more common term, a force (the forces are nuclear, electromagnetic, weak, gravitational). Of the four forces, two — the nuclear force and the weak force — make themselves felt only at incredibly tiny distances of 1013 centimeters or less. This is just about the width of the tiny nucleus that exists at the very center of the atom. It is only within the nucleus, in the immediate neighbourhood of isolated particles, that these forces exist. For this reason the term nuclear force is sometimes given to both, and they are differentiated by their relative strength into the strong nuclear force and the weak nuclear force. The weak force is responsible for such processes as the beta decay of a radioactive atomic nucleus; the strong nuclear force holds the nucleus together. The electromagnetic force governs the interaction of electrically charged particles; and gravity holds the Universe together.
Until the theories were introduced the four observable forces of nature seemed to be independent of one another. Two of these forces, the electromagnetic force and the weak nuclear force, arc already linked by the highly successful electrowcak theory, which treats them as different manifestations of a single underlying force. According to the prevailing view ofthe interactions of elementary particles, the force is transmitted between two particles by the exchange of a third, intermediary particle.
Such a description is the essence of a quantum field theory. In electromagnetic and weak interactions the exchanged particle is a member ofthe family called the vector bosons, named after the Indian physicist S.N. Bose. This term refers to a classification of particles according to one of their most basic properties: spin angular momentum. A boson is a particle whose spin, when measured in fundamental units, is an integer such asO, 1 or 2. "Vector" designates a boson whose spin value is equal to 1.
In the case ofelectromagnetism the exchanged vector boson is the photon, the massless and chargeless "wave packet" of electromagnetic energy that functions as the quantum ofthe electromagnetic field. The other two forces — gravity and st rong nuclear force — are thought to be transmitted by intermediary particles, namely the graviton and the eight particles called gluons.
The unified eleotroweak theory is the theory that predicts the existence of the three massive particles called intermediate vector bosons (also known as weakens; "intermediate" simply because of their mediating role between particles). The electroweak theory, which can now be considered the "standard" account of electromagnetic and weak interactions, for the first time made specific and testable predictions about the properties of intermediate vector bosons, including their mass. The goal of attempts to create a grand unified theory is to arrive at a more comprehensive mathematical structure that would incorporate both the electroweak force and the strong nuclear force (omitting only gravity, the fourth known force).
Scientific American, August, 1982
• Find equivalents for the following phrases.
лают о себе знать; различные проявления одной, лежащей в их основе силы; в соответствии с общепринятым мнением; целое число; обычное объяснение электромагнитных...; слабое взаимодействие; сильное взаимодействие; теория великого объединения;...в непосредственной бл изости...
• Re-read the passage and answer the questions.
1. What is one of the major achievements of modern physics over the past 20 years?
2. Where do the nuclear force and the weak force make themselves felt?
3. What does the term "nuclear force" imply?
4. What is the weak force responsible for?
5. What is the strong force responsible for?
6. What forces are linked by means of the electroweak theory?
7. What is the exchange particle in the electroweak force?
8. How many bosons does the unified electroweak theory predict?
9. What is the goal of creating a grand unified theory?
• Match each word in column I with its synonym in column II.
I
apparent, to attain, to come about, to designate, familiar, decay, with respect to, ultimately, explicit, to reveal
• Choose the proper word.
II
definite, to name, to show, as regards, finally, evident, to achieve, to happen, disintegration, well-known
1. The strong force (separates/binds together/breaks) the protons and the neutrons in the nucleus.
2. The gauge theory will (designate/reveal/relate) some deep connection between the various forces.
3. In the theory the two forces become mathematically (unified/defined/ intertwined).
4. The theories in this single favored class are formally (designed/ designated/defined) non-Abelian gauge theories with local symmetry.
5. For a local symmetry to be observed this law of physics must retain its (value/valence/validity).
6. It is hard to imagine a state of matter (immediate/intermediate/internal) between the proton and the neutron.
HOMEWORK
(to be done in writing)
1. Translate into Russian.
Pull of Gravity Reveals Unseen Galaxy Cluster
Now astronomers are taking long strides into the realm (область) of dark matter. The scientists of Bell Labs in Murray Hill, New Jersey have discovered a whole new cluster of galaxies and calculated its distance without relying on
its emitted light. Instead they inferred the unseen cluster's existence from the way its gravity rerouted light from more distant galaxies beyond. The research team is one ofscveral to show that the technique, known as gravitational lensing, can be used to map matter in deep space.
Astronomers believe that about 90% of mass in the universe is dark. Telescopes can't see it, but its gravitational pull blows its cover. "Gravity doesn't care whether matter is dark or luminous," scientists say. All you need are background sources of light, which arc all over the sky, and, in principle, you can find all the matter between us and the background sources.
Science (17 August 2001)
2. Translate into English.
1. Желательно, чтобы прибор проверили до эксперимента.
2. Если бы ты присутствовал на лекции вчера, ты бы понял новый матсри&т лучше.
3. Мне бы хотелось, чтобы ты информировал нас о работе каждую неделю.
4. Без атмосферы не было бы жизни.
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