Editing Correspondence principle (section)

{{Short description|Physics principle formulated by Niels Bohr}}
{{Other uses}}
In [[physics]], a '''correspondence principle''' is any one of several premises or assertions about the relationship between [[classical mechanics|classical]] and [[quantum mechanics]]. 
The physicist [[Niels Bohr]] coined the term in 1920<ref>{{Citation |last=Bohr |first=N. |title=Über die Serienspektra der Elemente |journal=Zeitschrift für Physik |volume=2 |issue=5 |pages=423–478 |year=1920 |trans-title=About the serial spectra of the elements |url=https://zenodo.org/record/2051363 |language=de |bibcode=1920ZPhy....2..423B |doi=10.1007/BF01329978 |s2cid=121792424 |author-link=Niels Bohr}} (English translation in {{Cite book |last=Udden |first=A. D. |url=https://linkinghub.elsevier.com/retrieve/pii/S1876050308700938 |title=IX. On The Series Spectra of The Elements |date=1976 |publisher=Elsevier |isbn=978-0-7204-1803-3 |volume=3 |pages=241–282 |language=en |doi=10.1016/s1876-0503(08)70093-8}})</ref> during the [[old quantum theory|early development of quantum theory]]; he used it to explain how quantized classical orbitals connect to quantum radiation.<ref name="SEP">{{cite SEP |url-id=bohr-correspondence |title=Bohr's Correspondence Principle |author-last=Bokulich |author-first=Alisa |date=2020-08-13}}</ref> 
Modern sources often use the term for the idea that the behavior of systems described by quantum theory reproduces classical physics in the limit of large [[quantum numbers]]: for large [[orbit]]s and for large [[energy|energies]], quantum calculations must agree with classical calculations.<ref name="Tipler">{{cite book |last1=Tipler |first1=Paul |last2=Llewellyn |first2=Ralph |title=Modern Physics |edition=5 |year=2008 |publisher=[[W. H. Freeman and Company]] |isbn=978-0-7167-7550-8 |pages=160–161}}</ref> A "generalized" correspondence principle refers to the requirement for a broad set of connections between any old and new theory.