Can you imagine that our universe was smaller than an atom
Can you imagine that our universe was smaller than an atom
Can you imagine that our universe was smaller than an atom
B4
50 years ago people even did not hear / didn’t hear of computers, and today we cannot imagine life without them. Computer technology is the fastest-growing industry in the world.
NOT HEAR
B5
The first computer was the size of a minibus and weighed a ton.
BE
B6
Today, its job can be done by a chip the size of a pin head. And the revolution is still going on.
DO
B7
The next generation of computers will be able to talk and even think for themselves. Of course, they’ll be a lot simpler than human brains, but it will be a great step forward. Such computers will help to diagnose illnesses, find minerals, identify criminals and control space travel.
BE ABLE
B8
Some people say that computers are dangerous, but I do not agree / don’t agree with them. They save a lot of time. They seldom make mistakes.
NOT AGREE
B9
It’s much easier to surf the Internet than to go to the library.
EASY
B10
On-line shopping makes it possible to find exactly what you want, saving both time and money.
MAKE
B11
E-mail is a great invention, too. It’s faster than sending a letter and cheaper than sending a telegram.
BE
B12
All in all, I strongly believe that computers are a useful tool. They have changed our life for the better. So why shouldn’t we make them work to our advantage?
CHANGE
The quantum world is mind-bogglingly weird
No matter how hard physicists probe, they still puzzle over this, the universe’s deepest secret
The quantum world is the world that’s smaller than an atom. Things at this scale don’t behave the same way as objects on the scale that we can see.
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September 14, 2017 at 6:16 am
If you’re interested in the smallest things known to scientists, there’s something you should know. They are extraordinarily ill-behaved. But that’s to be expected. Their home is the quantum world.
Explainer: Quantum is the world of the super small
These subatomic bits of matter don’t follow the same rules as objects that we can see, feel or hold. These entities are ghostly and strange. Sometimes, they behave like clumps of matter. Think of them as subatomic baseballs. They also can spread out as waves, like ripples on a pond.
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Although they might be found anywhere, the certainty of finding one of these particles in any particular place is zero. Scientists can predict where they might be — yet they never know where they are. (That’s different than, say, a baseball. If you leave it under your bed, you know it’s there and that it will stay there until you move it.)
If you drop a pebble in a pond, waves ripple away in circles. Particles sometimes travel like those waves. But they also can travel like a pebble. severija/iStockphoto
“The bottom line is, the quantum world just doesn’t work in the way the world around us works,” says David Lindley. “We don’t really have the concepts to deal with it,” he says. Trained as a physicist, Lindley now writes books about science (including quantum science) from his home in Virginia.
Here’s a taste of that weirdness: If you hit a baseball over a pond, it sails through the air to land on the other shore. If you drop a baseball in a pond, waves ripple away in growing circles. Those waves eventually reach the other side. In both cases, something travels from one place to another. But the baseball and the waves move differently. A baseball doesn’t ripple or form peaks and valleys as it travels from one place to the next. Waves do.
But in experiments, particles in the subatomic world sometimes travel like waves. And they sometimes travel like particles. Why the tiniest laws of nature work that way isn’t clear — to anyone.
Consider photons. These are the particles that make up light and radiation. They’re tiny packets of energy. Centuries ago, scientists believed light traveled as a stream of particles, like a flow of tiny bright balls. Then, 200 years ago, experiments demonstrated that light could travel as waves. A hundred years after that, newer experiments showed light could sometimes act like waves, and sometimes act like particles, called photons. Those findings caused a lot of confusion. And arguments. And headaches.
Wave or particle? Neither or both? Some scientists even offered a compromise, using the word “wavicle.” How scientists answer the question will depend on how they try to measure photons. It’s possible to set up experiments where photons behave like particles, and others where they behave like waves. But it’s impossible to measure them as waves and particles at the same time.
At the quantum scale, things can appear as particles or waves — and exist in more than one place at once. agsandrew/iStockphoto
This is one of the bizarre ideas that pops out of quantum theory. Photons don’t change. So how scientists study them shouldn’t matter. They shouldn’t only see a particle when they look for particles, and only see waves when they look for waves.
“Do you really believe the moon exists only when you look at it?” Albert Einstein famously asked. (Einstein, born in Germany, played an important role in developing quantum theory.)
This problem, it turns out, is not limited to photons. It extends to electrons and protons and other particles as small or smaller than atoms. Every elementary particle has properties of both a wave and a particle. That idea is called wave-particle duality. It’s one of the biggest mysteries in the study of the smallest parts of the universe. That’s the field known as quantum physics.
Quantum physics will play an important role in future technologies — in computers, for example. Ordinary computers run calculations using trillions of switches built into microchips. Those switches are either “on” or “off.” A quantum computer, however, uses atoms or subatomic particles for its calculations. Because such a particle can be more than one thing at the same time — at least until it’s measured — it may be “on” or “off” or somewhere in-between. That means quantum computers can run many calculations at the same time. They have the potential to be thousands of times faster than today’s fastest machines.
IBM and Google, two major technology companies, are already developing superfast quantum computers. IBM even allows people outside the company to run experiments on its quantum computer.
Experiments based on quantum knowledge have produced astonishing results. For example, in 2001, physicists at Harvard University, in Cambridge, Mass., showed how to stop light in its tracks. And since the mid-1990s, physicists have found bizarre new states of matter that were predicted by quantum theory. One of those — called a Bose-Einstein condensate — forms only near absolute zero. (That’s equivalent to –273.15° Celsius, or –459.67° Fahrenheit.) In this state, atoms lose their individuality. Suddenly, the group acts as one big mega-atom.
Quantum physics isn’t just a cool and quirky discovery, though. It’s a body of knowledge that will change in unexpected ways how we see our universe — and interact with it.
A quantum recipe
Quantum theory describes the behavior of things — particles or energy — on the smallest scale. In addition to wavicles, it predicts that a particle may be found in many places at the same time. Or it may tunnel through walls. (Imagine if you could do that!) If you measure a photon’s location, you might find it in one place — and you might find it somewhere else. You can never know for certain where it is.
