Task 10. Make the written translation into Russian ( 2,200 characters).

To the ancients, the processes of image formation were full of mystery. Indeed, for a long time there was a great discussion as to whether, in vision, something moved from the object to the eye or whether something reached out from the eye to the object. By the beginning of the 17th century, however, it was known that rays of light travel in straight lines, and in 1604 Johannes Kepler, a German astronomer, published a book on optics in which he postulated that an extended object could be regarded as a multitude of separate points, each point emitting rays of light in all directions. Some of these rays would enter a lens, by which they would be bent around and made to converge to a point, the «image» of the object point whence the rays originated. The lens of the eye was not different from other lenses, and it formed an image of external objects on the retina, producing the sensation of vision. There are two main types of image to be considered: real and virtual. A real image is formed outside the system, where the emerging rays actually cross; such an image can be caught on a screen or piece of film and is the kind of image formed by a slide projector or in a camera. A virtual image, on the other hand, is formed inside an instrument at the point where diverging rays would cross if they were extended backward into the instrument. Such an image is formed in a microscope or telescope and can be seen by looking into the eyepiece.

Optics had progressed rapidly by the early years of the 19th century. Lenses of moderately good quality were being made for telescopes and microscopes, and in 1841 the great mathematician Carl Friedrich Gauss published his classical book on geometrical optics. In it he expounded the concept of the focal length and cardinal points of a lens system and developed formulas for calculating the position and size of the image formed by a lens of given focal length. Between 1852 and 1856 Gauss’s theory was extended to the calculation of the five principal aberrations of a lens, thus laying the foundation for the formal procedures of lens design that were used for the next 100 years. Since about 1960, however, lens design has been almost entirely computerized, and the old methods of designing lenses by hand on a desk calculator are rapidly disappearing.

By the end of the 19th century numerous other workers had entered the field of geometrical optics, notably an English physicist, Lord Rayleigh, and a German physicist, Ernst Karl Abbe. Since 1940 there has been a great resurgence in optics on the basis of information and communication theory, which is treated at length below.

Quantum Mechanics

Quantum mechanics (QM – also known as quantum physics, or quantum theory) is a branch of physics dealing with physical phenomena at microscopic scales, where the action is on the order of the Planck constant. Quantum mechanics departs from classical mechanics primarily at the quantum realm of atomic and subatomic length scales. QM provides a mathematical description of much of the dual particle-like and wave-like behaviour and interactions of energy and matter.

In advanced topics of quantum mechanics, some of these behaviours are macroscopic and only emerge at extreme (i.e. very low or very high) energies or temperatures. The name quantum mechanics derives from the observation that some physical quantities can change only in discrete amounts (Latin quanta), and not in a continuous way. For example, the angular momentum of an electron bound to an atom or molecule is quantized. In the context of quantum mechanics, the wave–particle duality of energy and matter and the uncertainty principle provide a unified view of the behavior of photons, electrons, and other atomic-scale objects.

The mathematical formulations of quantum mechanics are abstract. A mathematical function called the wave function provides information about the probability amplitude of position, momentum, and other physical properties of a particle.

The earliest versions of quantum mechanics were formulated in the first decade of the 20th century. At around the same time, the atomic theory and the corpuscular theory of light (as updated by Einstein) first came to be widely accepted as the scientific fact; these latter theories can be viewed as quantum theories of matter and electromagnetic radiation, respectively. The early quantum theory was significantly reformulated in the mid-1920s by Werner Heisenberg, Max Born, Wolfgang Pauli and their collaborators, and the Copenhagen interpretation of Niels Bohr became widely accepted. By 1930, quantum mechanics had been further unified and formalized by the work of Paul Dirac and John von Neumann, with a greater emphasis placed on measurement in quantum mechanics, the statistical nature of our knowledge of reality, and philosophical speculation about the role of the observer. Quantum mechanics has since branched out into almost every aspect of the 20th century physics and other disciplines, such as quantum chemistry, quantum electronics, quantum optics, and quantum information science. Much 19th century physics has been re-evaluated as the «classical limit» of quantum mechanics, and its more advanced developments in terms of the quantum field theory, the string theory, and speculative quantum gravity theories. (From www.bbc.co.uk )

Lasers

Lasers (Light Amplification by Stimulated Emission of Radiation) are _(1)_ which amplify light and produce beams of light which are very intense, directional, and pure in colour. Based on the laser medium used, lasers are generally classified as _(2)_ state, gas, semiconductor, or liquid.

