Septic equation

Septic equation

Clean up duplicate template arguments using findargdups

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The general septic equation can be solved with the [[alternating group|alternating]] or [[symmetric group|symmetric]] [[Galois group]]s {{math|''A''7}} or {{math|''S''7}}.{{Cite book |last=King |first=R. Bruce |date=2009 |title=Beyond the Quartic Equation |url= https://books.google.com/books?id=9cKX_9zkeg4C&q=septic+equation&pg=PA143 |location=Boston/Basel/Berlin |publisher=Birkhäuser |page=143, 144 |isbn=978-0-8176-4849-7}} Such equations require [[hyperelliptic function]]s and associated [[theta function]]s of [[genus (mathematics)|genus]] 3 for their solution. However, these equations were not studied specifically by the nineteenth-century mathematicians studying the solutions of algebraic equations, because the [[sextic equation]]s' solutions were already at the limits of their computational abilities without computers.
The general septic equation can be solved with the [[alternating group|alternating]] or [[symmetric group|symmetric]] [[Galois group]]s {{math|''A''7}} or {{math|''S''7}}.{{Cite book |last=King |first=R. Bruce |date=2009 |title=Beyond the Quartic Equation |url= https://books.google.com/books?id=9cKX_9zkeg4C&q=septic+equation&pg=PA143 |location=Boston/Basel/Berlin |publisher=Birkhäuser |page=143, 144 |isbn=978-0-8176-4849-7}} Such equations require [[hyperelliptic function]]s and associated [[theta function]]s of [[genus (mathematics)|genus]] 3 for their solution. However, these equations were not studied specifically by the nineteenth-century mathematicians studying the solutions of algebraic equations, because the [[sextic equation]]s' solutions were already at the limits of their computational abilities without computers.


Septics are the lowest order equations for which it is not obvious that their solutions may be obtained by composing ''continuous functions'' of two variables. [[Hilbert's thirteenth problem|Hilbert's 13th problem]] was the conjecture this was not possible in the general case for seventh-degree equations. [[Vladimir Arnold]] solved this in 1957, demonstrating that this was always possible.{{Cite book |last=King |first=Vasco |last=Brattka |date=2007 |chapter=From Hilbert’s 13th Problem to the theory of neural networks: constructive aspects of Kolmogorov’s Superposition Theorem |chapter-url=https://books.google.com/books?id=SpTv44Ia-J0C&pg=PA254 |title=Kolmogorov's Heritage in Mathematics |location=Berlin/Heidelberg |publisher=Springer |page=253–280 |isbn=978-3-540-36349-1}} However, Arnold himself considered the ''genuine'' Hilbert problem to be whether for septics their solutions may be obtained by superimposing ''algebraic functions'' of two variables.{{citation |url=http://www.pdmi.ras.ru/~arnsem/Arnold/arnlect1.ps.gz |title=From Hilbert's Superposition Problem to Dynamical Systems |author=V.I. Arnold |page=4}} As of 2023, the problem is still open.
Septics are the lowest order equations for which it is not obvious that their solutions may be obtained by composing ''continuous functions'' of two variables. [[Hilbert's thirteenth problem|Hilbert's 13th problem]] was the conjecture this was not possible in the general case for seventh-degree equations. [[Vladimir Arnold]] solved this in 1957, demonstrating that this was always possible.{{Cite book |first=Vasco |last=Brattka |date=2007 |chapter=From Hilbert’s 13th Problem to the theory of neural networks: constructive aspects of Kolmogorov’s Superposition Theorem |chapter-url=https://books.google.com/books?id=SpTv44Ia-J0C&pg=PA254 |title=Kolmogorov's Heritage in Mathematics |location=Berlin/Heidelberg |publisher=Springer |page=253–280 |isbn=978-3-540-36349-1}} However, Arnold himself considered the ''genuine'' Hilbert problem to be whether for septics their solutions may be obtained by superimposing ''algebraic functions'' of two variables.{{citation |url=http://www.pdmi.ras.ru/~arnsem/Arnold/arnlect1.ps.gz |title=From Hilbert's Superposition Problem to Dynamical Systems |author=V.I. Arnold |page=4}} As of 2023, the problem is still open.


==Galois groups==
==Galois groups==