View source for André-Marie Ampère

{{Short description|French physicist and mathematician (1775–1836)}}
{{For|the microarchitecture|Ampere (microarchitecture)}}
{{Use dmy dates|date=August 2020}}
{{Infobox scientist
| honorific_suffix  = {{post-nominals|country=GBR|size=100%|ForMemRS}}
| image             = Ampere Andre 1825.jpg
| caption           = Engraving of Ampère by [[Ambroise Tardieu]], 1825
| birth_date        = {{birth date|df=y|1775|1|20}}
| birth_place       = [[Lyon]], [[Kingdom of France]]
| death_date        = {{death date and age|df=yes|1836|6|10|1775|1|20}}
| death_place       = [[Marseille]], [[July Monarchy|Kingdom of France]]
| known_for         = {{plainlist|
*[[Fluorine#Early discoveries|Discovering fluorine]]
*[[Ampère's circuital law]]
*[[Ampère's force law]]
*[[Right-hand rule#Ampère's right-hand grip rule|Ampère's right hand grip rule]]
*[[Magnetic moment#Amperian loop model|Ampèrian loop model]]
*[[Monge–Ampère equation]]
*[[Avogadro's law|Avogadro–Ampère hypothesis]]
*[[Needle telegraph]]
*[[Solenoid]]
}}
| awards            = [[Fellow of the Royal Society#Foreign member|ForMemRS]] (1827)
| fields            = [[Physics]]<br>[[Mathematics]]
| work_institutions = [[École polytechnique]]<br>[[Collège de France]]
| signature         = André-Marie Ampère signature.svg
}}
{{Electromagnetism|Scientists}}

'''André-Marie Ampère''' ({{IPAc-en|UK|ˈ|æ|m|p|ɛər}}, {{IPAc-en|US|ˈ|æ|m|p|ɪər}};<ref>[http://dictionary.reference.com/browse/ampere "Ampère"]. ''[[Random House Webster's Unabridged Dictionary]].''</ref> {{IPA|fr|ɑ̃dʁe maʁi ɑ̃pɛʁ|lang}}; 20 January 1775{{snd}}10 June 1836)<ref>{{cite book|title=Dictionary of Scientific Biography|url=https://archive.org/details/dictionaryofsci001gill|url-access=registration|year=1970|publisher=Charles Scribner's Sons|location=United States of America|isbn=9780684101149}}</ref> was a French [[physicist]] and [[mathematician]] who was one of the founders of the science of [[classical electromagnetism]], which he referred to as ''electrodynamics''. He is also the inventor of numerous applications, such as the [[solenoid]] (a term coined by him) and the [[electrical telegraph]]. As an [[Autodidacticism|autodidact]], Ampère was a member of the [[French Academy of Sciences]] and professor at the [[École polytechnique]] and the [[Collège de France]].

The [[International System of Units|SI]] unit of [[electric current]], the [[ampere]] (A), is named after him. His name is also one of the [[List of the 72 names on the Eiffel Tower|72 names inscribed]] on the [[Eiffel Tower]]. The term ''kinematic'' is the English version of his ''cinématique'',<ref>{{cite book |last=Ampère |first=André-Marie |author-link=André-Marie Ampère |url=https://archive.org/details/bub_gb_j4QPAAAAQAAJ |title=Essai sur la Philosophie des Sciences |publisher=Chez Bachelier |year=1834}}</ref> which he constructed from the [[Ancient Greek language|Greek]] {{lang|grc|κίνημα}} ''kinema'' ("movement, motion"), itself derived from {{lang|grc|κινεῖν}} ''kinein'' ("to move").<ref>{{cite book |last=Merz |first=John |url=https://archive.org/details/historyofeuropea02merzuoft |title=A History of European Thought in the Nineteenth Century |publisher=Blackwood, London |year=1903 |pages=[https://archive.org/details/historyofeuropea02merzuoft/page/5 5]}}</ref><ref name="Bottema">{{cite book |author=O. Bottema & B. Roth |url=https://books.google.com/books?id=f8I4yGVi9ocC |title=Theoretical Kinematics |publisher=Dover Publications |year=1990 |isbn=0-486-66346-9 |at=preface, p. 5}}</ref>