Also weird: Thanks to quantum theory, scientists have shown how pairs of particles can be linked — even if they’re on different sides of the room or opposite sides of the universe. Particles connected in this way are said to be entangled. So far, scientists have been able to entangle photons that were 1,200 kilometers (750 miles) apart. Now they want to stretch the proven entanglement limit even farther.
Quantum theory thrills scientists — even as it frustrates them.
It thrills them because it works. Experiments verify the accuracy of quantum predictions. It also has been important to technology for more than a century. Engineers used their discoveries about photon behavior to build lasers. And knowledge about the quantum behavior of electrons led to the invention of transistors. That made possible modern devices such as laptops and smartphones.
But when engineers build these devices, they do so following rules that they don’t fully understand. Quantum theory is like a recipe. If you have the ingredients and follow the steps, you end up with a meal. But using quantum theory to build technology is like following a recipe without knowing how food changes as it cooks. Sure, you can put together a good meal. But you couldn’t explain exactly what happened to all of the ingredients to make that food taste so great.
Scientists use these ideas “without any idea of why they should be there,” notes physicist Alessandro Fedrizzi. He designs experiments to test quantum theory at Heriot-Watt University in Edinburgh, Scotland. He hopes those experiments will help physicists understand why particles act so strangely on the smallest scales.
Is the cat okay?
If quantum theory sounds strange to you, don’t worry. You’re in good company. Even famous physicists scratch their heads over it.
Remember Einstein, the German genius? He helped describe quantum theory. And he often said he didn’t like it. He argued about it with other scientists for decades.
“If you can think about quantum theory without getting dizzy, you don’t get it,” Danish physicist Niels Bohr once wrote. Bohr was another pioneer in the field. He had famous arguments with Einstein about how to understand quantum theory. Bohr was one of the first people to describe the weird things that pop out of quantum theory.
“I think I can safely say that nobody understands quantum [theory],” noted American physicist Richard Feynman once said. And yet his work in the 1960s helped show that quantum behaviors aren’t science fiction. They really happen. Experiments can demonstrate this.
Quantum theory is a theory, which in this case means it represents scientists’ best idea about how the subatomic world works. It’s not a hunch, or a guess. In fact, it’s based on good evidence. Scientists have been studying and using quantum theory for a century. To help describe it, they sometimes use thought experiments. (Such research is known as theoretical.)
In 1935, Austrian physicist Erwin Schrödinger described such a thought experiment about a cat. First, he imagined a sealed box with a cat inside. He imagined the box also contained a device that could release a poison gas. If released, that gas would kill the cat. And the probability the device released the gas was 50 percent. (That’s the same as the chance that a flipped coin would turn up heads.)
This is a diagram of the Schrödinger’s cat thought experiment. The only way to know if the poison was released and the cat is dead or alive is to open the box and look inside. Dhatfield/Wikimedia Commons (CC-BY-SA 3.0)
To check the status of the cat, you open the box.
The cat is either alive or dead. But if cats behaved like quantum particles, the story would be stranger. A photon, for instance, can be a particle and a wave. Likewise, Schrödinger’s cat can be alive and dead at the same time in this thought experiment. Physicists call this “superposition.” Here, the cat won’t be one or the other, dead or alive, until someone opens the box and takes a look. The fate of the cat, then, will depend on the act of doing the experiment.
Schrödinger used that thought experiment to illustrate a huge problem. Why should the way that the quantum world behaves depend on whether someone is watching?
Welcome to the multiverse
Anthony Leggett has been thinking about this problem for 50 years. He’s a physicist at the University of Illinois at Urbana-Champaign. In 2003, he won a Nobel Prize in physics, the most prestigious award in his field. Leggett has helped develop ways to test quantum theory. He wants to know why the smallest world doesn’t match with the ordinary one we see. He likes to call his work “building Schrödinger’s cat in the laboratory.”
Leggett sees two ways to explain the problem of the cat. One way is to assume that quantum theory will eventually fail in some experiments. “Something will happen that is not described in the standard textbooks,” he says. (He has no idea what that something might be.)
The other possibility, he says, is more interesting. As scientists conduct quantum experiments on larger groups of particles, the theory will hold. And those experiments will unveil new aspects of quantum theory. Scientists will learn how their equations describe reality and be able to fill in the missing pieces. Eventually, they will be able to see more of the whole picture.
Today, you decided to wear a certain pair of shoes. If there were multiple universes, there would be another world where you made a different choice. Today, there is no way to test this “many-world” or “multiverse” interpretation of quantum physics, however. fotojog/iStockphoto
Simply put, Leggett hopes: “Things that right now seem fantastic will be possible.”
Some physicists have proposed even wilder solutions to the “cat” problem. For example: Maybe our world is one of many. It’s possible that infinitely many worlds exist. If true, then in the thought experiment, Schrödinger’s cat would be alive in half the worlds — and dead in the rest.
Quantum theory describes particles like that cat. They may be one thing or another at the same time. And it gets weirder: Quantum theory also predicts that particles may be found in more than one place at a time. If the many-world idea is true, then a particle might be in one place in this world, and somewhere else in other worlds.
This morning, you probably chose which shirt to wear and what to eat for breakfast. But according to the many worlds idea, there is another world where you made different choices.
This weird idea is called the “many-world” interpretation of quantum mechanics. It is exciting to think about, but physicists have not found a way to test whether it’s true.
Tangled up in particles
Quantum theory includes other fantastic ideas. Like that entanglement. Particles may be entangled — or connected — even if they’re separated by the width of the universe.
Imagine, for instance, that you and a friend had two coins with a seemingly magical connection. If one showed up heads, the other would always be tails. You each take your coins home and then flip them at the same time. If yours comes up heads, then at the exact same moment you know your friend’s coin has just come up tails.
Entangled particles work like those coins. In the lab, a physicist can entangle two photons, then send one of the pair to a lab in a different city. If she measures something about the photon in her lab — such as how fast it moves — then she immediately knows the same information about the other photon. The two particles behave as though they send signals instantaneously. And this will hold even if those particles are now separated by hundreds of kilometers.
Story continues below video.
Quantum entanglement is really weird. Particles maintain a mysterious link that persists even if they are separated by light-years. VIDEO BY B. BELLO; IMAGE BY NASA; MUSIC BY CHRIS ZABRISKIE (CC BY 4.0); PRODUCTION & NARRATION: H. THOMPSONAs in other parts of quantum theory, that idea causes a big problem. If entangled things send signals to each other instantly, then the message might seem to travel faster than the speed of light — which, of course, is the speed limit of the universe! So that cannot happen.
