HOMEWORK
(to be done in writing)
1. Translate some sentences paying attention to following and followed.
1. The calculations following the experiment gave accurate results.
2. The lecture followed by the demonstration of experiments was a success.
3. The practical studies following the theoretical ones were of great use.
4. Following this new method they achieved good results.
5. 108 is a number expressed by one followed by eight zeroes.
6. Experiments of many other scientists following Rutherford's research proved his predictions.
2. Translate the following sentences into English using the Participle.
1. Двигаясь (при движении) по кругу с одинаковой скоростью, тело непрерывно изменяет свое направление.
2. После того как прибор прошел тщательное испытание, его ввели в эксплуатацию.
3. Луч лазера имеет почти неограниченные возможности применения в промышленности.
4. Нейтрон — частица, имеющая одинаковую массу с протоном, но не несущая электрического заряда.
5. Так как измерения проводились неточными приборами, данные были ненадежными.
6. Испытываемое оборудование требует дальнейшего усовершенствования.
UNIT SIX
GRAMMAR: THE ABSOLUTE PARTICIPIAL CONSTRUCTION
1. S + Participle; S + Predicate
так как, когда, если, послетого как...
All preparations having been made, Когда все приготовления были
they started the experiment. сделаны, они начали экспери-
мент.
2. S + Predicate; S + Participle
... причем, а, и
Hydrogen is the simplest substance, Водород является простейшим
atoms of all other elements having веществом, а атомы других
a more complex structure. веществ имеют более сложную
структуру.
Примечание: Иногда незанисимый причастный оборот вводится предлогом
with. Обороты такого типа в начале предложения переводятся придаточным
предложением с союзами: теперь, когда; при условии, когда; так как; а в конце
предложения — самостоятельным предложением с союзами а, и, при этом.
With the experimentsltearrietf out, Когда опыты были завершены, они
they started new investigations. начали новые исследования.
• Sentences to be translated.
1. An electron leaving the surface, the metal becomes positively charged.
2. A magnet is broken into two parts, each piece becoming a magnet with its own pair of poles.
3. All the liberated electrons having reached the anode, saturation occurs.
4. The temperature ofthe conductor being raised, the motion of electrons also increases.
5. The nucleus of an ordinary hydrogen atom consists of one proton, with one electron moving around it.
WORD AND PHRASE STUDY
whether conj. — ли (относится к последующему глаголу) whether... or (not) — независимо от того + ли (относится к глаголу) as to whether — относительно того + л и (относится к глаголу)
Translate the sentences into Russian. Pay attention to the conjunction whether which corresponds to the Russian ли. Begin translation with the predicate.
Model: We are not sure whether this hypothesis is true. Мы не уверены, верна ли эта гипотеза.
1. Questions arise as to whether our usual belief about our Universe is strictly correct.
2. For example, one might ask whether the dimensionality of space and time can undergo evolution.
3. Whether our Universe is finite or infinite is still not clear.
4. Until now scientists have no evidence whether there exists any invisible matter in the Universe.
5. There is practically no evidence as to whether protons are stable or can decay.
6. Many scientists doubt whether the honeycomb hypothesis ofthe Universe structure is valid.
READING (6A)
|
There are a few hypotheses concerning the structure and origin of the Universe. One of them will be presented in the passage below. Before reading the passage look at the block-scheme where some of the problems in studying the Universe are presented. Think what you know about each ofthe problems. Then read the passage. Find the ideas that were not known to you before reading.
Origin —> time/composition/evolution
The Universe <^--------- > Structure —> matter distribution
Matter —> principal constituents
THE UNIVERSE IS A HONEYCOMB
What docs our Universe look like? Docs it conform to the popularly held concept of a black abyss with islands of galaxies dispersed through it with no boundaries or shape? Apparently, it does not. "The Universe has a clear-cut •a met lire," says astronomer D.Sc. Jaan Einasto, who heads the sector of the physics ofgalaxicsat the Institute of Astrophysics and Atmospheric Physics ol'ihe Estonian Academy of Sciences. Imagine a honeycomb! This is not a hypothesis! Einasto says he has the evidence to prove it. What do wc know about the Universe? First, it came into being as a result of the " Big Bang" some 20 billion years ago. This creation was a fantastically quick, but precisely accurate process. In moments, the composition of all matter was formed: electrons, neutrons, protons, barions and other particles. Through subsequent expansion, this matter, which originally was in a state of Miperdcnsc and superhot plasma, cooled and condensed into the galaxies, •aars and planets.... Second, the "Big Bang" process continues. We arc still living in an expanding Universe. This is proved by the galaxies "running" away in different directions.