== Biography ==

=== Early life ===
André-Marie Ampère was born on 20 January 1775 in Lyon to Jean-Jacques Ampère, a prosperous businessman, and Jeanne Antoinette Desutières-Sarcey Ampère, during the height of the [[French Enlightenment]]. He spent his childhood and adolescence at the family property at [[Poleymieux-au-Mont-d'Or]] near Lyon.<ref>{{cite web |url=http://www.ieeeghn.org/wiki/index.php/Andre-Marie_Ampere |title=Andre-Marie Ampere |work=IEEE Global History Network |publisher=IEEE |access-date=21 July 2011}}</ref> Jean-Jacques Ampère, a successful merchant, was an admirer of the philosophy of [[Jean-Jacques Rousseau]], whose theories of education (as outlined in his treatise ''[[Emile, or On Education|Émile]]'') were the basis of Ampère's education. Rousseau believed that young boys should avoid formal schooling and pursue instead a "direct education from nature." Ampère's father actualized this ideal by allowing his son to educate himself within the walls of his well-stocked library. French Enlightenment masterpieces such as [[Georges Louis Leclerc, Count of Buffon|Georges-Louis Leclerc, comte de Buffon]]'s ''Histoire naturelle, générale et particulière'' (begun in 1749) and [[Denis Diderot]] and [[Jean le Rond d'Alembert]]'s ''[[Encyclopédie]]'' (volumes added between 1751 and 1772) thus became Ampère's schoolmasters.{{Citation needed|date=June 2017}} The young Ampère, however, soon resumed his [[Latin]] lessons, which enabled him to master the works of [[Leonhard Euler]] and [[Daniel Bernoulli]].<ref name="EB1911">{{EB1911|inline=y|wstitle=Ampère, André Marie|volume=1|pages=878–879}}</ref>

=== French Revolution ===
In addition, Ampère used his access to the latest books to begin teaching himself advanced mathematics at age 12. In later life Ampère claimed that he knew as much about mathematics and science when he was eighteen as ever he knew, but as a [[polymath]], his reading embraced history, travels, poetry, philosophy, and the natural sciences.<ref name="EB1911"/> His mother was a devout Catholic, so Ampère was also initiated into the [[Catholicism|Catholic faith]] along with Enlightenment science. The [[French Revolution]] (1789–99) that began during his youth was also influential: Ampère's father was called into [[Civil service|public service]] by the new revolutionary government,<ref>{{cite web|url=http://simplyknowledge.com/popular/biography/andre-marie-ampere |title=Biography of Andre Marie Ampere|access-date=2019-09-03}}</ref> becoming a local judge (''juge de paix'') in a small town near Lyon. When the [[Jacobin]] faction seized control of the Revolutionary government in 1792, his father Jean-Jacques Ampère resisted the new political tides, and he was [[guillotine]]d on 24 November 1793, as part of the [[Jacobin#The Terror|Jacobin purges]] of the period.

In 1796, Ampère met Julie Carron and, in 1799, they were married. Ampère took his first regular job in 1799 as a [[mathematics]] teacher, which gave him the financial security to marry Carron and father his first child, [[Jean-Jacques Ampère|Jean-Jacques]] (named after his father), the next year. (Jean-Jacques Ampère eventually achieved his own fame as a scholar of languages.) Ampère's maturation corresponded with the transition to the [[Napoleonic era|Napoleonic regime]] in France, and the young father and teacher found new opportunities for success within the technocratic structures favoured by the new French [[Napoleon|First Consul]]. In 1802, Ampère was appointed a professor of [[physics]] and [[chemistry]] at the École Centrale in [[Bourg-en-Bresse]], leaving his ailing wife and infant son in Lyon. He used his time in Bourg to research mathematics, producing ''Considérations sur la théorie mathématique du jeu'' (1802; "Considerations on the Mathematical Theory of Games"), a treatise on [[Probability theory|mathematical probability]] that he sent to the [[Paris Academy of Sciences]] in 1803.

=== Teaching career ===
[[File:Ampère - Essai sur la philosophie des sciences, 1838 - 3912601 323893 1 00011.tif|thumb|''Essai sur la philosophie des sciences'']]
After the death of his wife in July 1803,<ref>Ampère married again after his much loved first wife died, but his second marriage was very unhappy and ended in divorce.</ref><ref>{{cite book|last1=Laidler|first1=Keith J.|title=To Light such a Candle|date=1993|publisher=Oxford University Press|page=128}}
</ref> Ampère moved to Paris, where he began a tutoring post at the new [[École Polytechnique]] in 1804. Despite his lack of formal qualifications, Ampère was appointed a professor of mathematics at the school in 1809. As well as holding positions at this school until 1828, in 1819 and 1820 Ampère offered courses in [[philosophy]] and [[astronomy]], respectively, at the [[University of Paris]], and in 1824 he was elected to the prestigious chair in [[experimental physics]] at the [[Collège de France]]. In 1814, Ampère was invited to join the class of mathematicians in the new ''Institut Impérial'', the umbrella under which the reformed state Academy of Sciences would sit.

