quantum


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quantum

 [kwon´tum] (L.)
an elemental unit of energy; the amount emitted or absorbed at each step when energy is emitted or absorbed by atoms or molecules.

quan·tum

, pl.

quan·ta

(kwahn'tŭm, -tă),
1. A unit of radiant energy (Q) varying according to the frequency (ν) of the radiation.
2. A certain definite amount.
[L. how much]

quantum

/quan·tum/ (kwon´tum) pl. quan´ta   [L.] a unit of measure under the quantum theory (q.v.).

quan·tum

, pl. quanta (kwahn'tŭm, -tǎ)
1. A unit of radiant energy (ε) varying according to the frequency (ν) of the radiation.
2. A certain definite amount.
[L. how much]

quantum

  1. a quantity or amount.
  2. the minimum quantity in which a neurotransmitter is secreted.
  3. a unit of light.

photon 

The basic unit of radiant energy defined by the equation
E = hν
where h is Planck's constant (6.62 ✕ 10−34 joule ✕ second), ν the frequency of the light and E the energy difference carried away by the emission of a single photon of light. The term photon usually refers to visible light whereas the term quantum refers to other electromagnetic radiations. See quantum theory; wave theory; troland.

quan·tum

, pl. quanta (kwahn'tŭm, -tǎ)
Unit of radiant energy (Q) varying by frequency (ν) of radiation.
[L. how much]

quantum (kwon´təm),

n a discrete unit of electromagnetic energy or of a roentgen. A quantity becomes quantized when its magnitude is restricted to a discrete set of values as opposed to a continuous set of values.
quantum theory,

quantum

pl. quanta [L.] an elemental unit of energy; the amount emitted or absorbed at each step when energy is emitted or absorbed by atoms or molecules.

quantum theory
radiation and absorption of energy occur in quantities (quanta) which vary in size with the frequency of the radiation.
References in periodicals archive ?
n], n > 2} corresponded to the above mentioned values for pure quantum states while the two lowest quantum heights [z.
In the past several years, Freedman and Kitaev have joined forces to explore the promise of their model for what they call a topological quantum computer.
In a land where self-gratification has reached heights never dreamed of in ancient Rome, where selfe-steem is more important than being able to read, and where self-help requires no more effort than putting on a cassette, the myth of quantum consciousness is just what the shrink ordered.
In 1998, when Nie and Alivisatos first floated the idea of using quantum dots for studying cells, the technology was still young and rife with problems.
Entanglement and other quantum weirdness may boost the accuracy of radar, Global Positioning System (GPS) receivers, and other navigation devices.
Having matched our most successful campaign last year, we're confident that with the continued support of concerned corporate citizens such as Quantum, we will meet the needs of an even greater number of children this year.
With grants from NREL or support from industry or other sources, scientific teams in the United States and England are pursuing projects ranging from merging quantum dots with conventional photovoltaic technology to fashioning dots into a new form of light-sensitive matter.
His 1991 paper on entanglement-based quantum key distribution is the most cited paper in quantum cryptography.
Computer scientists can, in principle, take advantage of superposition and the wavelike nature of quantum particles.
Quantum will offer Decru DataFort FC-series and S-series appliances, including DataFort FC1020, the industry's first 10-port tape encryption appliance.
Scientists dare to dream, anyway--not only of quantum computers but also of linking them together into networks.