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quantum quantity |
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Kinds of quantum quantity :
- atomic mass number (3 facts) - The total number of protons and neutrons in an atom's nucleus. For example, oxygen-16 has a mass number of sixteen, because it has eight protons and eight neutrons.
- atomic number (7 facts) (charge number) - The number of protons in an atom's nucleus. This determines the type of element.
- azimuthal quantum number (3 facts) (k) - A measure of the minor axis of an elliptic orbital of an electron according to the Bohr-Sommerfeld theory.
- chirality (4 facts) (chiral) - Feature of fundamental particle physics that distinguishes left- from right-handed, showing that the universe is not fully left-right symmetric., An expression of the basic handedness of nature. Fundamental theories of the elementary particles and of superstrings must possess chirality.
- flavor (5 facts) - The term used to describe different quark types. There are six quark flavors: up, down, strange, charm, bottom and top., Designation of quark types - up down, strange, charmed, top, and bottom. Flavor determines how the weak nuclear force influences quarks., The known quarks exist in six different types, or flavors: up, down, charmed, strange, top, and bottom. The up and down quarks belong to the first generation, the charmed and strange quarks belong to the second, and the top and bottom quarks belong to the third. The up, charmed, and top quarks each have an electrical charge 2/3 that of a proton, while the down, strange, and bottom quarks have a charge -1/3 that of a proton. See Table 7.1 on page 120., In particle physics, another word for "type". For example, there are 6 flavors of quarks, meaning that there are 6 different types of quarks.
- quark color (4 facts) - An attribute which distinguishes otherwise identical quarks of the same flavor. Three colors red, green and blue - are required to distinguish the three valence quarks of which baryons are composed. It must be stressed that these colors are just labels and have nothing to do with ordinary color. Color is the source of the strong force which binds quarks together inside baryons and mesons, and so the three colors (r, g, b) can be thought of as three different color charges analogous to electric charge., Each flavor of quark can exist in three variations, called colors, usually labeled as red, green, and blue. The color of a quark has no relation to its visual appearance, but the word color is used because there are three variations, in analogy with the three primary colors. Measurable properties of the quarks, such as electric charge and mass, depend on the flavor but not the color, but the color is responsible for the interactions that bind the quarks together (see Yang-Mills theories). Individual quarks cannot exist independently, but are forever confined within baryons or mesons, each of which is colorless. Baryons achieve colorlessness by being composed of three quarks, one of each color, while mesons achieve colorlessness by pairing each colored quark with its corresponding antiquark., Property of quarks that expresses their behavior under the strong force. Analogous to the concept of charge in electromagnetism, except that, whereas there are two electrical charges (plus and minus), the strong force involves three color charges - red, green, and blue. The term is whimsical, and has nothing to do with color in the conventional sense, any more than quark "flavor", which determines the weak force behavior of quarks, has anything to do with taste.
- spin (5 facts) - A quantum property of all particles which denotes the intrinsic angular momentum of the particle., The intrinsic angular momentum possessed by many particles. It can be thought of as resulting from the particles spinning about an axis through their centers. In contrast to orbital angular momentum, spin is quantized in integer and half-integer units of h bar. Fundamentally, spin describes how quantum fields transform under the transformations of special relativity., A quantum-mechanical version of the familiar notion of the same name; particles have an intrinsic amount of spin that is either a whole number or half a whole number (in multiples of Plancks constant), and which never changes., The intrinsic angular momentum of an elementary particle, as by the particle's spinning on its axis. Spin is quantized in units of Planck's constant of action, h, so that, e.g., "spin 1," means spin = 1h. Particles with integral spin (0, 1) are called bosons; those with half spin are fermions.