Editing André-Marie Ampère (section)

===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}}