Ampère engaged in a diverse array of scientific inquiries during the years leading up to his election to the academy—writing papers and engaging in topics from mathematics and philosophy to chemistry and astronomy, which was customary among the leading scientific intellectuals of the day. Ampère claimed that "at eighteen years he found three culminating points in his life, his [[First Communion]], the reading of Antoine Leonard Thomas's "Eulogy of Descartes", and the [[Taking of the Bastille]]. On the day of his wife's death he wrote two verses from the [[Psalm]]s, and the prayer, 'O Lord, God of Mercy, unite me in Heaven with those whom you have permitted me to love on earth.' In times of duress he would take refuge in the reading of the [[Bible]] and the [[Fathers of the Church]]."<ref>{{cite web | title = Catholic Encyclopedia | url = http://www.newadvent.org/cathen/01437c.htm| access-date = 29 December 2007 }}</ref>

A lay [[List of lay Catholic scientists|Catholic]], he took for a time into his family the young student [[Frédéric Ozanam]] (1813–1853), one of the founders of the [[Conference of Charity]], later known as the [[Society of Saint Vincent de Paul]].<ref name="gregory_ozanam">{{cite journal |last1=Gregory |first1=David L. |title=Antoine Frederic Ozanam: Building the Good Society |journal=St. Thomas Law Journal |date=2005 |volume=3 |issue=1 |pages=21–48}}</ref> Ozanam would much later be [[Beatification|beatified]] by [[Pope John Paul II]] in 1998. Through Ampère, Ozanam had contact with leaders of the neo-Catholic movement, such as [[François-René de Chateaubriand]], [[Jean-Baptiste Henri Lacordaire]], and [[Charles Forbes René de Montalembert]].<ref name="gregory_ozanam"/>

===Work in electromagnetism===

In September 1820, Ampère's friend and eventual eulogist [[François Arago]] showed the members of the French Academy of Sciences the surprising discovery by [[Denmark|Danish]] physicist [[Hans Christian Ørsted]] that a [[Compass|magnetic needle]] is deflected by an adjacent [[electric current]]. Ampère began developing a mathematical and physical theory to understand the relationship between [[electricity]] and [[magnetism]]. Furthering Ørsted's experimental work, Ampère showed that two parallel wires carrying electric currents attract or repel each other, depending on whether the currents flow in the same or opposite directions, respectively - this laid the foundation of electrodynamics. He also applied mathematics in generalizing physical laws from these experimental results. The most important of these was the principle that came to be called [[Ampère's force law|Ampère's law]], which states that the mutual action of two lengths of current-carrying wire is proportional to their lengths and to the intensities of their currents. Ampère also applied this same principle to magnetism, showing the harmony between his law and French physicist [[Charles Augustin de Coulomb]]'s law of electric action. Ampère's devotion to, and skill with, experimental techniques anchored his science within the emerging fields of experimental physics.

Ampère also provided a physical understanding of the electromagnetic relationship, theorizing the existence of an "electrodynamic molecule" (the forerunner of the idea of the [[electron]]) that served as the component element of both electricity and magnetism. Using this physical explanation of electromagnetic motion, Ampère developed a physical account of electromagnetic phenomena that was both empirically demonstrable and mathematically predictive. Almost 100 years later, in 1915, [[Albert Einstein]] together with [[Wander Johannes de Haas]] made the proof of the correctness of Ampère's hypothesis through the [[Einstein–de Haas effect]]. In 1827, Ampère published his magnum opus, ''Mémoire sur la théorie mathématique des phénomènes électrodynamiques uniquement déduite de l'experience'' (Memoir on the Mathematical Theory of Electrodynamic Phenomena, Uniquely Deduced from Experience), the work that coined the name of his new science, ''electrodynamics'', and became known ever after as its founding treatise.

In 1827, Ampère was elected a [[Foreign Member of the Royal Society]] and in 1828, a foreign member of the [[Royal Swedish Academy of Science]].<ref>{{cite web |title=Library and Archive Catalogue |url=http://www2.royalsociety.org/DServe/dserve.exe?dsqIni=Dserve.ini&dsqApp=Archive&dsqCmd=Show.tcl&dsqDb=Persons&dsqPos=0&dsqSearch=%28Surname%3D%27ampere%27%29 |access-date=13 March 2012 |publisher=Royal Society}}</ref> Probably the highest recognition came from [[James Clerk Maxwell]], who in his ''[[Treatise on Electricity and Magnetism]]'' named Ampère "the Newton of electricity".{{citation needed|date=December 2022}}