What was there before the bang, before this "beginning of all beginnings"? Science still has no answer, because all the known laws of physics only became meaningful instants after the bang.
What is in store? Shall wc continue to infinitely expand, or will the Universe, ■ ii some point, begin to contract again? The answer lies hidden in the matter contained in the Universe.
What does the "honeycomb" have to do with the Universe? — The structure of the Universe discovered explains a great deal. At the beginning and in the first stage of expansion, matter was distributed uniformly. Scientists came to understand this in the 60s, when the relic electromagnetic radiation which lemaincd since the blast was discovered. This radiation originally had the same temperature as matter and, therefore, expanded along with it. But now it has cooled off, just as matter itself, and the temperature of this radiation (weak ladiowaves) that pierces space is the same everywhere — something about 3° Kelvin (approximately —270°C). In other words uniformity is a major property ol'thc Universe.
And yet, at the very beginning, there were some processes which led to the formation of stars, galaxies, accumulations, i.e. to the condensation of matter. I hese non-uniformities show that a pattern something like a gigantic honeycomb with a diameter of 100-200 megaparsec (a megaparscc is 30 million light years) has been created. The "walls" of the cells are made of accumulations of galaxies, and where they meet, the accumulations are more numerous and the radiation in the X-range is more intensive. In other words, the comb is a real structure.
How is it that the freely moving galaxies evolved into this particular lormation? Is this chance occurrence? —The "rigidity" of the structure indicates that the "combs" themselves appeared initially and then galaxies. How can this paradox be explained? — Most likely the "combs" came into being when the galaxies were still in theirgascous state. To use an analogy, imagine two gas bubbles expanding towards each other. The more they expand, the greater the compression between them. At a certain moment they collide. This is when a certain flat formation originates between them, which Academician Yakov Zel'dovich called a "pancake" in his hypothesis which led to the idea of the cellular structure ofthe Universe. The joining of a multitude of these "pancakes" represents the walls of the gigantic "combs" in which the galaxies have accumulated.
Ifthere are "combs", one would assume there should be "honey"? Could it be that all the matter of the Universe went into the "walls" and the cells themselves arc empty? — There is no visible matter there. But it is very difficult to conceive of a physical process which would absolutely cleanse these tremendous cavities of everything. So, perhaps, we just don't sec this substance. We have to assume the existence of some invisible mass whose attraction influences the movement of galaxies, thus maintaining the structure ofthe "combs". This mass should be many times greater than the visible matter in the areas of accumulation, i.e. in the "walls". The density of the "invisible" substance should also be far higher.
Do scientists mean the neutrinos? — Yes, they do. Until recently it has been believed that the neutrino has no rest mass and moves with the speed of light, without interacting with anything in its path. But the sensational findings of a group of investigators led by V. Lyubimov (the Institute of Experimental and Theoretical Physics) show that the rest mass ofthe neutrino is larger than zero. This means that the neutrino, which literally floods the Universe is, regardless of its negligible mass, the principal matter of the Universe and hence the principal part of its entire mass. The conventional matter in the Universe comprises but only three percent. It is most likely that the "combs" themselves and the entire cellular structure ofthe Universe is the result of their force of gravity.
The future ofthe Universe is in its structure. We have to know whether it is finite. Within a "finite" Universe, the galaxies, after thousands of millions of years have passed, will inevitably begin a reverse process, and expansion will give way to contraction. Our Universe will again become a "dot" and everything will be repeated. And so on for ever and ever...
• Find English equivalents for the following Russian phrases.
общепринятое представление; масса покоя; буквально наводняет; сверхплотная плазма; распределялась однородно; гигантские соты; основное свойство; со времени взрыва; в мгновение ока; первая стадия расширения; на смену расширению придстежатие; навсегда; во много раз больше; появилась первоначально; невзирая на пренебрежимо малую массу; неизбежно начнет обратный процесс; всего ли:.л> 3%; общепринятая концепция; черпая бездна
• Mutch each word in Л with its synonym in B.
Л. relic, evidence, moment, to reverse, to conform, multitude, to occur, to come into being
H. instant, to correspond, something surviving from the past, a great
number, to turn in an opposite direction, to originate, proof, to happen
• Match each word in Л with its antonym in B.
Л. expansion, meaningful, conventional, relic, rigidity, to contract, to disagree
B. to expand, uncommon, modern, flexibility, meaningless, contraction, to conform
• Complete the sentences with information from the text or any other sources.