In June, scientists in China reported a new record for entanglement. They used a satellite to entangle six million pairs of photons. The satellite beamed the photons to the ground, sending one of each pair to one of two labs. The labs sat 1,200 kilometers (750 miles) apart. And each pair of particles remained entangled, the researchers showed. When they measured one of a pair, the other one was affected immediately. They published those findings in Science.
Scientists and engineers are now working on ways to use entanglement to link particles over ever-longer distances. But the rules of physics still prevent them from sending signals faster than the speed of light.
Why bother?
If you ask a physicist what a subatomic particle really, truly is, “I don’t know that anyone can give you an answer,” says Lindley.
Many physicists are content with not knowing. They work with quantum theory, even though they don’t understand it. They follow the recipe, never quite knowing why it works. They may decide that if it works, why bother going any further?
Others, like Fedrizzi and Leggett, want to know why particles are so weird. “It’s far more important to me to find out what’s behind all of this,” Fedrizzi says.
Forty years ago, scientists were skeptical that they could do such experiments, notes Leggett. Many thought that asking questions about the meaning of quantum theory was a waste of time. They even had a refrain: “Shut up and calculate!”
Leggett compares that past situation to exploring sewers. Going into sewer tunnels might be interesting but not worth visiting more than once.
“If you were to spend all your time rummaging around in the bowels of the Earth, people would think you were rather strange,” he says. “If you spend all your time on the foundations of quantum [theory], people will think you’re a little odd.”
Now, he says, “the pendulum has swung the other way.” Studying quantum theory has become respectable again. Indeed, for many it has become a lifelong quest to understand the secrets of the tiniest world.
“Once the subject hooks you, it won’t let you go,” says Lindley. He, by the way, is hooked.
Power Words
atom The basic unit of a chemical element. Atoms are made up of a dense nucleus that contains positively charged protons and uncharged neutrons. The nucleus is orbited by a cloud of negatively charged electrons.
behavior The way something, often a person or other organism, acts towards others, or conducts itself.
electron A negatively charged particle, usually found orbiting the outer regions of an atom; also, the carrier of electricity within solids.
engineer A person who uses science to solve problems. As a verb, to engineer means to design a device, material or process that will solve some problem or unmet need.
entanglement (in quantum physics) A concept in quantum physics that holds that subatomic particles can be linked even if they are not physically near one another. Quantum entanglement can link the properties of things at great distances — perhaps at opposite ends of the universe.
equation In mathematics, the statement that two quantities are equal. In geometry, equations are often used to determine the shape of a curve or surface.
field An area of study, as in: Her field of research was biology. Also a term to describe a real-world environment in which some research is conducted, such as at sea, in a forest, on a mountaintop or on a city street. It is the opposite of an artificial setting, such as a research laboratory.
laser A device that generates an intense beam of coherent light of a single color. Lasers are used in drilling and cutting, alignment and guidance, in data storage and in surgery.
matter Something that occupies space and has mass. Anything on Earth with matter will have a property described as «weight.»
microchip A tiny wafer of semiconducting material (the chip), often silicon, which holds tiny electronic parts and the «wiring» needed to connect them to an electric circuit. Or a small computer chip that is implanted in goods or animals and acts like a tag. It holds information that can be retrieved as needed (such as an animal’s name or the inventory lot for commercial products.
multiverse A term to connote the idea that our universe may be one of many (perhaps an infinite number of alternative universes) and that different things may happen in each.
Nobel prize A prestigious award named after Alfred Nobel. Best known as the inventor of dynamite, Nobel was a wealthy man when he died on December 10, 1896. In his will, Nobel left much of his fortune to create prizes to those who have done their best for humanity in the fields of physics, chemistry, physiology or medicine, literature and peace. Winners receive a medal and large cash award.
particle A minute amount of something.
photon A particle representing the smallest possible amount of light or other electromagnetic radiation.
physics The scientific study of the nature and properties of matter and energy. A scientist who works in such areas is known as a physicist.
probability A mathematical calculation or assessment (essentially the chance) of how likely something is to occur.
proton A subatomic particle that is one of the basic building blocks of the atoms that make up matter. Protons belong to the family of particles known as hadrons.
quantum (pl. quanta) A term that refers to the smallest amount of anything, especially of energy or subatomic mass.
quantum mechanics A branch of physics dealing with the behavior of matter on the scale of atoms or subatomic particles.
quantum physics A branch of physics that uses quantum theory to explain or predict how a physical system will operate on the scale of atoms or sub-atomic particles.
quantum theory A way to describe the operation of matter and energy at the level of atoms. It is based on an interpretation that at this scale, energy and matter can be thought to behave as both particles and waves. The idea is that on this very tiny scale, matter and energy are made up of what scientists refer to as quanta — miniscule amounts of electromagnetic energy.
radiation (in physics) One of the three major ways that energy is transferred. (The other two are conduction and convection.) In radiation, electromagnetic waves carry energy from one place to another. Unlike conduction and convection, which need material to help transfer the energy, radiation can transfer energy across empty space.
satellite A moon orbiting a planet or a vehicle or other manufactured object that orbits some celestial body in space.
science fiction A field of literary or filmed stories that take place against a backdrop of fantasy, usually based on speculations about how science and engineering will direct developments in the distant future. The plots in many of these stories focus on space travel, exaggerated changes attributed to evolution or life in (or on) alien worlds.
sewer A system of water pipes, usually running underground, to move sewage (primarily urine and feces) and stormwater for collection — and often treatment — elsewhere.
skeptical Not easily convinced; having doubts or reservations.
smartphone A cell (or mobile) phone that can perform a host of functions, including search for information on the internet.
subatomic Anything smaller than an atom, which is the smallest bit of matter that has all the properties of whatever chemical element it is (like hydrogen, iron or calcium).
superposition (in quantum physics) The ability of some minute subatomic-scale particle to be more than one place at the same time. It has to do with particles in the quantum world having the weird capacity to exist in all possible states (or positions) at once. (in geology) An understanding that unless subsurface strata of soil and rock have been disturbed somehow, the age of the materials will get successively older with depth.
