Translate the following sentences. 6. Insert the suitable linking word: though  still  despite  yet

1. Robert Oppenheimer did not make any reference to Zwicky’s work even though Zwicky had been working for years on the same problem  in the same building.

2. Babbage’s Difference machine No.1 was a tremendously ambitious project. No calculator had ever worked with numbers bigger than four digits, yet Babbage planned to build a machine that could handle numbers of up to fifty.

3. Scientists have not yet come up with the explanation why many laws hold, nevertheless they do.

4. Although his friends petitioned for him Lavoisier was guillotined on 8 May 1794..

5. Yet for all this progress, no one knew just what an element was – and no one had thought to connect them with atoms in any way.

6. These ideas were revolutionary, and thus neutron stars wouldn’t be confirmed for thirty-four years.

7. As a woman she was barred from higher education in her native Poland, and so she planned to go to the Sorbonne in Paris.

8.  Scientists of Renaissance turned to Arabian mathematicians so that Archimedes’ work could be translated.

9. This crucial insight not only helped Lavoisier prove the true nature of combustion, but still underpins all experiments with matter even today.

 

6. Insert the suitable linking word: though  still  despite  yet

1. … (1)  we may find much to agree with the philosopher Ludwig Wittgenstein’s condemnation of the worship of science and the lionization of scientists, …(2) there is a lot to admire in the scientific point of view and in the character of many leading scientists.

2. Mendel received a polite hearing from the audience, … (3) no one present appeared to acknowledge that his discoveries broke a new ground.…

3.…(4) the society published Mendel’s paper ‘Experiments with plant Hybrates’ in 1866 and sent it to all major libraries in Europe and America, hardly any scientist wrote to him. … (5) a wider audience his work...(6) had little impact.

4. Charles Darwin was unsentimental enough to formulate a theory of evolution as revolutionary as any that has … (7) upset the world, even … (8) he owned an enormously warm-hearted love to nature.

 

Convert the following sentences into simple ones using verbal structures.

Example: Although Descartes’ vortex theory of the solar system was celebrated,  it was ultimately unsuccessful.  Despite being celebrated Descartes’ vortex theory of the solar system was unsuccessful.

 

1. Marie Curie spent a lot of effort and time, so that she could isolate radium.

2. Although the story about the apple is often dismissed as a legend Newton himself claimed it was so.

3. Although Darwin’s ideas grew by slow accumulation, there was one ‘Eureka!’ moment, when he read An Essay on the Principle of Population by T.Malthus.

4. The astrophysicists did everything so that the hiss would disappear.

5. Though Penzias and Wilson did  not understood the significance of their discovery they received the 1978 Nobel Prize in physics.

 

8. It’s interesting to know   Famous Research Observatories

 

· Royal Greenwich Observatory was established in 1675 at Greenwich near London. Its many famous directors, “astronomers royal” included J. Flamstead, E. Halley and G. Airy. The original Observatory building designed by Sir C. Wren is now a museum. The Observatory was moved to Succex in 1948-1957, thus it is no longer situated on the Greenwich meridian, the international zero of longitude.

· Before and after the war, Hubble played a central role in the design and construction of Mt. Wilson and Palomar Observatories in California. Completed in 1948, they were renamed in 1970 the Hale observatories for George Hale who discovered magnetic fields of sunspots. The 5, 08 m Hale telescope remained the largest telescope on Earth for the next 40 years. Hubble had the honor of being the first to use it. Asked by a reporter what he expected to find, Hubble replied: “We hope to find something that we hadn’t expected.”

UNIT 20 BLACK HOLES

1. Read the text and give it a title:

  The notion of black hole, a gravitational field so strong that it literally tears a hole in space has been around since I798 when French physicist Pierre Laplace discussed the phenomenon in the theoretical framework of Newton's mechanics and gravity. Shortly after Albert Einstein for­mulated his general relativity theory in 1916, the German astrophysicist Karl Schwartzschild reformulated the phenomenon in terms of this new theory of gravity. Real interest in black holes was generally lacking, however, until the late 1960s when astronomical observations of pulsars (rotating neutron stars) showed that black holes might indeed exist in nature and not just in our theoretical constructs.