I. The passage deals with....
2. According to Jaan Einasto's hypothesis the Universe has a...structure.
3. The Universe came into being... ago as a result of....
4. The matter ofthe early Universe was in a state of....
5. Scientists speak about the composition of matter in terms of....
6. Some scientists assume that at the moment of the blast matter was distributed....
7. They find support to this idea in the discovery of....
8. Our Universe continues to... and the galaxies....
9. The visible matter of the Universe accounts only for....
10. Scientists assume... to account for the rest ofthe mass.
• Think and find arguments lo prove that:
a) one of the major properties of the Universe is its uniformity on a large scale;
b) despite their negligible size, neutrinos can account for the most of the Universe mass;
c) surveys show that the Universe has a clear-cut structure.
• What would you say of our current knowledge of
1. the structure of the Universe?
2. the distribution of matter?
3. the history of the Universe evolution?
CLASSWORK
RF.ADING (6B)
• Read the passage (4 min.) and answer the questions.
1. What scientific discoveries are needed to say that the Universe will be developing according to Scenario 1?
2. What scientific discoveries should the intelligent beings make to avoid the fate of our Universe according to this scenario?
SCENARIO 1. A FINITE SMALL UNIVERSE
The universe can only be finite if there is enough matter inside it to curve space-time so that it closes on itself. We do not know whether there is enough matter to do this. *We do know that the amount of visible matter is at least one-tenth as much as we calculate is necessary for this to happen — and that there may be enough matter that is presently invisible to make up the difference.
Some of this invisible matter may exist in the form of neutrinos, neutral particles that interact only very weakly. Neutrinos exist in the universe in large enough numbers so that if they have a small mass they could provide enough energy density to close the Universe. *The same may be true about other, presently unknown, subatomic particles.
If there is enough matter present to make the universe finite then there is also enough to cause the expansion to eventually stop and be replaced by a contraction. If this is the actual condition in our universe then we would like to know when this changeoverWxW occur. We cannot say this precisely, because of lack of information about the actual amount of matter in the universe, but we can say that it will not happen for a longtime, probably at least as long as the time since the Big Bang — 10 to 15 billion years.
*It is usually assumed that the size of a finite universe would only be a few times larger than the size of that part we are presently aware of, about lO" kilometers in radius. Yet there is no good reason for believing this cither on the basis of observation or of theoretical cosmology. If it were true, then the universe would begin contracting at a time in the future that is not much longerthan it has already lived, so that our universe could be said to be middle-aged.
In this scenario, which I call the finite small universe, the future of the universe does not depend much on the details of particle physics. We know that nothing much can happen to change the properties and distribution of the subatomic particles in the universe over the next few tens of billions of years, until the density of matter becomes very high through the prolonged contraction of space-time. For example, we know that if protons are unstable, their lifetime isat least 10-'"timcsgrcatcrthan the present age ofthe universe, sothat in the scenario under discussion, very few protons would have time to decay before
I he universe contracts back to the Big Crunch. Even the behaviour of much larger constituents of the universe, such as many stars and galaxies, would remain pretty much as they are now during the remaining expansion time for lhe universe.
The study of particle physics as it relates to the future of the finite small universe is interesting only at two points: when the expansion is reversing to a collapse, and when the collapse reaches its final stages.
Long before the collapse reaches its final stages, any of the large material structures such as stars, planets and their inhabitants that exist in the current universe will have been destroyed by the increase in temperature and density I hat will take place duringthe period of contraction. Perhaps the most significant question about any finite universe is whether there is some way that intelligent beings could avoid being caught up in the eventual Crunch. Even optimistic writers, such as the American physicist Freeman Dyson, have asserted that this is probably hopeless. Yet I think that even in this scenario, the ultimate future for intelligence may not be completely bleak (мрачный). The basis for my optimism is the notion that the space-time that we inhabit is not all there is, a view that a number of physicists have considered seriously, both for finite and infinite space-times. *For example, it is intellectually irresistible to think of a finite universe as embedded in some larger universe, with a higher number of dimensions, just as the two-dimensional, finite surface of the earth lies in ilnee-dimensional space. *Indeed, the mathematical description of a finite universe makes use of such an embedding into a five-dimensional space-time. I nis approach to the idea of extra dimensions is different from the one discussed previously, because here the extra dimensions are not tiny in extent. *Conceivably, both types of extra dimensions might exist. If there are large extra dimensions we are free to speculate that other realms lie in this larger universe, and that their evolution need not parallel that of our own.
