Материал: Гвоздева Пхысицс фор адванцед студентс 2011
engines work, but to understand how microchips and supernovas work. The word ‘explain’ is important here. Not just ‘predict’. Prediction is a characteristic of a scientific theory, but it is not the most important one, the most important one is explanation. A fundamental theory is needed in the explanation of many diverse things. The more and more diverse phenomena the theory can explain, the more fundamental it is.
−Now the second question: What constitutes a universal computer?
−It’s not perhaps obvious to a lay man that all existing computers, the one you have on your desk, the supercomputer that the National Security Agency uses and so on are completely identical to each other. They differ only in speed and memory capacity. That property is called universality. Alan Turing was the first person to postulate a universal computing machine. My innovation was to redo his work using explicitly quantum physics instead of implicitly classical physics.
−Is it difficult to move from tackling fundamental questions about the universe to tackling fundamental questions about computers?
−There is to be a link. I am neither particularly interested in making new and better kinds of computers, nor in understanding the theory of computation. What I want to work on is what is fundamental: to understand the important issues of the foundations of physics, what quantum theory means, what it is telling us about the structure of reality, and so on.
But it turns out that to understand the important issues of the foundations of physics one has to express the laws of physics and explanations of physical processes in terms of computation and information flow.
Any type of experiment you can think of doing is information processing. The structure of the universe is based on information flow. The computation theory implemented in the deepest-known physical laws is the best formalism and language for understanding physical reality. I mean the quantum theory of computation. Quantum mechanics is the deepest knowledge known to science. It describes the activity of subatomic particles and deals with very small scales.
Vocabulary Notes
1. an issue – an important subject that people are discussing or arguing about
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2.diverse – various
3.a lay man – a nonprofessional
4.to process information is to put it through a computer system in order to deal with it.
5.to implement – to realize – to carry out
POST-READING TASK
(To be done at home in writing)
I. Pick up the information concerning David Deutsch and write it out making necessary changes.
E.g. Throughout his research career he has been interested in the most fundamental issues.
II. Complete the sentences.
1.Quantum mechanics … the deepest knowledge ….
2.A fundamental idea … one which ….. ..in the understanding of many other ideas.
3.The laws of thermodynamics … fundamental laws.
4.A fundamental idea …. in the explanation of many …. things.
5.Any experiment … information processing.
6.The structure of the universe … on the information flow
7.The computation theory implemented in …… is the best formalism and language for understanding …..
8.Quantum mechanics …. the activity of subatomic particles.
9.Quantum mechanics …. .. very small scales.
III. Run through the passage. Innumerate the changes quantum mechanics has brought about.
Quantum mechanics has brought about a number of changes in our thinking about the world. First, the world is no longer tightly deterministic and mechanical; there is a probabilistic character to physical processes. And, of course, quantum theory also has its own relational character. Once two quantum entities interact with each other, they retain a very surprising power to influence each other, however far they are separate. Quantum theory also tells us that the world is not simply objective; It is something more subtle than that. In some sense it is not obvious for us, but it has a structure that we can understand.
John Polkinghorne
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Vocabulary Notes
1.an entity – a complete separate thing that is not divided
2.to retain – to continue to keep
3.subtle – not completely obvious – veiled
CLASS EXERCISES
Exercise 1 (in groups)
Checking up understanding
1.What is a fundamental idea?
2.Could you give an example of a fundamental idea?
3.What fundamental issues does David Deutsch want to understand?
4.Why does David Deutsch study the theory of computation, although he is interested in fundamental ideas?
5.What is an experiment according to David Deutsch?
6.What is the structure of the universe based on?
7.What is the best formalism for understanding physical reality?
Exercise 2 (in pairs)
Exchange the information about David Deutsch.
Exercise 3 (do it yourself)
Translate the sentences, then compare your variant of translation with the original sentences and make corrections, if any.
1.Меня всегда интересовали фундаментальные вопросы.
2.Я начал заниматься квантовой механикой потому, что квантовая механика – самое глубокое знание, которым располагает наука.
3.Я работал над проблемой гравитации квантового поля и над теорией квантовых измерений.
4.Фундаментальная идея – это такая идея, которая необходима для понимания многих других идей.
5.Меня не особенно интересует создание новых компьютеров, меня не особенно интересует сама теория вычислений.
6.Я хочу понять важные вопросы мироздания и то, как можно объяснить мироздание, понимая законы квантовой механики.
7.Оказывается, чтобы понять квантовую механику нужно выражать физические законы на основании потока информации.
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UNIT 12
THE STUFF OF WHICH THE UNIVERSE IS MADE
“The universe at the bottom displays a combination of pure numbers.”
Pythagoras
Note
We used to think – We thought so, but no longer think so.
PRE-READING TASK Study a grammar point.
I. The Complex Object – дополнительное придаточное предложение
consider (believe, suppose, assume, expect) may be followed by this structure:
O (object) + to V (be V3) = Russian – считаю, что; полагаю,
что; допускаю, что
Study the sentence.
There are many more faint sources than strong ones. On average, one would expect the faint sources to be the more distant ones.
We use both variants.
Study the sentences.
1.The Pythagoreans considered that numbers were the very stuff of which the universe was made.
2.The Pythagoreans considered numbers to be the very stuff of which the universe was made.
1.Scientists believe that the universe is governed by well-defined
laws.
2.Scientists believe the universe to be governed by well-defined
laws.
Give Russian correspondence:
to be due to (to be caused by; to be a direct result of, to result from), in fact (really, actually), actually (really), actual (real), according to (in the opinion of), moreover (more than that), any, for (as, since); either … or, unless (if not)
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LOGOS
RELATIONSHIP OF NUMBERS
“We thought that if we know one, we know two because one and one is two. Now we know that we have to learn a great deal about ‘and’.
Edenton
Study the passage. Mind the underlined grammar.
On the atomic scale our ordinary ideas of cause and effect have no meaning. It may be as Einstein thought that this is due to our ignorance of nature and the time may come when we have explanation. But at present it has not been achieved and in the opinion of many mathematical physicists any laws are impossible here. In the world of atoms and radiation the old rigid determination has gone. All we find is a flux of matter and energy which is amenable to calculations. In fact we have a return to the Pythagoras’ view that the universe at the bottom displays the combination of pure numbers.
The Pythagoreans considered numbers to be the stuff of which the universe was made. According to the Pythagoreans number 1 represented a point, two a line, three a surface and four a solid. Out of numbers one, two, three, four they could construct a world. They discovered many extraordinary relations about numbers and geometrical figures. They considered the relationships between numbers and geometrical figures to be built into the foundation of the universe. According to the Pythagoreans the mean proportionals (logos) do more than articulate the intervals; they considered them to be the actual bond which holds together the unrelated elements of reality and welds them into a whole.
Edenton attempted to derive the properties of elementary particles of matter from the consideration of pure numbers. He believed the universe to be fundamentally a mathematical construction. He wrote “The nature of number is able to give guidance and teaching to every man in what is puzzling and unknown. None of the existing things would be clear to anyone, either in them or in their relationship to one another unless there existed Number and its essence.
J.Butler, professor of Chemical Physics in the University of London
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