Гвоздева Пхысицс фор адванцед студентс 2011
.pdf3.According to the General Theory of Relativity the laws are the same for someone standing in one place.
4.Observers moving at different velocities measure different time intervals between the same pair of events.
Note:
You translate the past participle V3 without any words referring to it
before you translate a N.
Study the sentences.
1.The number of particles emitted decreased.
2.The energy released is in the order of one electron volt per atom.
3.The mass required is considerably greater than the masses of all galaxies.
III. We use to V to talk about the purpose of doing something (why someone does something). We can also use in order to V to talk about the purpose.
Study the sentences.
1.We used new mathematical calculation techniques to show that there was a state of infinite density in the past.
2.To see where a particle is, you have to shine light on it.
3.In order to escape from a black hole, you would have to travel faster than light.
4.In order to discuss the beginning of the universe, we need a theory that combines general relativity with quantum mechanics.
IV. S + is supposed; is considered; is believed, is supposed; is expected; is assumed + to V. These verbs express generally accepted opinion 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.
V. One is a personal pronoun and can be used as the subject of a sentence = You. It is a formal subject. One (You) is not translated.
Study the sentences.
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1.One can plot a graph of the speed of galaxies against their brightness or magnitude.
2.The uncertainty principle of Heisenberg showed that one couldn’t measure the state of a physical system exactly. The more accurately one measures its velocity, the less accurately one can measure its position. So, one can’t predict the probabilities of different outcomes.
VI. Two negations make a sentence emphatic.
The full implications of the photoelectric effect were not realized until 1925. = только в 1925…
Study the sentences.
1.The implications of this theory for old stars and other massive bodies were not realized until the 1960’s.
2.Neutron stars were not observed until 1967.
Give Russian correspondence:
the fact that, to lead to (to result in, to give rise to), in particular (ant. in general ), in order to (to V), continuous (ant. discrete)), rather (we use rather to introduce a correction), directly (straightly), at least (the minimum amount), the more ….., the greater; thus (so, therefore, hence), as (since), times (multiplied by), that is (that is to say)
THE NECESSARY EXTRA GRADIENT
IS QUANTUM MECHANICS
FYI
A singularity is a place of infinite density. It would be the end of time. The gravitational field of a singularity would be so strong that light couldn’t escape from the region around it but would be dragged back by the gravitational field.
Study the passage. Mind the underlined grammar points.
Einstein’s general theory of relativity turned out to predict singularities, which led to a crisis in physics. The equations of general relativity, which relate the curvature of space-time with the distribution of mass and energy, cannot be defined as singularity. This means that general
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relativity cannot predict what comes out of a singularity. In particular, general relativity cannot predict how the universe should begin at the big bang. Thus, general relativity cannot be considered to be a complete theory. It needs an added ingredient in order to determine how the universe should begin and what should happen when matter collapses under its gravity.
The necessary extra ingredient seems to be quantum mechanics. In 1905 Einstein wrote about a phenomenon called the photoelectric effect. It had been observed that when light fell on certain metals, charged particles were given off. The puzzling thing about the photoelectric effect was that if the intensity of the light was reduced, the number of particles emitted decreased, but the speed with which each particle was emitted remained the same. Einstein showed that this could be explained if light came not in continuously variable amounts but rather as packets of a certain size. Einstein’s paper showed that you could directly observe individual quanta. Each particle emitted corresponded to one quantum of light hitting the metal. Einstein’s discovery won him the Nobel Prize in 1922.
The full implications of the photoelectric effect were not realized until 1925, when Heisenberg pointed out that the photoelectric effect made it impossible to measure the position of a particle exactly. To see where a particle is, you have to shine light on it. But Einstein had shown that you could not use a very small amount of light; you had to use at least one packet, or quantum. This packet of light would disturb the particle and would cause it to move at a speed in some direction. The more accurately you wanted to measure the position of the particle, the greater the energy of the packet you would have to use and thus the more it would disturb the particle. The uncertainty in the position of the particle, times the uncertainty in its speed, would always be greater than a certain minimum amount.
The uncertainty principle of Heisenberg showed that as one couldn’t measure the state of the system exactly, one couldn’t predict the probabilities of different outcomes. It was this element of chance, or randomness, that so disturbed Einstein. Einstein refused to believe that physical laws should not make a definite, unambiguous prediction for what would happen.
Einstein’s general relativity is what is called a classical theory; that is, it does not incorporate the uncertainty principle.
