- Source: Elliptic gamma function
In mathematics, the elliptic gamma function is a generalization of the q-gamma function, which is itself the q-analog of the ordinary gamma function. It is closely related to a function studied by Jackson (1905), and can be expressed in terms of the triple gamma function. It is given by
Γ
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=
∏
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∞
∏
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∞
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{\displaystyle \Gamma (z;p,q)=\prod _{m=0}^{\infty }\prod _{n=0}^{\infty }{\frac {1-p^{m+1}q^{n+1}/z}{1-p^{m}q^{n}z}}.}
It obeys several identities:
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{\displaystyle \Gamma (z;p,q)={\frac {1}{\Gamma (pq/z;p,q)}}\,}
Γ
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θ
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Γ
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{\displaystyle \Gamma (pz;p,q)=\theta (z;q)\Gamma (z;p,q)\,}
and
Γ
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q
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p
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=
θ
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Γ
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{\displaystyle \Gamma (qz;p,q)=\theta (z;p)\Gamma (z;p,q)\,}
where θ is the q-theta function.
When
p
=
0
{\displaystyle p=0}
, it essentially reduces to the infinite q-Pochhammer symbol:
Γ
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{\displaystyle \Gamma (z;0,q)={\frac {1}{(z;q)_{\infty }}}.}
Multiplication Formula
Define
Γ
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:=
(
q
;
q
)
∞
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p
;
p
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∞
(
θ
(
q
;
p
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1
−
z
∏
m
=
0
∞
∏
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=
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∞
1
−
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+
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+
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{\displaystyle {\tilde {\Gamma }}(z;p,q):={\frac {(q;q)_{\infty }}{(p;p)_{\infty }}}(\theta (q;p))^{1-z}\prod _{m=0}^{\infty }\prod _{n=0}^{\infty }{\frac {1-p^{m+1}q^{n+1-z}}{1-p^{m}q^{n+z}}}.}
Then the following formula holds with
r
=
q
n
{\displaystyle r=q^{n}}
(Felder & Varchenko (2002)).
Γ
~
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Γ
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Γ
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⋯
Γ
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(
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/
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=
(
θ
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θ
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n
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Γ
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⋯
Γ
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{\displaystyle {\tilde {\Gamma }}(nz;p,q){\tilde {\Gamma }}(1/n;p,r){\tilde {\Gamma }}(2/n;p,r)\cdots {\tilde {\Gamma }}((n-1)/n;p,r)=\left({\frac {\theta (r;p)}{\theta (q;p)}}\right)^{nz-1}{\tilde {\Gamma }}(z;p,r){\tilde {\Gamma }}(z+1/n;p,r)\cdots {\tilde {\Gamma }}(z+(n-1)/n;p,r).}
References
Felder, G.; Varchenko, A. (2002). "Multiplication Formulas for the Elliptic Gamma Function". arXiv:math/0212155.
Jackson, F. H. (1905), "The Basic Gamma-Function and the Elliptic Functions", Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character, 76 (508), The Royal Society: 127–144, Bibcode:1905RSPSA..76..127J, doi:10.1098/rspa.1905.0011, ISSN 0950-1207, JSTOR 92601
Gasper, George; Rahman, Mizan (2004), Basic hypergeometric series, Encyclopedia of Mathematics and its Applications, vol. 96 (2nd ed.), Cambridge University Press, ISBN 978-0-521-83357-8, MR 2128719
Ruijsenaars, S. N. M. (1997), "First order analytic difference equations and integrable quantum systems", Journal of Mathematical Physics, 38 (2): 1069–1146, Bibcode:1997JMP....38.1069R, doi:10.1063/1.531809, ISSN 0022-2488, MR 1434226
Felder, Giovanni; Henriques, André; Rossi, Carlo A.; Zhu, Chenchang (2008). "A gerbe for the elliptic gamma function". Duke Mathematical Journal. 141. arXiv:math/0601337. doi:10.1215/S0012-7094-08-14111-0. S2CID 817920.
Kata Kunci Pencarian:
- Fungsi theta
- Sinus dan kosinus
- Hipotesis Riemann
- Daftar masalah matematika yang belum terpecahkan
- Elliptic gamma function
- Gamma function
- Jacobi elliptic functions
- Elliptic function
- Multiple gamma function
- Modular form
- Particular values of the gamma function
- List of mathematical functions
- Theta function
- Elliptic integral
