Fricke involution
From HandWiki
In mathematics, a Fricke involution is the involution of the modular curve X0(N) given by τ → –1/Nτ. It is named after Robert Fricke. The Fricke involution also acts on other objects associated with the modular curve, such as spaces of modular forms and the Jacobian J0(N) of the modular curve.
See also
- Atkin–Lehner involution
References
- Iwaniec, Henryk (1997), Topics in classical automorphic forms, Graduate Studies in Mathematics, 17, Providence, R.I.: American Mathematical Society, ISBN 978-0-8218-0777-4, https://books.google.com/books?id=Crds_5HZl2QC
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