theory (in science) A description of some aspect of the natural world based on extensive observations, tests and reason. A theory can also be a way of organizing a broad body of knowledge that applies in a broad range of circumstances to explain what will happen. Unlike the common definition of theory, a theory in science is not just a hunch. Ideas or conclusions that are based on a theory — and not yet on firm data or observations — are referred to as theoretical. Scientists who use mathematics and/or existing data to project what might happen in new situations are known as theorists.
thought experiments Mathematical analyses of ideas, situations or events. They are not based on real-world tests in a lab or the environment. They instead use numbers and relationships between mathematical operations to test whether something can or will happen. This is also known as theoretical research.
transistor A device that can act like a switch for electrical signals.
universe The entire cosmos: All things that exist throughout space and time. It has been expanding since its formation during an event known as the Big Bang, some 13.8 billion years ago (give or take a few hundred million years).
verify (n. verification) To demonstrate or confirm in some way that a particular claim or suspicion is true.
wave A disturbance or variation that travels through space and matter in a regular, oscillating fashion.
wave-particle duality The concept that a subatomic particle can exhibit properties of a wave and a particle. But at any one time it will only show attributes of being either a wave or a particle.
wavicle A term invented in 1928 by the British physicist Arthur Stanley Eddington to convey the duality of light and radiation as being both waves and particles, although they never appear to be both at the same time.
Citations
Journal: J. Yin et al. Satellite-based entanglement distribution over 1200 kilometers. Science. Vol. 356, June 16, 2017, p. 1140. doi: 10.1126/science.aan3211.
Journal: M. Ringbauer et al. Measurements on the reality of the wavefunction. Nature Physics. Vol. 11, March 2015, p. 249. doi: 10.1038/NPHYS3233.
Вопрос
A. Goodness knows how many inky embarrassments may lurk in these pages yet, but it is thanks to Dr Wiseman and all of those whom I am about to mention that there aren’t many hundreds more. I cannot begin to thank adequately those who helped me in the preparation of this book. I am especially indebted to the following, who were uniformly generous and kindly and showed the most heroic reserves of patience in answering one simple, endlessly repeated question: ‘I’m sorry, but can you explain that again?
B. It may be that our universe is merely part of many larger universes, some in different dimensions, and the Big Bangs are going on all the time all over the place. Or it may be that space and time had some other forms altogether before the Big Bang — forms too alien for us to imagine — and that the Big Bang represents some sort of transition phase, where the universe went from a form we can’t understand to one we almost can.
C. This is a very popular Japanese form of poetry. It is brief, related to the season/nature, expresses a sense of awe or insight, written using concrete sense images and not abstractions, in the present tense. It is often written as three lines, of seventeen syllables arranged in a sequence 5, 7, 5, though not necessarily. A verbal snapshot, capturing the essence of a moment/scene. Some haiku are only a line or two. The idea is to capture a moment.
D. In April 1737, at age 52, Handel apparently suffered a stroke which disabled the use of four fingers on his right hand, preventing him from performing. In summer the disorder seemed at times to affect his understanding. Nobody expected that Handel would ever be able to perform again. But whether the affliction was rheumatism, a stroke or a nervous breakdown, he recovered remarkably quickly. To aid his recovery, Handel had travelled to Aachen, a spa in Germany. During six weeks he took long hot baths, and ended up playing the organ for a surprised audience.
E. When you sit down to dinner in a town house, your expectations will probably be governed by what you see around you. If you are in a small wooden building, dining in a small, poorly lit hall and being attended by your host’s wife, then your fare will probably be less tasty than a yeoman’s meal. If your host is an important merchant, on the other hand, and you are being entertained in the welllit hall of a large house, then you can expect food far richer and more varied than the peasant could dream of offering.
F. Anyone who is an American citizen, at least 18 years of age, and is registered to vote may vote. Each state has the right to determine registration procedures. A number of civic groups, such as the League of Women Voters, are actively trying to get more people involved in the electoral process and have drives to register as many people as possible. Voter registration and voting among minorities has dramatically increased during the last thirty years, especially as a result of the Civil Rights Movement.
G. The Games have grown in scale to the point that nearly every nation is represented. Such growth has created numerous challenges, including boycotts, doping, bribery of officials, and terrorism. Every two years, the Olympics and its media exposure provide unknown athletes with the chance to attain national, and in particular cases, international fame. The Games also constitute a major opportunity for the host city and country to showcase itself to the world.
Can you imagine that our universe was smaller than an atom
Прочитайте текст. Заполните пропуски в предложениях под номерами В04-В12 соответствующими формами слов, напечатанных заглавными буквами справа от каждого предложения. TEST 08 (part 1)
B4
50 years ago people even …………………… of computers, and today we cannot imagine life without them. Computer technology is the fastest-growing industry in the world.
NOT HEAR
B5
The first computer …………………… the size of a minibus and weighed a ton.
BE
B6
Today, its job can …………………… by a chip the size of a pin head. And the revolution is still going on.
DO
B7
The next generation of computers …………………… to talk and even think for themselves. Of course, they’ll be a lot simpler than human brains, but it will be a great step forward. Such computers will help to diagnose illnesses, find minerals, identify criminals and control space travel.
BE ABLE
B8
Some people say that computers are dangerous, but I …………………… with them. They save a lot of time. They seldom make mistakes.
NOT AGREE
B9
It’s much …………………… to surf the Internet than to go to the library.
EASY
B10
On-line shopping …………………… it possible to find exactly what you want, saving both time and money.
MAKE
B11
E-mail …………………… a great invention, too. It’s faster than sending a letter and cheaper than sending a telegram.
BE
B12
All in all, I strongly believe that computers are a useful tool. They …………………… our life for the better. So why shouldn’t we make them work to our advantage?
CHANGE
Английский язык для студентов-физиков (стр. 5 )
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This scenario should not surprise us. If the most important constituents of the present Universe are destined to disappear, they will surely be replaced by something new. From what we know of the past evolution of the Universe this has happened several times in the past as the Universe went from one dominated by many distinct particle species to one dominated by photons to one dominated by protons.
