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Гвоздева Тхе Цосмос 2011

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CLASS EXERCISES

Exercise 1 (in groups)

Checking up understanding

1.What does the expansion of the universe mean?

2.Is this expansion smooth or chaotic?

3.What is background microwave radiation?

4.What are some flecks on the TV screen due to?

5.How can one describe the expansion of the universe?

6.Why can one describe the expansion of the universe in terms of a single number?

7.How does the gravitational attraction affect the rate of the expan-

sion?

8.In what case will gravitational attraction eventually stop the expansion?

9.How would the universe behave in this case?

10.What would the big crunch be like?

11.What is a singularity?

12.What is the crucial question for the future of the universe?

13.How would the universe behave in case the average density of the universe is less than the critical value?

14.How would the universe behave in case the average density of the universe is greater than the critical value?

Exercise 2 (do it yourself)

Translate the parts of sentences using One as the subject + a modal verb (can, can’t, should, have to, needn’t).

1.Можно описать расширение вселенной на основании одного числа расстояния между двумя галактиками.

2.Можно предположить

3.Можно увеличить

4.Можно замедлить

5.Можно сжать

6.Можно расширить

7.Можно предсказать

8.Можно сделать вывод (to conclude)

9.Нужно объяснить

10.Можно подумать

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11.Нужно быть очень осторожным (to be careful)

12.Можно начертить график скорости галактик в зависимости от их яркости (to plot a graph of something against something).

13.Нельзя терять надежду.

Exercise 3 (do it yourself)

Translate the sentences. Then check up your translation against the original sentences in the passage and correct your mistakes, if any.

1.Расширение вселенной можно описать на основании расстояния между двумя галактиками.

2.В настоящее время это расстояние увеличивается.

3.Но можно предположить, что силы притяжения между галактиками будут замедлять скорость расширения.

4.Сингулярность – это звезда с бесконечной величиной плотности, при которой законы физики не действуют.

5.У меня есть определенные преимущества перед другими пророками.

UNIT 6

ON THE DARK MATTER

“As much as 90 percent of the matter in the universe is invisible. Detecting dark matter will help astronomers better comprehend the universe’s destiny.”

Vera Rubin

PRE - READING TASK Study some grammar points.

I. Modal verbs show the attitude of the speaker to the idea he expresses.

We use must + Vo to say we are sure that something is true for the present or the future = most probably.

Study the sentences.

1.The universe must contain the dark matter, which we cannot observe directly.

2.There must be some unseen form of matter.

3.There must be extra dark matter present in clusters of galaxies.

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4. The universe must contain enough dark matter to bring the density up to the critical density.

II. We use special tenses with if when we are talking about imaginary situations.

To talk about imaginary present or future situations we use:

If S + V2, S + would + Vo

Study the sentences.

1.Collections of stars and gas would fly apart if they contained only the stars and gas that we observe directly.

2.The speeds at which individual galaxies are moving in the clusters are so high that the clusters would fly apart, unless they were held by gravitational attraction.

III. The participle

The English verb changes in four forms:

I II III

to estimate (the infinitive) estimated (the past simple) estimated

(the passive participle)

IV

 

estimating (the active participle)

N + Ving or Ved clause определительное придаточное предло-

жение (Russian который).

Study the sentences.

1.Not all the scientists working in this field share this idea.

2.The speed of a pulse of light is the distance it travels between two events, divided by the time interval between the events.

3.A shock wave, called Cerenkov radiation, can be detected from the ground as a flash of visible light.

4.One can draw a graph showing the amount of light elements vertically and the amount of normal matter in the universe along the horizontal axis.

5.The Dirac equation, as Dirac himself pointed out, was the basis of most of physics and all chemistry. However, we have been able to solve the equation only for the very simplest system, the hydrogen atom, consisting of one proton and one electron.

Note:

N + V3 (the past participle)

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We do not always put participles as adjectives before nouns. It is not always easy to explain why one participle can be used before a noun but another one cannot.

Study the sentences.

1.The mass required is considerably greater than the masses of all the galaxies.

2.The rate needed was very low.

3.The heat released generates a pressure that enables the sun to resist the attraction of its own gravity.

IV. S + is supposed (is considered, is believed, is supposed, is expected, is assumed) + toV. These verbs express generally accepted opi-

nion and correspond to Russian – Считают, что; Полагают, что;

Ожидают, что; Допускают, что

Study the sentences.

1.General relativity can’t be considered to be a complete theory.

2.The so-called missing matter is believed (is considered, is supposed, is assumed) to reside within clusters of galaxies.