When lasers were invented in 1960, some people thought they could be used as «death rays». In the 1980s, the United States experimented with lasers as a _(3)_ against nuclear missiles. Nowadays, they are used to _(4)_ targets. But apart from military uses, they have many applications in engineering, communications, medicine, and the arts.

In engineering, powerful laser _(5)_ can be focused on a small area. These beams can heat, melt, or vaporize material in a very precise way. They can be used for drilling diamonds, cutting complex shapes in materials from plastics to steel, for spot welding and for surfacing techniques, such as hardening aircraft engine turbine blades. Laser beams can also be used to _(6)_ and align structures.

Lasers are ideal for communications in space. Laser light can carry many more information _(7)_ than microwaves because of its high frequency. In addition, it can travel long distances without _(8)_ signal strength. Lasers can also be used for information recording and reading. Compact discs are read by lasers.

In medicine, laser beams can treat damaged _(9)_ in a fraction of a second without harming healthy tissue. They can be used in very precise eye operations.

In the arts, lasers can provide fantastic displays of light. Pop concerts are often _(10)_ by laser displays.

Theories of Matter

Matter is defined as the substance of objects that also takes up space and has mass. But matter also has various characteristics, so ancient scientists searched for a universal explanation for appearance, properties and behaviour of matter. One theory that explained some of the properties of matter is the Molecular Theory of Matter. This was followed by the Atomic Theory of Matter. There are still theories being developed that try to explain the true structure of matter in even more detail.

The original Molecular Theory of Matter stated that all matter consists of tiny particles called molecules. These particles are constantly moving and bouncing off each other like billiard balls. The Molecular Theory of Matter is also called the Kinetic Theory of Matter, because of the constant movement of the molecules. The motion of molecules is responsible for the phenomenon of heat. In other words, the faster the molecules are moving, the higher the temperature. When the molecules speed up or the material is heated sufficiently, the kinetic energy overcome the molecular attraction and the substance changes its state from a solid to a liquid. Likewise, when the kinetic energy of the molecules increases further, the material can change from a liquid to a gaseous state.

Molecules can be broken into smaller particles called atoms. The Atomic Theory of Matter states that all matter consists of extremely small particles called atoms. It was originally thought that atoms were the smallest possible particles, but that has since been proven incorrect. Atoms consist of even smaller particles called electrons, protons, and neutrons. A combination of protons and neutrons combine to form the nucleus of an atom. A popular model or picture of an atom that explains many of its properties and features is the solar system model of the atom. This model is also called the Bohr Model, named after Neils Bohr, who came up with the idea. It states that electrons rotate around the nucleus, similar to the planets revolving around the sun. The Atomic Theory explains electricity. When electrons break away from their nuclei, their motion results in electricity.

Since the Atomic Theory was formulated, many new particles have been discovered. The new theories concerning these particles and predicted particles attempts to explain every phenomena in physics. This is also called the Universal Theory of Matter. Also, there have been discovered that the proton and neutron themselves are made of even smaller particles, called quarks. These particles are then held together by particles called gluons. Finally, there is a theory that these sub-atomic particles are not particles at all, but really vibrating strings. The Quantum Theory of Matter states that at the very small sub-atomic distances, matter does not travel in continuous motion. Instead, it jumps from position to position in discrete or quantum leaps. This theory also states that particles spin in very discrete motion. The Uncertainty Principle states that with small particles, you cannot tell exactly where the particle and how fast it is going at the same time. The newest theory is that matter consists of tiny strings of material, instead of round balls. The String Theory seems to explain many phenomena for both large systems and at the quantum level. But many scientists claim that it is simply a mathematical exercise, since it cannot be proven or disproven.

(From Theories of Matter by Ron Kurtus)