Some physicists have tried to describe the Universe that would develop after the protons have decayed or the black holes have swallowed up matter as we know it. These considerations would apply either to the large finite Universe of the present scenario (so long as it is still expanding) or to the next scenario, in which the Universe is finite and expands forever. The analysis is not complete, but it suggests that some forms of matter other than photons would persist (continue to act) in such a future Universe.
The protons that are present in our Universe would decay into positrons. These positrons can annihilate with the electrons already present to yield photons. *However, the extent to which this happens depends on the rate of expansion of the Universe, which by increasing the average distance between particles, decreases the chance of annihilation. The analyses that have been given suggest that many of the positrons will Find themselves too faraway from an electron to annihilate. Consequently, some positrons, and an equal number of electrons, will remain indefinitely. The same appears to be true for neutrinos of finite mass, if there are any such particles. In any event, these particles that remain could form more complex stable structures, bound together by gravity orelectromagnetism. These structures will be immensely largerthanthe familiar atoms, indeed, some maybe larger than the present observable Universe!
How complex these structures can become is an unsolved problem. It is difficult to analyse it in detail, because of the extreme disparity in scale between the structures that are familiar to us and anything that may evolve in the late
Universe. However, this change in scale is not unprecedented in the history of the Universe. *In its earliest moments, the whole region that eventually evolved into the present Universe was much smaller than an atom or even a subatomic particle. *If there could have been an intelligence that functioned in the early instants of the Universe, the familiar structures of our present Universe would seem as grossly extended as the supergalactic atoms of the late Universe would appear to us. *It is not beyond our ability to understand complexity in the late Universe, once we set our minds to it. 1 believe that understanding that complexity, and solving its related problems, will represent a novel branch of science in the future.
*No matter how large, ifthe Universe is finite, eventually the expansion will cease and contraction will take over. The details of what will happen during this contraction would be rather different from those in Scenario 1, because the contents of the Universe would be different in each case. *Yet, the outcome is no less mysterious, so poorly are the phases of turnover and contraction understood. *If we learn that the Universe is finite, unraveling what will take place during these phases will become one of the important endeavours of future science.
• Try to guess the meaning of the words given in italics in the text.
• Translate the sentences marked with an asterisk.
• Look through the text and try to answer the following questions.
1. What conditions are needed for the Universe to be larger than that in Scenario 1?
2. What will the future of the Universe depend upon according to Scenario 2?
4. What do scientists hypothesize concerning the present forms of matter?
(to be done in writing)
1. Translate into Russian.
1. In one specific cosmological model, recently proposed by an American physicist Alan Guth, known as the inflationary universe, all of the visible universe and a great deal of space-time beyond it, originated in a tiny bubble in the very early universe.
2. This bubble contained a high level of quantum fields which caused it to undergo an expansion much more rapid than that expected according to
the standard Big Bang theory, where the expansion is influenced only by the presence of subatomic particles.
3. The rapid expansion diluted the material contents of our universe to a very low density, and none ofthe particles present in the universe before this «inflation» began are present today.
4. Instead, the matter in the present Universe was produced by a phase transition at the end ofthe inflation, in which some of the energy that was contained in background fields became converted to particles.
5. Inthc inflationary Universe, space-time beyond the volume of expansion ofthe original bubble would be different from space-time inside it.
6. In this model, the different regions of the Universe arc somewhat like different cultures, developing independently of one another, and unaware of each other’s existence.
7. We are presently unaware of conditions beyond our own bubble, because there has not yet been enough time since the beginning of the Universe for any light originating outside to reach us.
8. If the Universe continues to exist indefinitely, we would eventually become aware of these foreign regions of space-time — and find that matter and energy in these regions have very different properties from those familiar to us.
2. Translate into English.
1. Этот журнал содержит ряд статей на данную тему.
2. Если бы вам удалось достать его, мы могли бы получить много ценной информации.
3. Одна из статей даст интересную трактовку (treatment) данной темы.
4. В ней дается обзор (review) данной темы в целом.
5. Я думаю, что эта статья представляет собой ценный вклад в науку.
GRAMMAR: THE SUBJUNCTIVE MOOD
1.
It is essential desirable doubtful, etc.
The laws of mechanics require suggest
demand propose, etc.
that the distance of each body (should)be related to.
Законы механики требуют, чтобы расстояние каждого тела. находилось в соответствии с.
the Moon were one halfit would «]
might I be. could J
Если бы Луна составляла половину то она была бы.
If it were to + Infinitive = если бы (относится к будущему) If I were to do that, what would you say?
• Read the following extract. Pay attention to the grammar forms in bold type. Translate them into Russian.
1. Now it is essential that astronomers (should) determine the mass of large numbers of other objects in the Universe. There is the Moon, for instance,
Earth’s one satellite, which is 384,00 km from us (1 km is = 5/8 mi) and which circles the Earth once every 27 1/3 days.
More precisely both the Earth and the Moon circle a common center of gravity.
2. The laws of mechanics require that the distance of each body from that center of gravity (should) be related to its mass. In other words, if the Moon were one half as massive as the Earth, it would be two times as far from the center of gravity as the Earth is, if it were one third as massive as the Earth, it would be three times as far; and so on.
After Isaac Asimov. «The Collapsing Universe».
WORD AND PHRASE STUDY
Question п. — вопрос, проблема
v. — сомневаться, ставить под вопрос
in question — исследуемый, рассматриваемый
(syn. involved о ко юром идет речь, concerned, in issue, in point)
open to question — сомнительный, спорный
beyond question — вне сомнения
out ofthe question — не может быть и речи
Translate into Russian.
1. The method involved provided them with interesting results.
2. The quantity in question is related to the volume of this container.
3. Our being close to the solution ofthe problem is out of the question.
• Read the passage and answer these two questions:
1. What does the Universe look like according to the chaotic inflation hypothesis?
2. What cosmological problems does this hypothesis account for?
The division of the Universe into many mini-Universes also makes it possible to suggest an answer to the question of why our space is three-dimensional. The process of compactification (shrinking and rolling up of some of the original dimensions) may occur differently in domains that are far enough apart from one another. And, once again, life, as we know it, may only exist in those domains which are three-dimensional. The physicist Paul ‘ihrenfest pointed out, as long ago as 1917, that the threc-dimcnsienality of space is intimately connected with the way matter behaves.
