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.
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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.