== Honours ==
* '''8.10.1825''': Member of the [[Royal Academy of Science, Letters and Fine Arts of Belgium]].<ref>Index biographique des membres et associés de l'Académie royale de Belgique (1769–2005) p. 15</ref>

===Legacy===
An international convention, signed at the 1881 [[International Exposition of Electricity]], established the [[Ampere (unit)|ampere]] as one of the standard units of electrical measurement, in recognition of his contribution to the creation of modern electrical science and along with the [[coulomb]], [[volt]], [[ohm]], [[watt]] and [[farad]], which are named, respectively, after Ampère's contemporaries [[Charles-Augustin de Coulomb]] of France, [[Alessandro Volta]] of [[Italy]], [[Georg Ohm]] of [[Germany]], [[James Watt]] of [[Scotland]] and [[Michael Faraday]] of England. Ampère's name is one of the [[List of the 72 names on the Eiffel Tower|72 names inscribed on the Eiffel Tower]].

Many streets and [[Place Ampère|squares]] are named after Ampère, as are [[Collège-lycée Ampère|schools]], a [[List of Lyon Metro stations#Line A|Lyon metro station]], a [[graphics processing unit]] [[Ampere (microarchitecture)|microarchitecture]], a [[List of mountains on the Moon|mountain on the moon]] and an [[MV Ampere|electric ferry]] in Norway.<ref>{{cite web|url=http://www.tu.no/artikler/batterifergen-har-mattet-sta-over-avganger-na-er-losningen-klar/364633 |title=Batterifergen har måttet stå over avganger. Nå er løsningen klar|work=[[Teknisk Ukeblad]] |access-date=19 November 2016|date= November 2016}}</ref>

==Writings==
* ''Considérations sur la théorie mathématique du jeu'', [[Perisse Frères|Perisse]], Lyon Paris 1802, [https://archive.org/details/considerationssu00ampuoft online lesen] im [[Internet Archive|Internet-Archiv]]
* {{citation|surname1=André-Marie Ampère|title=Recueil d'observations électro-dynamiques: contenant divers mémoires, notices, extraits de lettres ou d'ouvrages périodiques sur les sciences, relatifs a l'action mutuelle de deux courans électriques, à celle qui existe entre un courant électrique et un aimant ou le globe terrestre, et à celle de deux aimans l'un sur l'autre|publisher=Chez Crochard|year=1822|language=fr|url={{Google books|-EZOso9TN70C|plainurl=y|page=1}}|access-date=2010-09-26}}
* {{citation|surname1=André-Marie Ampère|surname2=Babinet (Jacques, M.)|title=Exposé des nouvelles découvertes sur l'électricité et le magnétisme |publisher=Chez Méquignon-Marvis|year=1822|language=de|url={{Google books|tBoAAAAAQAAJ|plainurl=y}}|access-date=2010-09-26}}
* {{citation|surname1=André-Marie Ampère|title=Description d'un appareil électro-dynamique |publisher=Chez Crochard … et Bachelie|year=1824|language=fr|url={{Google books|-dsEAAAAYAAJ|plainurl=y}}|access-date=2010-09-26}}
* {{citation|surname1=André-Marie Ampère|title=Théorie des phénomènes électro-dynamiques, uniquement déduite de l'expérience |publisher=Méquignon-Marvis|year=1826|language=fr|url={{Google books|LzcVAAAAQAAJ|plainurl=y}}|access-date=2010-09-26}}
** {{citation|surname1=André-Marie Ampère|title=Théorie mathématique des phénomènes électro-dynamiques: uniquement déduite de l'expérience |publisher=A. Hermann|year=1883|edition=2nd|language=fr|url=https://archive.org/details/thoriemathmatiq00ampgoog|access-date=2010-09-26}}
* {{citation|surname1=André-Marie Ampère|title=Essai sur la philosophie des sciences, ou, Exposition analytique d'une classification naturelle de toutes les connaissances humaines |publisher=Chez Bachelier|year=1834|language=de|url={{Google books|j4QPAAAAQAAJ|plainurl=y}}|access-date=2010-09-26}}
** {{citation|surname1=André-Marie Ampère|title=Essai sur la philosophie des sciences |volume=Bd. 1|publisher=Chez Bachelier|year=1834|language=de|url={{Google books|OPcOAAAAQAAJ|plainurl=y}}|access-date=2010-09-26}}
** {{citation|surname1=André-Marie Ampère|title=Essai sur la philosophie des sciences |volume=Bd. 2|publisher=Bachelier|year=1843|language=de|url={{Google books|ltAEAAAAYAAJ|plainurl=y}}|access-date=2010-09-26}}
Partial translations:
* Magie, W.M. (1963). ''A Source Book in Physics.'' Harvard: Cambridge MA. pp.&nbsp;446–460.
* {{cite book|title=The Tests of Time: Readings in the Development of Physical Theory|year=2003|publisher=Princeton University Press|location=Princeton|isbn=978-0691090856|pages=157–162|editor1=Lisa M. Dolling |editor2=Arthur F. Gianelli |editor3=Glenn N. Statile }}.
Complete translations:
*{{Cite book| publisher = Apeiron | last = Ampère| first = André-Marie |editor=André Koch Torres Assis |translator=J. P. M. C Chaib | title = Ampère's electrodynamics: analysis of the meaning and evolution of Ampère's force between current elements, together with a complete translation of his masterpiece: Theory of electrodynamic phenomena, uniquely deduced from experience| location = Montreal| date = 2015 | url=https://www.ifi.unicamp.br/~assis/Amperes-Electrodynamics.pdf |archive-url=https://ghostarchive.org/archive/20221009/https://www.ifi.unicamp.br/~assis/Amperes-Electrodynamics.pdf |archive-date=2022-10-09 |url-status=live | isbn=978-1-987980-03-5}}
*{{Cite book| last = Ampère| first = André-Marie| others = Michael D. Godfrey, Stanford University, (trans.)| title = Mathematical Theory of Electrodynamic Phenomena, Uniquely Derived from Experiments| date = 2015 | url=https://docs.google.com/file/d/0BzMHTgCmyrNZSVFCZkpXNTMwQU0/edit}}