Perhaps the easiest way to imagine a black hole is to consider (as Laplace did) the escape velocity, v_е – the velocity one body needs to escape from the gravitational field of another. Newtonian physics shows that for a special planet mass m and radius r, v_е =\/2Gm/r, where G is the universal gravitational constant. For earth v_е = 11.2 km/s (about 7 ml/s). For example, this is the speed, which rockets need to break the bonds of earth’s gravity. As either the mass increases or the radius decreases, the escape velocity increases; it has a limit, though – the speed of light, c. When the escape velocity equals the speed of light we have a black hole. Note that the radius r_S, of the black hole depends only on its mass, r_S=2Gm/c², called the Schwartzschild radius. Using r_S, in the expression for escape velocity, and setting this velocity to c, we see that the sun would become a black hole if it were shrunk to a diameter of 6 km. The earth would be a black hole if it were about 2 cm in diameter instead of 13,000 km. Since the escape velocity at the Schwartzschild radius equals the speed of light, nothing, not even light can escape the strong gravity and, for this reason, we call the object a black hole. No information about what is inside the black hole can ever come out; all we know of what's inside is the mass, not what the mass consists of (e.g., matter, anti-matter, or the type of particles that make up the matter). Actually there are two more pieces of information about the black hole that we can know; these are its electric charge and its angular momentum. Otherwise we have no knowledge of its interior.

Black holes are thought to form in nature when a star of at least about 30 solar masses finishes its nuclear burning. No outward pressure mechanism is able to overcome the inward gravitational pull and much of the core of the star–probably at least 2 to 5 solar masses – collapses into a black hole while most of the outer parts of the star get blown into space in a supernova explosion.

Note: escape velocity – вторая космическая скорость; angular momentum – момент импульса; event horizon – горизонт событий; distortion of space-time – возмущение пространства и времени; temporal dimension – временная составляющая

2. Find in the text equivalents to the phrases:

- в рамках Ньютоновской теории механики и гравитации;

- общая теория относительности;

- преодолеть земное притяжение;

- полагая скорость равной с;

- солнце стало бы черной дырой;

- пространство-время вблизи черной дыры сильно возмущено;

- пространство разорвано;

- влияние на временную составляющую пространства-времени

 

3. Give nouns corresponding to the following words:

to attract, to repel, to equal, to distort, relative, gravitational, to escape, to approach, to observe, to illustrate, to inform, accelerate, angular, to guess, to explode, nuclear, to emit.

 

4. Match the words from the top line with their antonyms from the bottom line:

 

1) to attract; 2) to increase; 3) to expand; 4) to divide; 5) to subtract; 6) to freeze;

7) to condense; 8) to accelerate; 9) to acquire; 10) to construct; 11) to absorb

 

a) to decelerate; b) to lose; c) to contract; d) to release; e) to melt; f) to destroy;

g) to evaporate; h) to decrease; i) to repel; j) to add; k) to multiply

 

4. Translate the following words and phrases into Russian:

 

to neglect,  negligible,    negligibly small;

to repel,   the force of repulsion,     to experience the force of repulsion;

to accelerate,  acceleration,      free-fall acceleration.

to weigh, weight, weightless, weightlessness; to experience weightlessness;

TALKING POINT

5. Discuss in pairs and make up a dialogue:

· the appearance of a black hole notion;

· who introduced the notion of a black hole;

· the available information about black holes;

· the reformulation of the phenomenon of a black hole in terms of the new general theory of relativity.

VOCABULARY STUDY

6. Complete the sentences using the words from the box:

a) luminosity b) mass    c) evolution   d) event horizon    e) cluster f) exotica gravity h ) supermassive black holes g) fuel i) growth

 

 

  When a star runs out of nuclear … (1), it will collapse. If the core, or central region of the star, has a … (2) that is greater than three suns, no known nuclear forces can prevent the core from forming a black hole.

Anything that comes within a certain distance of the black hole, called the … (3), cannot escape, not even light. The radius of the event horizon (proportional to the mass) is very small, only 30 kilometers for a non-spinning black hole with the mass of the sun. The extreme … (4) around black holes will produce X-rays when infalling gas is heated to millions of degrees. The best places to look for black holes are regions where large supplies of gas are available, such as double star systems, star forming regions, or the centers of galaxies.

There is strong evidence for two types of black holes: stellar black holes with masses of a dozen suns, and … (5) with masses of many millions of suns. Stellar black holes are formed as a natural consequence of the … (6) of massive stars. The origin of supermassive black holes is a mystery. They are found only in the centers of galaxies. It is not known whether they are formed in the initial collapse of the gas cloud that formed the galaxy, or from the gradual growth of a stellar mass black hole, or from the merger of a centrally located … (7) of black holes, or by some other mechanism.