3.The neutrino was believed to have no mass of its own, but some recent observations have suggested that the neutrino may have a small mass.

We use two variants. Study the sentences.

1.It was found that the nucleus was composed of the so-called ele-

mentary particles.

2. The nucleus was found to be composed of the so-called elementary particles.

1.It was considered that Democritus had a universal mind.

2.Democritus was considered to have a universal mind.

1.It was believed that everything was composed of indivisible and indestructible atoms.

2.Everything was believed to be composed of indivisible and indestructible atoms.

V. Would is used to talk about the natural course and behavior of things and events as a result of some action. It is the less definite form of will.

Study the sentences.

1. A lighter planet would have a smaller escape velocity than a more massive one.

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2. The white hole could be in another part of the universe. This would offer the possibility of rapid intergalactic travel.

Give Russian correspondence:

unless (if not), from (on the basis of), even if, directly (here - with a telescope), as (here - while), considerably greater (much greater), another (a second), unless (if not), a few (some, several), it follows, therefore (so, thus), specific (particular, specified), close to something (near something), the only (single), a way (a method, a technique), actually (really), an effect (an influence)

UNSEEN FORM OF MATTER

Study the passage. Translate the sentences marked with asterisks in writing.

We can try to estimate the average density of the universe from observations. If you count the stars that we can see and add up their masses, we get less than one per cent of the critical density. Even if we add in the masses of the clouds of gas that we observe in the universe, the total still makes up only about one per cent of the critical value.

We know, however, that the universe must also contain what is called the dark matter, which we cannot observe directly. One piece of evidence comes from the spiral galaxies. These are enormous pancakeshaped collections of stars and gas. We observe that they are rotating about their centres, but the rate of rotation is so high that they would fly apart if they contained only the stars and gas that we observe directly. *There must be some unseen form of gravitational attraction whose matter is great enough to hold the galaxies together as they rotate.*

Another piece of evidence for dark matter comes from clusters of galaxies. We observe that galaxies are not uniformly distributed throughout space; they are gathered together in clusters that range from a few galaxies to millions. Presumably these clusters are formed because the galaxies attract each other into groups. However, we can measure the speeds at which individual galaxies are moving in these clusters. *We find they are so high that the clusters would fly apart unless they were held together by gravitational attraction. The mass required is considerably greater than the masses of all the galaxies. It fol-

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lows, therefore, that there must be extra dark matter present in clusters of galaxies.* So, the only way we can detect dark matter would be by its effect on bright matter.

The main candidates of dark matter would be remnants left over from the early stages of the universe. One possibility is elementary particles. There are several hypothetical candidates, particles which we think might exist but we haven’t actually detected them yet. But the most promising case is a particle for which we have good evidence, the neutrino. The neutrino was thought to have no mass of its own, but observations have suggested that the neutrino may have a small mass. *If this is confirmed and is found to be of right value, neutrinos would provide enough mass to bring the density of the universe up to the critical value.*

Vocabulary Notes

1 to estimate – to calculate

2 to add up – if you add up several numbers, you calculate their total 3 to add in – if you add in something, you include it as a part of

something else

4 the total – the number that you get when you add a series of figures together

5 enormous – very large

6 presumably – most probably

7 to require – to need

8 extra – additional

9 a remnant – a small part that was left of what was destroyed

10 promising – perspective

11 to confirm – to prove

POST-READING TASK (to be done in writing)

I. Put in the prepositions.

1.We can try to estimate the average density … the universe … observations.

2.One piece … evidence … dark matter comes …the spiral galaxies.

3.These are enormous pan-shaped collections … stars and gas.

4.They are rotating … the centres.

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5.Another piece … evidence … dark matter comes … clusters of galaxies.

6.Galaxies are not uniformly distributed … space.

7.Clusters … galaxies range … a few galaxies … millions.

8.We can measure the speed … which the individual galaxies are moving.

II. Study grammar point III and do an exercise. Change the sentences according to the model:

S + (is believed; is supposed; is expected; is considered; is known; is proved) + to V

1.The universe must contain some matter which we cannot observe directly.

2.One piece of evidence comes from spiral galaxies.

3.Spiral galaxies are enormous pancake-shaped collections of stars and gas.

4.Another piece of evidence for dark matter comes from clusters of galaxies.

5.The speeds at which individual galaxies are moving are so high that the clusters would fly apart unless they were held together by gravitational attraction.

6.The mass required is considerably greater than the masses of all the galaxies.

7.The main candidates of dark matter are elementary particles.

8.The neutrino is the most promising candidate.

