Проверьте, знаете ли Вы следующие слова и словосочетания для понимания текста.
а) Найдите в правой колонке русские эквиваленты:
1. to make up 1. ударяться, наталкиваться
2. to bump 2. взаимодействовать, влиять друг на друга
3. to interact 3. составлять
4. composite particle 4. несовместимый
5. rest mass 5. составная частица
6. incompatible 6. масса покоя
б) Найдите в правой колонке английские эквиваленты:
1. обнаруживать, открывать 1. to equate
2. спутывать 2. to reveal
3. приравнивать 3. to contemplate
4. переход, превращение 4. to confuse
5. рассматривать 5. relativity
6. относительность 6. conversion
MATTER
Before the 20th century, the term matter included ordinary matter composed of atoms and excluded other energy phenomena such as light or sound. This concept of matter may be generalized from atoms to include any objects having mass even when at rest, matter does not have a universal definition, nor a fundamental concept in physics today. Matter is also used loosely as a general term for the substance that makes up all observable physical objects.
All the objects from everyday life that we can bump into, touch or squeeze are composed of atoms. This atomic matter is made up of interacting subatomic particles - usually a nucleus of protons and neutrons, and a cloud of orbiting electrons. Typically, science considers these composite particles matter because they have both rest mass and volume. By contrast, massless particles, such as photons, are not considered matter, because they have neither rest mass nor volume.
Different fields of science use the term matter in different, and sometimes incompatible, ways. There is no single universally agreed scientific meaning of the word "matter". Scientifically, the term "mass" is well-defined, but "matter" is not. Sometimes in the field of physics "matter" is simply equated with particles that exhibit rest mass, (that cannot travel at the speed of light), such as quarks and leptons.
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Nevertheless, quarks and leptons together make up "ordinary matter", and their interactions contribute to the effective volume of the composite particles that make up ordinary matter.
Matter commonly exists in four states (or phases): solid, liquid and gas, and plasma. However, advances in experimental techniques have revealed other previously theoretical phases, such as Bose-Einstein condensates and fermionic condensates. A focus on an elementary-particle view of matter also leads to new phases of matter, such as the quark-gluon plasma. For much of the history of the natural sciences people have contemplated the exact nature of matter.
Matter should not be confused with mass, as the two are not quite the same in modern physics. For example, mass is a conserved quantity, which means that its value is unchanging through time, within closed systems. However, matter is not conserved in such systems, although this is not obvious in ordinary conditions on the Earth, where matter is approximately conserved. Still, special relativity shows that matter may disappear by conversion into energy, within such systems. However, as mass (like energy) can neither be created nor destroyed, the quantity of mass and the quantity of energy remain the same during a transformation of matter (which represents a certain amount of energy) into non-material (i.e. non-matter) energy. This is also true in the reverse transformation of energy into matter.
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