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In [[physics]], a '''quantum''' (plural: ''quanta'') is the minimum unit of any [[physical]] [[entity]] involved in an interaction. An example of an entity that is quantized is the [[energy]] transfer of [[elementary]] particles of [[matter]] (called [http://en.wikipedia.org/wiki/Fermions fermions]) and of [http://en.wikipedia.org/wiki/Photons photons] and other [http://en.wikipedia.org/wiki/Bosons bosons]. The [[word]] comes from the [[Latin]] "quantus", for "how much." Behind this, one finds the fundamental notion that a physical property may be "quantized", referred to as "quantization". This means that the magnitude can take on only certain discrete numerical values, rather than any value, at least within a range. There is a related term of quantum number.

In [[physics]], a '''quantum''' (plural: ''quanta'') is the minimum unit of any [[physical]] [[entity]] involved in an interaction. An example of an entity that is quantized is the [[energy]] transfer of [[elementary]] particles of [[matter]] (called [https://en.wikipedia.org/wiki/Fermions fermions]) and of [https://en.wikipedia.org/wiki/Photons photons] and other [https://en.wikipedia.org/wiki/Bosons bosons]. The [[word]] comes from the [[Latin]] "quantus", for "how much." Behind this, one finds the fundamental notion that a physical property may be "quantized", referred to as "quantization". This means that the magnitude can take on only certain discrete numerical values, rather than any value, at least within a range. There is a related term of quantum number.

A photon, for example, is a single quantum of [[light]], and may thus be referred to as a "light quantum". The [[energy]] of an [[electron]] bound to an [[atom]] (at rest) is said to be quantized, which results in the stability of atoms, and of [[matter]] in general.

A photon, for example, is a single quantum of [[light]], and may thus be referred to as a "light quantum". The [[energy]] of an [[electron]] bound to an [[atom]] (at rest) is said to be quantized, which results in the stability of atoms, and of [[matter]] in general.

As incorporated into the [[theory]] of [[quantum mechanics]], this is regarded by physicists as part of the fundamental framework for understanding and describing [[nature]] at the infinitesimal level, for the very [[practical]] [[reason]] that it works. It is "in the nature of things", not a more or less [[arbitrary]] [[human]] preference.

As incorporated into the [[theory]] of [[quantum mechanics]], this is regarded by physicists as part of the fundamental framework for understanding and describing [[nature]] at the infinitesimal level, for the very [[practical]] [[reason]] that it works. It is "in the nature of things", not a more or less [[arbitrary]] [[human]] preference.[https://en.wikipedia.org/wiki/Quanta]

The [[concept]] of quantization was [[discovered]] in 1900 by German physicist [https://en.wikipedia.org/wiki/Max_Planck Max Planck], who had been trying to [[understand]] the emission of [[radiation]] from [[heat]]ed objects, known as [https://en.wikipedia.org/wiki/Black_body_radiation black body radiation]. By [[assuming]] that [[energy]] can only be absorbed or released in tiny, differential, [[discrete]] packets he called "quanta," Planck accounted for the [[fact]] that certain objects [[change]] [[color]] when heated. On December 14, 1900, Planck reported his [[revolutionary]] findings about quanta to the German Physical Society and introduced the [[idea]] of quantization for the first time as a part of his [[research]] on black body radiation. As a result of his [[experiments]], Planck deduced the [[numerical]] [[value]] of h, known as the [https://en.wikipedia.org/wiki/Planck_constant Planck constant], and could also report a more precise [[value]] for the [https://en.wikipedia.org/wiki/Avogadro%27s_number Avogadro-Loschmidt number], the number of real [[molecules]] in a [https://en.wikipedia.org/wiki/Mole_(unit) mole], and the [[unit]] of [[electrical]] charge, to the German Physical Society. After his [[theory]] was [[validated]], Planck was awarded the [[Nobel Prize]] in Physics in 1918 for his [[discovery]].

==References==

==References==

# Real-World Quantum Effects Demonstrated February 11, 2005

# [https://www.scienceagogo.com/news/20050110221715data_trunc_sys.shtml Real-World Quantum Effects Demonstrated] February 11, 2005

 

==Further Reading==

==Further Reading==

* B. Hoffmann, The Strange Story of the Quantum, Pelican 1963.

* B. Hoffmann, The Strange Story of the Quantum, Pelican 1963.