The mass of a stellar black hole can be deduced by observing the orbital acceleration of a star as it .orbits its unseen companion. Likewise, the mass of a supermassive black hole can be determined by using the orbital acceleration of gas clouds swirling around the central black hole. When orbital acceleration cannot be used to establish the mass of a black hole, astronomers can place a lower limit on its mass by measuring the X-ray … (8) due to matter falling into a black hole. The pressure of the X-rays must be less than the pull of the black hole’s gravity. In the case of the black hole discovered in M82 this limits its mass to greater than 500 suns. The M82 black hole is much larger than known stellar black holes, and much smaller than supermassive black holes, thus it is called a "mid-mass" black hole.

Astrophysicists believe that galactic centers were the “only places where conditions were right for the formation and … (9) of large or very large black holes”. The discovery of a large, mid-mass black hole away from the galaxy's center shows that somehow – and it is not an easy task theoretically – black holes much more massive than ordinary stellar black holes can form in dense star clusters. Current possible explanations for the formation of mid-mass black holes include such … (10) as black hole mergers or the collapse of a hyperstar. An intriguing implication is that mid-mass black holes could prove to be a common feature in star forming regions of galaxies.

Note: merger – поглощение; luminosity – светимость; implication – вывод, следствие.

 

WORD FORMATION

7. Use the words in brackets in the right form:

Space-time in the vicinity of a black hole is … 1 (severe) distorted, so much so that time is stopped and space is ripped open, for we can't cross the radius successfully. The effects on the temporal dimension of space-time can be… 2 (illustrate) by considering a journey into a black hole. You and your robot (the one who'll make the journey which you … 3 (observation) from afar) synchronize your watches before beginning: you monitor the jour­ney on your robot's watch, which you see through your telescope. As your robot falls toward the black hole you notice that the light emitted by its watch is … 4 (redshift) – it appears more red than it did before the robot left. This occurs not only because it is … 5 (accelerate) to high speeds as it falls in but also because the intense … 6 (gravitation) field induces a redshift on the light. Even if the robot were to somehow stop in its tracks, the light from it would be redshifted by the gravity. Furthermore the time from its clock, as read by you, is earlier than what is given by your watch. In other words, time for the robot has slowed down as you see it. As it gets … 7(close) to the black hole the slowdown is greater, so much so that, if noon were the time you calculated that the robot would reach the Schwartzschild radius, then you would see its watch approach noon but never reach it, just as you would notice the robot approach the Schwartzschild radius but never get there.

  For the robot things are different: as −it falls toward the black hole it notices the horizon (the boundary of the black hole as … 8 (observe) by the robot) to rise up into the sky and shrink into a smaller and smaller circle overhead until it finally … 9 (vanish) when the robot reaches the Schwartzschild radius (when its clock reads noontime). Now the robot sees noth­ing of the outside world; for this reason the Schwartzschild radius is also called the "event horizon." What happens inside the black hole is anybody's guess and is not properly describable by someone outside. Perhaps the robot falls immediately to the center and is crushed by the infinite gravity, perhaps it comes out into another universe where robots aren't … 10 (subject) to such cruel and unusual experimentation; perhaps something else. Notice that you, on the outside, never see the robot pass the Schwartzschild radius – just approach it – but the robot notices that it fell in; this is an example of the severe distortion of space-time, quite literally a hole in space.

8. Write a summary in English to the text below:

Великий ученый Альберт Эйнштейн в общей теории относительности доказал возможность существования черных дыр. И хотя они еще до сих пор не обнаружены, есть факты, подтверждающие эту гипотезу. Звезды  находятся в постоянном развитии. Постепенно термоядерное топливо (thermonuclear fual) в них выгорает и звезда "стареет". Чем больше масса звезды, тем короче ее жизнь и тем быстрее она становится красным гигантом, а затем может превратиться в белый карлик(a white dwarf) и очень медленно остывать. Под действием гравитационного поля  эта звезда может сжаться до ядерной плотности, став нейтронной звездой, или же взорваться, как сверхновая, или же стать звездой-невидимкой под названием "черная дыра".

Из теории относительности Эйнштейна существование этих необычных объектов следует с неизбежностью. Силы тяготения связаны с физическими свойствами самого пространства. Оказывается, любое тело не просто существует в пространстве само по себе, но изменяет вокруг себя его геометрию.

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