III. A paragraph is a micro text. Cut down each paragraph of the passage to the topical sentence and write a summary.

IV. Do you have any information about the dark matter which is not given in the passage? Write a paragraph.

CLASS EXERCISES

Exercise 1 (do it yourself)

Make up simple sentences using the below words and expressions. Follow the passage.

1.to contain dark matter

2.to observe dark matter directly

3.an enormous pan-shaped collection of stars and gas

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4.to rotate about its centre

5.to be uniformly distributed throughout space

6.to be gathered together in clusters

7.to range from to

8.to detect dark matter

9.to suggest

10.to bring up to

Exercise 2

Sharing ideas (in groups)

1 How can we estimate the average density of the universe?

2.Where do the pieces of evidence of dark matter come from?

3.What is a spiral galaxy?

4.How do astronomers account for the fact that the spiral galaxies do not fall apart as they rotate?

5.How are galaxies distributed throughout space?

6.How many galaxies are there in a cluster?

7.What mechanism collects stars in clusters?

8.At what speed are individual galaxies moving in these clusters?

9.Why do the clusters not fall apart?

10.What is the proportion between the mass of all the galaxies and the mass required for the galaxies to form clusters?

11.Why do astronomers call extra matter ‘dark matter’?

UNIT 7

BLACK HOLES

“Turn to Stephen Hawking if you would look outward, to the ends of the universe”

Independent on Sunday

PRE-READING TASK Study some grammar points. I. N + to Vo; N + to be V3

An infinitive after a noun characterizes it and expresses an action which must be done or could be done in the future.

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Study the sentences.

1.The universe is a puzzle to be guessed.

2.This is a much more difficult question to answer.

3.Because my father was a scientific researcher, I felt that scientific research was a natural thing to do when one grew up.

II. Active and Passive

A verb has two categories: tense (past, present and future) and voice (active and passive). There are two infinitives:

active to V and passive to be + V3.

On the basis of an active infinitive we form active sentences and use active when it is important who or what does the action.

On the basis of a passive infinitive we form passive sentences and prefer passive when it is not important who or what does the action.

In passive sentences we use be (is, are, was, were, has been, will be etc) + V3.

Study the sentences.

1.In the 1930s quantum mechanics was applied with great success to systems such as atoms or molecules, which have only a finite number of degrees of freedom.

2.The problem has been overcome.

3.The interactions are divided into four categories and are represented by integer-spin fields.

Note: In passive sentences modal verbs are followed by be + V3

Study the sentences.

1.I want to discuss the possibility that the goal of theoretical physics might be achieved in the not-too-distant future.

2.The values of these quantities cannot be predicted by our theories. Instead, they have to be chosen to agree with observations.

III. Would

a.Would is used to talk about the natural course and behavior of things and events as a result of some action. It is the less definite form of will.

Study the sentence.

If the electrons are in orbit around the nucleus, electromagnetic waves would carry away energy and would cause the electrons to spiral into the nucleus.

b.We also use would, if we imagine the situation. We can also use could = would be able to

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Study the sentence.

In this state the electron couldn’t radiate energy in the form of electromagnetic waves because there would be no lower energy state.

IV We use that (those) to refer to a thing (things) that has been mentioned before.

Study the sentences.

1.The key physical properties of Mars are remarkably similar to those of Earth.

2.The Mar’s axis is tilted to a similar degree as that of Earth.

3.The difference between the classical physics and the modern one is that between logical and illogical physics.

Give Russian correspondence:

as (in the process), eventually (finally), both ….. and, an effect (an influence), then (in this case), until, a few (some), so (thus, therefore, hence), fails to V (is unable to V)

Study the passage.

As far as I know, the first person to discuss black holes was a Cambridge man called John Mitchell, who wrote a paper about them in 1783. His idea was this. Suppose you fire a cannon-ball vertically upwards from the surface of the earth. As it goes up, it will be slowed down by the effect of gravity. Eventually, it will stop going up and will fall back to the earth. If it started with more than a certain critical speed, however, it would never stop rising but would continue to move away. This critical speed is called the escape velocity. It is about 7 miles a second for the earth, and about 100 miles a second for the sun. These velocities are greater than the speed of a real cannon-ball, but they are much smaller than the velocity of light, which is 186,000 miles a second. This means that gravity does not have much effect on light; light can escape without difficulty from the earth or the sun. However, Mitchell reasoned that it would be possible to have a star that was both massive and small in size so that its escape velocity would be greater than that of light. We would not be able to see such a star because light from its surface would not reach us; it would be dragged back by the star’s gravitational field. However, we might be able to detect the presence of the star by the effect that its gravitational field would have on nearby matter.

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