Alexander Davydov (physicist)

{{Short description|Soviet Ukrainian physicist (1912–1993)}}

{{family name hatnote|Sergeevich|Davydov|lang=Eastern Slavic}}

{{Infobox scientist

|name = Alexander Sergeevich Davydov

|image = Alexander S. Davydov.jpg

|birth_name =

|birth_date = {{Birth date|df=yes|1912|12|26}}

|birth_place = Yevpatoria, Russian Empire

|death_date = {{Death date and age|df=yes|1993|2|19|1912|12|26}}

|death_place = Kiev, Ukraine

|citizenship = Soviet Union
Ukraine

|nationality =

|fields = Theoretical Physics
Biophysics

|workplaces = NASU Institute of Physics
Moscow State University

|alma_mater = Moscow State University

|doctoral_advisor =

|notable_students =

|known_for = Davydov splitting
Davydov soliton

|awards = Hero of Socialist Labour (1982)
Order of Lenin (1971, 1982)
Shevchenko National Prize (1969)
Lenin Prize (1966)
Medal "For Labour Valour" (1961)

}}

Alexander Sergeevich Davydov ({{langx|ru|Александр Сергеевич Давы́дов}}, {{langx|uk|Олекса́ндр Сергі́йович Дави́дов}}) (26 December 1912 – 19 February 1993) was a Soviet and Ukrainian physicist. Davydov graduated from Moscow State University in 1939. In 1963-1990 he was Director of Institute for Theoretical Physics of the Ukrainian Academy of Sciences.{{cite web

| author = International Academy of Quantum Molecular Science (IAQMS)

| title = Alexander S. Davydov

| url = http://www.iaqms.org/deceased/davydov.php

|accessdate=2011-08-15

}}

His main contributions were in theory of absorption, scattering and dispersion of the light in molecular crystals. In 1948, he predicted the phenomenon that is known as Davydov splitting or factor-group splitting, "the splitting of bands in the electronic or vibrational spectra of crystals due to the presence of more than one (interacting) equivalent molecular entity in the unit cell."{{cite book

| last1 = McNaught

| first1 = Alan D.

| last2 = Wilkinson

| first2 = Andrew

| year = 2019

| chapter = Davydov splitting (factor-group splitting)

| title = IUPAC Compendium of Chemical Terminology

| publisher = International Union of Pure and Applied Chemistry

| location = Research Triangle Park, North Carolina

| url = https://goldbook.iupac.org/terms/view/D01526

| doi = 10.1351/goldbook.D01526

}} In the period 1958–1960 he developed the theory of collective excited states in spherical and non-spherical nuclei, known as Davydov-Filippov Model and Davydov-Chaban Model.

In 1973, Davydov applied the concept of molecular solitons in order to explain the mechanism of muscle contraction in animals.{{cite journal

| author = Davydov AS

| title = The theory of contraction of proteins under their excitation

| journal = Journal of Theoretical Biology

| volume = 38

| pages = 559–569

| year = 1973

| doi = 10.1016/0022-5193(73)90256-7

| pmid = 4266326

| issue = 3

| bibcode = 1973JThBi..38..559D

}}

{{cite journal

| author = Davydov AS

| title = Quantum theory of muscular contraction

| journal = Biophysics

| volume = 19

| pages = 684–691

| year = 1974

}}

{{cite journal

| author = Davydov AS

| title = Solitons and energy transfer along protein molecules

| journal = Journal of Theoretical Biology

| volume = 66

| pages = 379–387

| year = 1977

| doi = 10.1016/0022-5193(77)90178-3

| pmid = 886872

| issue = 2

| bibcode = 1977JThBi..66..379D

}} He studied theoretically the interaction of intramolecular excitations or excess electrons with autolocal breaking of the translational symmetry. These excitations are now known as Davydov solitons.{{cite journal

| last1 = Scott

| first1 = Alwyn C.

| title = Davydov solitons in polypeptides

| journal = Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences

| volume = 315

| issue = 1533

| pages = 423–436

| year = 1985

| doi = 10.1098/rsta.1985.0049

| bibcode = 1985RSPTA.315..423S

| osti = 6443952

| s2cid = 86823456

| url = https://digital.library.unt.edu/ark:/67531/metadc1210664/

}}{{cite journal

| last1 = Brizhik

| first1 = Larissa S.

| title = Dynamical properties of Davydov solitons

| journal = Ukrainian Journal of Physics

| volume = 48

| issue = 7

| pages = 611–622

| year = 2003

| url = http://archive.ujp.bitp.kiev.ua/files/journals/48/7/480701p.pdf

}} In 1979, Davydov published the first textbook on quantum biology entitled "Biology and Quantum Mechanics" in Russian, which was then translated in English three years later.{{cite book

| last1 = Davydov

| first1 = Alexander S.

| title = Биология и Квантовая Механика [Biology and Quantum Mechanics]

| publisher = Naukova Dumka

| year = 1979

| location = Kiev

| language = Russian

| oclc = 6736440

}}{{cite book

| last1 = Davydov

| first1 = Alexander S.

| title = Biology and Quantum Mechanics

| publisher = Pergamon Press

| year = 1982

| location = Oxford

| oclc = 7875407

| isbn = 9780080263922

}}