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Stephen Hawking
Vocabulary Notes
1.to relate something with something – to connect something with something
2.extra – additional
3.to reduce – to decrease
4.variable – changeable
5.to correspond – to be similar
6.to point out – to show
7.If something is disturbed, its shape or position is changed. If something disturbs you it makes you worry.
8.If someone refuses to do something, he doesn’t want to do it.
9.to cause – to make something do something
10.an outcome – a result
11.unambiguous – clear
POST-READING TASK
(To be done at home in writing) I. Give your interpretation.
1.The equations of general relativity
2.A crisis in physics
3.The photoelectric effect
4.The puzzling thing about the photoelectric effect
5.The Einstein’s explanation
6.The uncertainty principle of Heisenberg
II. Study grammar point I and do the exercise.
Change the sentences according to the model: S + turned out +
+to V (be V3).
1.It turned out that Einstein’s theory of relativity predicts singulari-
ties.
2.It turned out that general relativity cannot predict what comes out of a singularity.
3.It turned out that a necessary extra ingredient is quantum mechan-
ics.
4.It turned out that the quantum phenomenon and the uncertainty principle are unavoidable
5.It turned out that the number of particles emitted decreased, if the intensity of light reduced.
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6.It turned out that the speed with which each particle was emitted remained the same.
7.It turned out that light came as packets of a certain size.
8.It turned out that each particle emitted corresponded to one quantum of light hitting the metal.
CLASS EXERCISES
Exercise 1 (in groups)
Checking up understanding
1.What is a singularity?
2.What do the equations of general relativity relate the curvature of space-time with?
3.What does general relativity need in order to determine how the universe should begin?
4.What does the necessary extra ingredient seem to be?
5.For what discovery did Einstein win the Nobel Prize?
6.How much light do you have to use to see where the particle is according to Einstein?
7.Why do you have to use a quantum of light, but not a smaller amount of light?
8.What did Einstein refuse to believe?
9.Why is The General Theory of Relativity considered to be a classical theory?
Exercise 2 (class activity)
It is (was) …. that = именно It is (was) ….. who = именно Translate the sentences.
1. It is quantum mechanics that seems to be the necessary extra ingredient to determine how the universe should begin.
2 It was the German physicist Max Planck who introduced the idea of light coming in quanta.
3.It was the paper on the photoelectric effect that won Einstein the Nobel Prize.
4.It is the quantum of light that would disturb the particle and would cause it to move at a speed in some direction.
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5.It was this element of chance, or randomness, that so disturbed Einstein.
6.It was Einstein’s paper that showed that one could directly observe individual quanta.
7.It was only in 1925 that the full implications of the photoelectric effect were realized.
Exercise 3 (do it yourself)
Translate the sentences, then compare your variant with the original sentences and make corrections, if any.
1.Уравнения общей теории относительности соотносят кривизну пространства-времени с распределением массы и энергии.
2.Известно, что Большой взрыв произошел 15 миллиардов лет тому назад.
3.Квантовая механика считается самым глубоким знанием, известным науке.
4.Было установлено, что свет испускается дискретными количествами энергии определенного размера.
5.Теорию относительности считают классической теорией, так как она не включает в себя принцип неопределенности.
UNIT 10
THE QUANTUM THEORY
PRE-READING TASK Study some grammar points. I. Would
a. We use would 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.
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b. We use would if we imagine the situation. We can also use could = would be able to
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.
II. For – phrase
We use for + N + to V to talk about the purpose of doing something.
Study the sentences.
1.There would be no lower state for the electron to go to.
2.Quantum theory can be formulated as a “sum over histories.” The idea is that every particle has every possible path, or history, in spacetime. For this idea to work, one has to consider histories that take place in imaginary rather than in the real time.
3.For the idea to be formulated, it has to contain the concept of imaginary time.
Give the Russian correspondence:
the very small (the smallest), that is (that is to say), continuously (ant. discretely), at least (as a minimum), instead (rather), both …… and, in the form of
THE HEISENBERG UNCERTAINTY PRINCIPLE
AND THE MODEL OF THE ATOM
Study the passage. Mind the underlined grammar.
The general relativity theory and the Maxwell theory of electrodynamics are classical theories; that is, they involve continuously variable quantities that can, in principle at least, be measured to arbitrary accuracy. However, a problem arose when scientists tried to use such theories to construct a model of the atom.