Both gravitational and electromagnetic forces obey inverse square laws in our Universe and by generalizing the equations that describe these interactions and solving them in other dimensions mathematicians have shown that in space with n dimensions the result is always an n— 1 power law. In four dimensions, the laws would both be inverse cubes and, it turns out, there would be no stable orbits for cither planets in solar systems or electrons in atoms. The same is true for all higher dimensions. In a two-dimensional Universe, tilings are no better, because n— 1 is 1, and neither gravity nor elcctromagnetism is affected by distance at all. So atoms and planetary systems may only exist together in a domain with three dimensions of space, like our domain of the Universe. Sothc chaotic inflation scenario provides a simple solution to most of the problems with the standard big bang model.
The inflationary Universe scenario is now only five years old, and is still rapidly changing and developing as new ideas come to the fore. We do not know which part of the scenario will survive even for the next five years. But already it has proved able to solve about ten major cosmological problems in one simple model. Ideas which would have sounded like fantastic science-fiction only a decade ago, such as the creation of all the matter in the observable Universe (I0-» tons) by gravitational forces operating inside a domain which originally contained less than 10s g of matter and was less than 10″» cm across, now seem to be necessary ingredients in any complete theory of the Universe.
And how long did all that activity take? 1 have saved the most startling fact until last. The phase of exponential inflation that is critical to our modern understanding of the Universe probably lasted for less than 10’30 seconds.
• Look through the passage and find English equivalents for the following Russian phrases.
достаточно далеко отстоять друг от друга; подчиняться закону обратных квадратов; степенной закон; то же справедливо и для; ситуация не лучше и для; по мере выдвижения новых идей; дает простое решение; являются, по-видимому, необходимыми составляющими; поразительный факт; принимают различные значения; для решающего (переломного) понимания
• Match each word in A with its synonym in B.
A. 1. to survive; 2. ingredient; 3. to startle; 4. to shrink; 5. true
B. a) component; b) to astonish; c) to remain alive; d) to contract;
e)exact
• Match each word in A with its antonym in B.
A. 1. to stop; 2. to shrink; 3. far apart from; 4. slow; 5. true; 6. inverse;
7. to survive
B. a) direct; b) to expand; c) rapid; d) next to; c) false; 0 to die; g) to
last
• Answer the following questions using the information from the text or any other sources.
1. What is the Universe according to the chaotic inflation scenario?
2. What problems does the chaotic hypothesis remove and why?
3. What does each domain of the Universe look like?
4. How does this hypothesis explain the dimensionality of our system?
5. How does the author account for the first instants of the origin of the Universe?
6. What really fantastic science-fiction figures do scientists have to realize in developing a complete theory of the Universe?
7. Which of the facts impress your imagination most?
Before reading the passage below, let us remember Scenarios 1 and 2 of a finite small and large Universes.
Enough matter for the Universe to close on itself.
The density of energy in the Universe is slightly larger than needed for the Universe to close.
1. Middle-aged Universe.
2. Expansion —> stop —» contraction —> Big Crunch.
3. Protons will not have time to decay.
1. The Universe is in its infancy.
2. Very long expansion —> stop —> contraction —> Big Crunch.
3. Decay of protons into lighter particles, spontaneous collapse of matter into black holes. Annihilations of neutrinos and anti-neutrinos. I nstability of galaxies.
• Now, read the passage and give your opinion on the fate of the Universe according to Scenario 3.
SCENARIO3. AN INFINITE UNIVERSE
*If the density of matter were less than a critical amount, corresponding to aboutgrams per cubic centimeter — about ten milligrams in a region the size of the Earth — then the Universe is infinite, and will expand for ever. «■Objects in the Universe will, on the average, get farther and farther apart, except for those such as the contents ofthe solar system, which are held together by forces such as gravity. As in Scenario 2, the contents of the Universe will change, and their eventualform will depend on presently unknown properties of subatomic particles and on the end state of black holes. On the whole, the future ofthe Universe in Scenario 3 is about the same as in Scenario 2, except that the expansion never slows to zero and reverses. The Universe of Scenario 3 becomes one in which protons, electrons, neutrinos and their antiparticles are spread ever more thinly through larger and larger regions of space. *Once again, however, we do not know whether gravity and elcctromagnetism would allow these objects to form complex structures able to persist indefinitely.
However, there is a missing piece in our puzzle, one that might apply to the large finite Universe. Most cosmological models have assumed that the Universe is homogeneous — that all parts of it are the same, including those beyond the reach of our telescopes and hence unknown. The assumption of homogeneity has been made in order to simplify the mathematical description that physicists give to the Universe.
*Recently, this assumption has been questioned. We have seen that physicists believe that some features of the present Universe depend on the broken symmetry that occurred in the early Universe. Yet this symmetry breaking need not have occurred uniformly over the whole of spacetime. Just as a lake in winter can be liquid in some regions and solid in others, so might different regions of space be in different phases, which would imply different physical properties for the matter in it. For example, the surplus of what we call matter in our visible Universe might be replaced by equal amounts of matter and ant imatter or a surplus of antimatter in parts of space-time beyond our present horizon. But now let us return to the view that the properties of particles will change slowly as the Universe expands. Some scientists have predicted that rapid phase transitions similar to those that took place in the early Universe will occur in the future. This could happen if the present configuration of quantum fields in our region of space has more energy than another configuration, and is therefore unstable against transformation into the lower energy configuration.
*lf such phase transitions occur, they are expected to begin in one place, perhaps as the result of a random fluctuation, and then spread outward at the speed of light, eventually encompassing every point in space. *As the transition passes through any point, those properties of matter that depend on the background quantum fields present there, would have to change suddenly because of the new conditions. *A sudden change in the properties of subatomic particles would lead to tremendous changes in any structures composed of Ihcm, and it is unlikely that these structures would persist. It has even been suggested that such a phase change has begun in anothersection ofthe Universe, and is now approaching us at the speed of light. But there is no evidence forthis possibility, and we need to analyse it further before adding it to the list of environmental catastrophes that we need to worry about.
