Spin–orbit interactionIn quantum physics, the spin–orbit interaction (also called spin–orbit effect or spin–orbit coupling) is a relativistic interaction of a particle's spin with its motion inside a potential. A key example of this phenomenon is the spin–orbit interaction leading to shifts in an electron's atomic energy levels, due to electromagnetic interaction between the electron's magnetic dipole, its orbital motion, and the electrostatic field of the positively charged nucleus.
Spin-1/2In quantum mechanics, spin is an intrinsic property of all elementary particles. All known fermions, the particles that constitute ordinary matter, have a spin of 1/2. The spin number describes how many symmetrical facets a particle has in one full rotation; a spin of 1/2 means that the particle must be rotated by two full turns (through 720°) before it has the same configuration as when it started. Particles having net spin 1/2 include the proton, neutron, electron, neutrino, and quarks.
Komi alphabetsThe Komi language, a Uralic language spoken in the north-eastern part of European Russia, has been written in several different alphabets. Currently, Komi writing uses letters from the Cyrillic script. There have been five distinct stages in the history of Komi writing: 14th to 17th centuries — Anbur, the original graphic system; 18th century to 1918 — based on the early Cyrillic alphabet; 1918 to 1932 and 1936 to 1938 — Vasily Molodtsov's alphabet based on the modified Cyrillic alphabet; 1932 to 1936 — Latinization of the alphabet; since 1938 — modern script based on the Cyrillic alphabet.
X-ray tubeAn X-ray tube is a vacuum tube that converts electrical input power into X-rays. The availability of this controllable source of X-rays created the field of radiography, the imaging of partly opaque objects with penetrating radiation. In contrast to other sources of ionizing radiation, X-rays are only produced as long as the X-ray tube is energized. X-ray tubes are also used in CT scanners, airport luggage scanners, X-ray crystallography, material and structure analysis, and for industrial inspection.
Self-adjoint operatorIn mathematics, a self-adjoint operator on an infinite-dimensional complex vector space V with inner product (equivalently, a Hermitian operator in the finite-dimensional case) is a linear map A (from V to itself) that is its own adjoint. If V is finite-dimensional with a given orthonormal basis, this is equivalent to the condition that the matrix of A is a Hermitian matrix, i.e., equal to its conjugate transpose A^∗. By the finite-dimensional spectral theorem, V has an orthonormal basis such that the matrix of A relative to this basis is a diagonal matrix with entries in the real numbers.
Ukrainian alphabetThe Ukrainian alphabet (abetka, azbuka alfavit) is the set of letters used to write Ukrainian, which is the official language of Ukraine. It is one of several national variations of the Cyrillic script. It comes from the Cyrillic script, which was devised in the 9th century for the first Slavic literary language, called Old Slavonic. In the 10th century, it became used in Kievan Rus' to write Old East Slavic, from which the Belarusian, Russian, Rusyn, and Ukrainian alphabets later evolved.
Nikolai Rumyantsev (historian)Nikolai Vasilyevich Rumyantsev (Николай Васильевич Румянцев, 1892–1956) was a Soviet author of several polemics on the history of Christianity, translator. He was also a member of the Soviet circle "Atheist" and the League of Militant Atheists. In the 1920s Rumyantsev was one of the leading proponents of the so-called mythological school in the Soviet academia.
Om mani padme hum(ॐ मणि पद्मे हूँ, õːː mɐɳɪ pɐdmeː ɦũː) is the six-syllabled Sanskrit mantra particularly associated with the four-armed Shadakshari form of Avalokiteshvara, the bodhisattva of compassion. It first appeared in the Mahayana Kāraṇḍavyūhasūtra where it is also referred to as the sadaksara (six syllabled) and the paramahrdaya, or “innermost heart” of Avalokiteshvara. In this text the mantra is seen as the condensed form of all Buddhist teachings. The precise meaning and significance of the words remains much discussed by Buddhist scholars.
Oleg TrubachyovOleg Nikolayevich Trubachyov (also transliterated as Trubachev or Trubačev, Оле́г Никола́евич Трубачёв; 23 October 1930, in Stalingrad – 9 March 2002, in Moscow) was a Soviet and Russian linguist. A researcher of the etymology of Slavic languages and Slavic onomastics, specialist in historical linguistics and lexicographer. He was a Doctor of Sciences in Philological Sciences, an academician of the Russian Academy of Sciences and served as the editor-in-chief of the Etimologiya yearbook.
Kalmyk OiratKalmyk Oirat (Хальмг Өөрдин келн, Haľmg Öördin keln, xaljˈmək øːrˈdin keˈlən), commonly known as the Kalmyk language (Хальмг келн, Haľmg keln, xaljˈmək keˈlən), is a variety of the Oirat language, natively spoken by the Kalmyk people of Kalmykia, a federal subject of Russia. In Russia, it is the standard form of the Oirat language (based on the Torgut dialect), which belongs to the Mongolic language family. The Kalmyk people of the Northwest Caspian Sea of Russia claim descent from the Oirats from Eurasia, who have also historically settled in Mongolia and Northwest China.
Andrey VoronikhinAndrey (Andrei) Nikiforovich Voronikhin (Андрей Никифорович Воронихин) (28 October 1759, Novoe Usolye, Perm Oblast – 21 February 1814, Saint Petersburg) was a Russian architect and painter. As a representative of classicism he was also one of the founders of the monumental Russian Empire style. Born a serf of the Stroganov family, he is best known for his work on Kazan Cathedral in Saint Petersburg. Andrey Voronikhin was born in the village of Novoa Usolye (now Perm Krai) to a family who were the serfs of count Alexander Sergeyevich Stroganov, a longtime President of the Imperial Academy of Arts.
Russian spelling rulesIn Russian, the term spelling rule is used to describe a number of rules relating to the spelling of words in the language that would appear in most cases to deviate from a strictly phonetic transcription. All the spelling rules found in the Russian language dictate that certain consonants cannot be followed either under any circumstance or in an unstressed syllable by certain vowels. In most cases where spelling rules exist, they do not actually affect the pronunciation.