It was discovered that the atom consists of a small, positively charged nucleus surrounded by a cloud of negatively charged electrons. The natural assumption was that the electrons were in orbit around the nucleus as the earth is in orbit around the sun. But the classical theory predicts that the electrons would radiate electromagnetic waves. These waves would carry away energy and would cause the electrons to spiral into the nucleus, producing the collapse of the atom.
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This problem was overcome by the discovery of the quantum theory, which is the greatest achievement in theoretical physics in last century. The basic postulate of this theory is the Heisenberg uncertainty principle, which states that certain pairs of quantities, such as the position and momentum of a particle, cannot be measured simultaneously with arbitrary accuracy. In the case of the atom, this meant that in its lower energy state the electron couldn’t be at rest in the nucleus because, in that case, its position would also be exactly defined (at the nucleus) and its velocity would also be exactly defined (to be zero). Instead, both position and velocity would have to be smeared out with some probability distribution around the nucleus. In this state the electron could not radiate energy in the form of electromagnetic waves because there would be no lower energy state for it to go to.
Stephen Hawking
Vocabulary Notes
1.arbitrary – approximate – not exact – random
2.an assumption – if you make an assumption, you say that something is true, although you have no proof – an idea
3.to overcome a problem – to solve it
4. simultaneously – at the same time
POST-READING TASK
(To be done at home in writing)
I. Write a digest of the passage covering the below points:
1.Formulate the problem, which arose when one tried to use classical theories to construct the model of the atom.
2.Say how the problem was overcome.
3.Characterize the importance of the quantum theory.
4.The application of the quantum theory for the interpretation of the structure of the atom.
II. Draw the model of the atom and be ready to speak about the difference in its interpretation in terms of the classical theory and the quantum theory.
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CLASS EXERCISES
Exercise 1 (in groups) Checking up understanding
1 What quantities does any classical theory involve?
2.What is a continuously variable quantity?
3.What does the atom consist of?
4.How would the electron behave in terms of the classical theory?
5.What is the greatest achievement in theoretical physics in last cen-
tury?
6.What is the basic postulate of the quantum theory?
7.What does the Heisenberg uncertainty principle state?
8.How would the electron behave in terms of the quantum theory?
Exercise 2 (do it yourself)
Translate the sentences, then compare your variant with the original sentences and make corrections, if any.
1.Общая теория относительности – классическая теория.
2.Теория электродинамики Максвелла – классическая теория.
3.Атом состоит из маленького положительного заряженного ядра, окружённого облаком отрицательно заряженных электронов.
4.Электроны находятся на орбите вокруг ядра, также как земля находится на орбите вокруг солнца.
5.Открытие квантовой теории является величайшим достижением теоретической физики прошлого века.
6.Основным постулатом квантовой теории является принцип неопределенности Гейзенберга, согласно которому нельзя одновременно измерить и положение частицы, и ее импульс.
Exercise 3 (in groups) Discussion
1 “The interpretation of the model of the atom in terms of the classical theory.”
2 “The interpretation of the atom in terms of the quantum theory.”
Each student gives contribution to the discussion. The audience is asking questions.
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UNIT 11
QUANTUM MECHANICS
“Quantum mechanics is the deepest knowledge known to science. It describes the activity of subatomic particles and deals with very small scales.”
David Deutsch
PREREADING TASK
Give Russian correspondence:
to bring about (to cause), a number of (a range of, a set of) no longer (no more), once (as soon as), in some sense (true according to one of the interpretations), for instance (for example), the more … the more, neither …. nor, particularly (especially), it turns out, in terms of (in a particular language), any
QUANTUM COMPUTATION
Interview with Dr. David Deutsch, a theoretical physicist of the Centre for Quantum Computation at the University of Oxford
−How did you start working on quantum theory?
−Throughout my research career I have been interested in the most fundamental issues. I got into quantum mechanics because it is the deepest knowledge known to science. I did various kinds of work on quantum field theory, in the hope of making progress on quantum gravity. I worked on quantum measurement theory and so became an advocate of the many-universe interpretation. I saw there was a need to extend the idea of Alan Turing of a universal computer by using quantummechanical physics. And I did that: I proposed the universal quantum computer and proved it was universal. I showed it had properties that no existing computer had.
−That raises two questions. First, how do you define fundamen-
tal?
−A fundamental idea is the one which is needed in the understanding of many other ideas. For instance, the laws of thermodynamics are fundamental laws. You don’t just need them to understand how steam
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