At present, this is no more than a science-fiction plot. However, if there are more dimensions than those wc know, or four-dimensional space-times in addition to the one we inhabit, then I think it very likely that there are physical phenomena that provide connections between them. *lt seems plausible that if intelligence persists in the universe, it will, in much less time than the many billions of years before the Big Crunch, find out whether there is anything to this speculation, and if so how to take advantage of it.
• The passage could be divided into two parts. Where would you divide it? Why? What is each part about?
• Try to guess the meaning of the italicized phrases in the text.
• Translate the sentences marked with an asterisk.
• Say a few words about lack of knowledge or insufficient knowledge in the field of astrophysics. Use the following phrases to introduce your statements:
I. Until now we don't know whether....
2. We still don't know where....
3. We don't know yet how....
4. Until now we know almost nothing about....
5. We still lack precise knowledge of....
Think and say a few words about:
a) the fate of a finite small universe;
b) lack of scientific facts in favour of this scenario;
c) the fate of the intellectual beings.
HOMEWORK
(to be done in writing)
1. Translate into Russian.
1. Alongside the familiar four fields mentioned above, the unified theories include another kind of fields, so-called scalar fields which have some interesting and unusual properties.
2. All the four known forces of nature are vector fields having both magnitude and direction at every point of space.
3. A scalar field has only magnitude and we might think of a property such as temperature or density of a liquid as being represented by a scalar field associated with each point through the volume of the field.
4. A uniform homogeneous scalar field is almost unobscrvable but filling the whole universe it effects the properties of all elementary particles.
5. The idea of scalar fields is useful in constructing unified theories because it helps to determine masses of elementary particles and the way they interact with other particles.
2. Translate into English. Use the conjunction whether.
1. Я не уверен, стоитли заниматься этой проблемой.
2. Они сами не знают, будет ли она представлять интерес для промышленности.
3. Никто не знает, применима ли данная теория к решению широкого круга (range) проблем.
4. Мы не уверены, достаточно ли надежна методика этой серии экспериментов.
5. Неясно, имеет ли только что разработанный метод какие-то преимущества.
UNIT SEVEN
GRAMMAR: INVERSION
В бессоюзных условных предложениях, начинающихся с глаголов were, had, could, should, союз опускается.
Перевод таких предложений следует начинать с союзов если бы, при условии, что и т. д.
Например:
Were there any relationship between these events, we would certainly act differently.
Should they show any uncertainty, we would see it.
Примечание: Русское выражение «Если бы не...» переводится следующим образом:
If it were not for Were it not for |
Если бы не But for — для любого времени
If it had not been for Had it not been for |
для настоящего и будущего времени
But for
If it were not for Were it not for
this fact, the data obtained would be correct.
Если бы не этот факт, то полученные данные были бы точными.
• Sentences to be translated.
1. Had the collisions been considered in this case, the equation could have been obtained.
2. Were it not for the problem of radioactivity, the development of nuclear-powered aircraft would be much simpler.
3. Were the problem solved it would become possible to avoid these difficulties.
4. Could sound propagate in interplanetary space, it would cover this distance in 14 years.
5. Had you warned me beforehand, I would have been more careful.
6. But forthe several recent discoveries in optics, the instrument in question could not have been designed in its present form.
7. Were it not for the computer they might not make the necessary calculations on time.
WORD AND PHRASE STUDY
Инверсия, как правило, употребляется при эмоциональном выделении или подчеркивании членов предложения. Инверсия может иметь место в следующих случаях:
1. В предложениях, начинающихся наречиями. Например:
Here comes (вот идет) our friend. Thus began our friendship. So ended this terrible struggle.
2. Когда предложение начинается с распространенного обстоятель-
ства. Например:
То this branch of physics was added another one.
Гп front of the first screen are placed two other screens, each having a small hole in it.
В предложениях, начинающихся наречиями hardly едва, no sooner как только, never, seldom, often, not only, little и др. Например:
Never have I known such a man! Little did we think of our future then.
• Sentences to be translated.
1. Fundamental to all physical sciences are the concepts associated with the atomic theory of matter.
2. Satisfactory as the theory is, it cannot account for all the data obtained.
3. Only by means of the Space Telescope can we detect distant stellar objects.
4. No sooner did they switch on the device than it burnt out.
5. Nowhere before could we observe such a strange phenomenon.
READING (7A)
■ Read the passage carefully and find facts to prove or disprove the idea that the h-.m-uomb '-tniriip e of the Universe can be explained in terms ofthe chaotic inflation 'npothesis.