If the Universe continues to expand long enough for the matter to change its form drastically, then intelligent creatures may have agreater role to play in the distant future than they would in a Universe that eventually contracts. They would have to grapple with two problems: the disappearance of the protons and bound neutrons that form the material bases for most structures in the present Universe, and the ever smaller amounts of free energy that would be available to preserve order in whatever structures might replace them. *No good solutions to these problems have yet emerged, but since we have been studying them for only a few years, and will not need the answers for 10J0yearsorso, wc need not despair.
• Try to guess the meaning of the words given in italics in the text.
• Translate the sentences marked with an asterisk.
• Look through the text and try to answer the following questions.
1. What conditions arc needed for our Universe to be infinite?
2. What factors will play the key role in the fate of an infinite Universe?
3. What fatal consequences could the inhomogencity of the Universe lead to?
4. Are there any reasonable solutions to the problems?
5. Why does the author think that human beings need not despair about the future of the Universe?
(to be done in writing)
1. Translate into Russian.
1. To a physicist a liquid is very symmetric — whichever way you look at it, it looks the same.
2. But when the liquid cools and begins to crystallize, different regions of the liquid may begin to crystallize with different orientations of their growing crystal lattices.
3. When these different crystal lattices meet one another they join together as best as they can and inevitably produce boundaries called defects.
4. Within each domain there is a preferred orientation ofthe crystal lattice, but adjacent domains separated by a defect may have very different orientations.
5. The overall symmetry has been destroyed.
6. During the phase transitions ofthe cooling early Universe, something similar to the crystallization of a liquid may have happened.
7. As the Universe continued to expand and cool, the quantum fields went through several distinct phase transitions.
8. Each of these led to a change in the overall level of quantum fields everywhere in space and an associated change in the properties of some subatomic particles.
9. The last of the phase changes is thought to have taken place when the temperature ofthe Universe was about 1011 times as great as today.
10. After that, all subatomic particles had the same properties that we find them to have now.
11. According to theoretical analyses, all of these extraordinary changes took place within a very short period of time — perhaps in the very microsecond or so after the expansion ofthe Universe began.
12. In other words, the main subatomic features of our Universe were determined in a flash of time, and the consequences have been working themselves out ever since.
2. Translate into English. Use such phrases as in question (progress), under consideration (discussion, study).
1. Открытие, о котором идет речь, пока широко не известно.
2. Исследуемая проблема может повлиять на развитие всей отрасли.
3. Обсуждаемые сейчас данные тесно связаны с этой проблемой.
4. Рассматриваемый подход кажется вполне удовлетворительным.
5. Исследовательская работа, проводимая в нашей лаборатории, даст хорошие результаты.
THE WORLD OF SUBATOMIC PARTICLES
UNIT NINE GRAMMAR’. THE SUBJUNCTIVE MOOD
1 как если бы, как будто бы
The object behaves as if it were Тело ведет себя так, как будто бы
given some energy at the start. ему сообщили.
2. that
so that
in order that
lest чтобы не
Keep the temperature so that the Поддерживайте необходимую substance (should) not be cooled. температуру, чтобы вещество не
3. though J хотякакбыни
although J
Though he may (might) be busy he Как бы он ни был занят, он за-will complete the work on time. кончит работу вовремя.
Sentences to be translated.
1. Acid is added so that the metal should dissolve.
2. This gas must be kept in a special vessel lest it be evaporated.
3. Though such an apparatus be developed, this would not solve the problem.
4. One cannot speak of particles and waves as though they were two different things.
5. Make exact calculations lest you should fail with your experiment.
6. Be careful lest you should make mistakes in calculations.
7. In determining the orbit of a planet we may neglect accelerations ofthe sun and treat it as if it were at rest.
WORD AND PHRASE STUDY
• Form adverbs from the following adjectives and translate them *****ssian.
pure, comparative, rapid, equal, ordinary, certain, accidental, radioactive, previous, rare, heavy, presumble
• Read the passage attentively and be prepared to describe the phenomenon of natural radioactivity.
THE DISCOVERY OF RADIOACTIVITY
As is the case with so many other discoveries, the discovery ofthe phenomenon of radioactivity was purely accidental. It was discovered in 1896 by a French physicist, A. H. Becquerel (1852—1908), who was interested at that time in the phenomenon of fluorescence, i. e. the ability of certain substances to transform the ultraviolet radiation that falls on them into visible light. In one of the drawers of his desk Becquerel kept a collection of various minerals that he was going to use for his studies, but because of other pressing matters, the collection remained untouched fora considerable period of time. It happened that in the drawerthere were also several unopened boxes of photographic plates, and one day Becquerel took one of the boxes in order to photograph something or other. When he developed the plates he was disappointed to find that they were badly fogged, as if previously exposed to light. A check on other boxes showed that they were in the same poor condition, which was difficult to understand since all the boxes were sealed and the plates inside were wrapped in thick black paper. What could be the cause of this mishap? Could it have something to do with one ofthe minerals in the drawer? Being of an inquisitive mind, Becquerel investigated the situation and was able to trace the guilt to a piece of uranium ore labeled «Pitchblende from Bohemia». The reader must take into account, of course, that at that time the name «uranium» was not in vogue as it is today, and that, in fact, only very few people, even among scientists, had ever heard about that comparatively rare and not very useful chemical element. But the ability of a uranium compound to fog photographic plates through a thick cardboard box and a layer of black paper rapidly brought this obscure clement to a prominent position in physics.
The existence of penetrating radiation that could pass through layers of ordinarily opaque materials as if they were made of clear glass was a recognized fact at the time of Becquerel’s discovery. In fact, only a year earlier (1895) a German physicist, Wilhclm Roentgen (1845—1923), discovered what arc now known as X-rays, which can penetrate equally well through cardboard, black paper, or the human body.
Although special high voltage equipment is required to produce X-rays, the radiation «discovered by Becqucrel was flowing quite steadily and without any external excitation from the piece of uranium ore resting in his desk. What could be the origin of this unusual radiation? Why was it specifically associated with the clement uranium and, as studies found, with two other heavy elements known as thorium and actinium? The early studies of the newly discovered phenomenon, which was called «radioactivity», showed that the emission of mysterious radiation was completely unaffected by physical or chemical conditions. We can stick a radioactive element into a very hot flame or drop it into liquid air without the slightest effect on the intensity ofthe mysterious radiation it emits. No matter whether we have pure metallic uranium, or its oxide which is contained in pitchblende, the radiation flows out at a rate proportional to the amount of uranium in the sample. These facts ruled out any possibility of ascribing the phenomenon of radioactivity to any kind of chemical properties of this element, and led the early investigators to the conclusion that the phenomenon of radioactivity is the intrinsic property of the atoms of these peculiar elements and that its cause must be deeply rooted in the atomic interior.
