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Planck's constant

(Encyclopedia)Planck's constant plängks [key], fundamental constant of the quantum theory. It is represented by the letter h and has a value of 6.62607 × 10−34 joule-second. The combination h/2π, denoted by h ...

nihilism

(Encyclopedia)nihilism nīˈəlĭzəm [key], theory of revolution popular among Russian extremists until the fall of the czarist government (1917); the theory was given its name by Ivan Turgenev in his novel Father...

Lorentz, Hendrik Antoon

(Encyclopedia)Lorentz, Hendrik Antoon hĕnˈdrək änˈtōn lōˈrĕnts [key], 1853–1928, Dutch physicist, a pioneer in formulating the relations between electricity, magnetism, and light. He was one of the first...

Kahneman, Daniel

(Encyclopedia)Kahneman, Daniel, 1934–, Israeli-American psychologist, b. Tel Aviv, Ph.D. Univ. of California, Berkeley, 1961. Born to Lithuanian parents, he spent his youth in France, and immigrated to what soon ...

natural rights

(Encyclopedia)natural rights, political theory that maintains that an individual enters into society with certain basic rights and that no government can deny these rights. The modern idea of natural rights grew ou...

Heisenberg, Werner

(Encyclopedia)Heisenberg, Werner vĕrˈnər hīˈzənbĕrk [key], 1901–76, German physicist. One of the founders of the quantum theory, he is best known for his uncertainty principle, or indeterminacy principle, ...

elementary particles

(Encyclopedia)CE5 elementary particles, the most basic physical constituents of the universe. The first subatomic particle to be discovered was the electron, identified in 1897 by J. J. Thomson. After the...

learning

(Encyclopedia)learning, in psychology, the process by which a relatively lasting change in potential behavior occurs as a result of practice or experience. Learning is distinguished from behavioral changes arising ...

e, in mathematics

(Encyclopedia)e, in mathematics, irrational number occurring widely in mathematics and science, approximately equal to the value 2.71828; it is the base of natural, or Naperian, logarithms. The number e is defined ...

meiosis

(Encyclopedia)CE5 Formation of sperm cells through meiosis meiosis mīŏˈsĭs [key], process of nuclear division in a living cell by which the number of chromosomes is reduced to half the original number. Meio...