==References==
{{Reflist}}

==Further reading==
* {{cite encyclopedia | last = Williams | first = L. Pearce | title = Ampère, André-Marie | encyclopedia = [[Dictionary of Scientific Biography]] | volume = 1 | pages = 139–147  | publisher = Charles Scribner's Sons | location = New York | year=  1970 | isbn = 978-0-684-10114-9}}
* {{cite book|title=André-Marie Ampère|first=James R. |last=Hofmann |publisher=Blackwell |place=Oxford |year=1995 |isbn=978-0631178491}}
* {{Cite book| last = Duhem| first = Pierre Maurice Marie| others = Alan Aversa (trans.)| title = Ampère's Force Law: A Modern Introduction| access-date = 2019-07-03| date = 2018-09-09| url = https://isidore.co/calibre/get/PDF/6855| doi=10.13140/RG.2.2.31100.03206/1| doi-broken-date = 21 October 2025}} ([https://isidore.co/calibre/get/EPUB/6855 EPUB])

==External links==
{{Commons category}}
{{Wikiquote}}
{{wikisource|works=or}}
* [http://www.ampere.cnrs.fr Ampère and the history of electricity] – a French-language, edited by CNRS, site with Ampère's correspondence (full text and critical edition with links to manuscripts pictures, more than 1000 letters), an Ampère bibliography, experiments, and 3D simulations
* [https://web.archive.org/web/20080418102502/http://musee-ampere.univ-lyon1.fr/ Ampère Museum] – a French-language site from the museum in Poleymieux-au-Mont-d'or, near [[Lyon]], France
* [https://www.ifi.unicamp.br/~assis/Amperes-Electrodynamics.pdf ''Ampere's Electrodynamics''] Includes complete English translation of ''Theory of Electrodynamic Phenomena''
* [[:fr:Société des Amis d'André-Marie Ampère|"Société des Amis d'André-Marie Ampère"]], a French society dedicated to maintain the memory of André-Marie Ampère and in charge of the [[Ampère Museum]].
* {{MacTutor Biography|id=Ampere}}
* [http://www.newadvent.org/cathen/01437c.htm Catholic Encyclopedia on André Marie Ampère]

{{Scientists whose names are used as SI units}}
{{Authority control}}

{{DEFAULTSORT:Ampere, Andre-Marie}}
[[Category:1775 births]]
[[Category:1836 deaths]]
[[Category:Scientists from Lyon]]
[[Category:Electrostatics]]
[[Category:19th-century French physicists]]
[[Category:People associated with electricity]]
[[Category:Independent scientists]]
[[Category:French Roman Catholics]]
[[Category:Academic staff of the Collège de France]]
[[Category:Foreign members of the Royal Society]]
[[Category:Fellows of the Royal Society of Edinburgh]]
[[Category:Members of the French Academy of Sciences]]
[[Category:Members of the Royal Academy of Belgium]]
[[Category:Members of the Royal Swedish Academy of Sciences]]
[[Category:Honorary members of the Saint Petersburg Academy of Sciences]]
[[Category:Burials at Montmartre Cemetery]]
[[Category:Magneticians]]
[[Category:Academic staff of École Polytechnique]]