• Find equivalents for the following Russian phrases.
как это происходит со многими другими открытиями; чисто случайное; интересоваться; видимый свет; из-за других неотложныхдел; в течение значительного периода времени; проявить пластины; были в таком же плохом состоянии; причина этой неудачи; могло ли это быть связано с; быть популярным; проникающая радиация; светонепроницаемые материалы; на излучение совершенно не влияет; без малейшего влияния; эти факты исключали возможность; причина, должно быть, кроется; внутреннее строение атома.
Re-read the passage and answer the following questions.
1. Who was the phenomenon of natural radioactivity discovered by?
2. Was this discovery really made quite accidentally?
3. What problem did Becquerel study at the time?
4. What did he keep minerals for in one ofthe drawers of his desk?
5. What did he see when he developed the photographic plates?
6. Why did he begin checking all the boxes with the plates?
7. Under what conditions were the boxes kept?
8. What was the cause of this mishap?
9. Was Becquerel greatly surprized to discover the radiation?
10. What penetrating radiation was discovered a year before that?
11. Who discovered this radiation?
12. Who were the first investigators ofthe phenomenon of radioactivity discovered by Becquerel?
13. What conclusion did the first investigators come to? Why did they come to such a conclusion?
14. What substances is the radiation emitted from?
Be prepared to say a few words about.
1. The history ofthe discovery of natural radioactivity.
2. Radioactive elements and types of radioactive emissions.
3. Radioactive processes in nature.
4. Radioactive emissions and their applications (radioisotopes, radiobiology, radiocarbon dating, radiodiagnosis).
Match each word in Column I with its synonym in Column II.
to be the case, because of, since, to take into account, no matter, to affect, to cause, to be in vogue, to rule out
to exclude, regardless of, to influence, because, to happen, to be in fashion, on account of, to take into consideration, to bring about
• Fill in the blanks with the proper word using the words in brackets.
(purified, purely, purification)
1. The process of. is rather complicated.
It is a. theoretical problem.
How is the material. in this case?
The discovery ofthe phenomenon of radioactivity was. accidental. (excited, excitation)
2. The radiation discovered by Becquerel was flowing without any external
. from the piece of uranium ore.
The highly. atoms arc often called Rydbergatoms, aftcrthe Swedish spectroscopist Yohanncs Rydberg.
Both the ion and target atom undergo electronic. during the collision. (exposed, exposure)
3. The technique is based on the use of long. to record an object’s motion.
The plates were badly fogged, as if previously. to light.
Several ofthe animals which were. to radiation have died since.
• Skim the passage rapidly (2 min.) and answer the following questions.
1. Did Becquerel observe in the experiment exactly what he expected to see?
2. What three rays did the original beam split into?
3. What were these rays called?
In order to study the nature of the discovered radiation, Becquerel arranged the following very simple experiment. He placed a small amount of uranium in a deep hole made in a lead block so that only a thin beam of radiation emerged from the groove. He also placed a magnet over the block in such a way that the magnetic lines of force were running perpendicular to the direction of the emerging beam. Under these conditions one could expect three different results.
If the radiation emitted by uranium were short electromagnetic waves similar to X-rays, no deflection should take place.
If, on the otherhand, the radiation were fast-moving electric particles, like the cathode and anode rays in J J. Thomson’s tube, the beam should be deflected to the left in the case of a negative charge and to the right in the ease of a positive one. In Becquerel’s experiment all three things happened, and the original beam emerging from the hole split into three parts. The part that consisted of particles carrying a positive charge was named ос-rays and was later proved (by Rutherford) to be a stream of doubly ionized helium atoms, i. e. a stream of helium nuclei. The part consisting of negatively charged particles, which turned out to be ordinary electrons, was named fj-rays, whereas the undeflected beam formed by short-wave electromagnetic radiation similar to X-rays received the name of y-rays.
• Re-read the passage and say a few words about the three kinds of radioactive rays. Give a headline to the text.
• Give a free translation of the following passage.
До открытия природной радиоактивности в конце XIX в. ядерные процессы оставались неизвестными.
Испускание излучения ураном, открытое в 1896 г. А. Беккерелем, было первым явлением ядерного происхождения, наблюдаемым человеком. В то время были только что открыты В. Рентгеном Х-лучи, создаваемые катодными лучами втрубках, в которых наблюдаласьтакже сильная флуоресценция. А. Пуанкаре выдвинул гипотезу, что испускание X-лучей может быть связано с явлением флуоресценции. А. Беккерель, желая проверить это предположение, использовал в качестве флуоресцирующих веществ соли урана, применявшиеся в работах его отцом. Он обнаружил, что соли действительно испускают излучение, способное производить фотографическое действие через л исток бумаги и ионизировать воздух подобно рентгеновским лучам, однако испускание этого излучения наблюдается также хорошо и с нефлуоресцирующими соединениями урана. Мари Кюри предприняла изучение этого нового явления в декабре 1897: она произвела ионизационным методом точное измерение интенсивности излучения урана и показала, что аналогичное излучение испускается торием.
(to be done in writing)
1. Translate into Russian.
1. It is necessary that the intensity of radiation should be measured very accurately.
2. The object behaves as if it were given some energy at the start.
3. Keep the temperature lest the substance should be overcooled.
4. In some calculations the air is treated as if it had no viscosity.
5. He suggested that the tunnel diode devices should be constructed from heavily doped semiconductors.
6. The whole weight of a body acts as though it were concentrated at a single point, this point being called the centre of gravity.
7. It is desirable that the errorsignal should be isolated from the detector.
8. The laws of mechanics require that the distance of each body from the center of gravity should be related to its mass.
2. Translate into English.
1. Предлагается, чтобы эксперименты провели в совершенно иных условиях.
2. Как бы мне хотелось принять участие в этой конференции!