CHAOTIC INFLATION
Since 1980, cosmologists have modified considerably their theories ofthe 'licsi stages ofthe evolution of the Universe. This modification is based 111 ><>11 the so-called "inflationary" Universe scenario. The most promising version of this idea — "chaotic inflation" is described below by Andrei Lindc, ти- ofthe architects of the new model.
The essence ofthe inflationary hypothesis is that we live in a single domain hi' the Universe, a region corresponding to one crystal domain, which has
■ \pandcd so much ("inflated") that the domain walls are far beyond the range
. il our telescopes. The few monopolcs present in the original small volume of 11 к-1.'niverse that has been blown up to the scale of 10-8 cannot play a significant mil- in the evolution of our local bubble of space-time, so that the concept и-moves the monopole problem. But how and why did the Universe as we know inflate in this way?
1'he first version ofthe inflationary Universe was suggested by Allan Guth
i M IT, USA) in July 1980. His scenario was based on the idea of high-
..... pet attire phase transitions, which provided the energy fora rapid burst of
■ \pausion early in the life ofthe Universe. Like watergiving up its latent heat of fusion as it freezes, those phase transitions, Guth suggested, might give up i-iiergy, which went to make the Universe expand exponentially for a short i ime. But as Guth himself pointed out at the time, this early version of inflation predicted an extremely inhomogencous state for the Universe afterthe phase i i.uisition.
In October 1981, I put forward an improved version of the inflation idea, which, forobvious reasons, became known as the "new inflationary scenario". I his resolved some of the difficulties in Guth's original version. This new inflationary scenario caused a stir among cosmologists and physicists, and was u-гу widely discussed. New inflation resolved many ofthe large discrepancies between the predict ions of field theory and the observations ofthe real Universe, and suggested that we were on the right way towards an understanding ofthe I inverse birth. But even this variation proved impossible to reconcile completely with the most realistic theories of elementary particles developed. In I9S3, however, 1 was able to resolve most of those remaining difficulties with another variation ofthe inflationary scenario, called "chaotic inflation". 1'his abandons the idea that high-temperature phase transitions provided the push behind the inflation in the very early Universe. In my opinion this scenario i: much simpler and more natural than other versions ofthe inflationary I i ''verse.
Order out of Chaos
According to the unified theories of particle physics, the Universe is filled with many types of uniform, homogeneous scalar fields. The nature of each field is determined by the position of a minimum in its potential energy function, the field rolling down to its minimum as the Universe cooled. But at the very early stages of the Universe evolution, when none of the fields had yet had time to roll down into its minimum state, each field could be homogeneous and have a different value in different parts of the Universe. In that split second after the moment of creation, there had not been enough time forthc field to become homogeneous. This is what 1 refer to as a "chaotic" distribution of the field and it has interestingand unexpected consequences.
If the field in one region is initially almost homogeneous and is far from its equilibrium state (that is, it has a large potential energy) then it "rolls down" Hnto the minimum very slowly. But as the Universe expands, the energy density of all the particles in the Universe decreases very rapidly. So, the total energy density of the cooling Universe quickly becomes equal to the slowly changing potential energy of the scalar field.
According to the general theory of relativity, the rate at which the Universe expands depends on the energy density of the matter that fills the Universe. If the energy density is constant (or changes very slowly) then the equations tell us that the Universe must expand with ever increasing speed, exponentially.
This period of inflation is longer if the field started out further away from its minimum value, because it takes longer to roll down to the minimum. The simplest theories of the scalar field suggest that during the exponential expansion the size of the Universe was blown up by a factor of 10"ш"°", and that the largest domain must have grown from the region originally filled with the field that was in a state furthest away from its equilibrium value.
When the field rolls down to its minimum value it oscillates to and fro about the minimum and energy from the oscillating field is converted into elementary particles. By the time the oscillation has damped itself out, the Universe (or a particular domain) has been filled with hot particles and the subsequent evolution of that domain can be described adequately by the standard model of the hot big bang. The only difference is that there was a phase of exponential expansion inflating a tiny seed of the Universe by a factor of I u1000000, before the outburst from the hot big bang itself. But this small difference leads to very important consequences.
Suppose, for example, that the exponentially expanding domain started out very curved. After expanding 10100""0" times, however, the geometry of space inside such a domain scarcely differs from the Euclidean geometry of flat space, just as the surface of a balloon expanded by a similaramount would look very much like the surface of a flat plane. Similarly, any irregularities are smoothed away by the expansion (inflation) so that the domain becomes very homogeneous and isotropic. Imagine how flat and smooth even the Himalayas would seem if the radius of the Earth grew to 101"""""" times its present size.
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