Results 1 to 10 of about 10,757 (241)
The modular automorphisms of quotient modular curves
Mathematika, Volume 72, Issue 1, January 2026.Abstract We obtain the modular automorphism group of any quotient modular curve of level N$N$, with 4,9∤N$4,9\nmid N$. In particular, we obtain some unexpected automorphisms of order 3 that appear for the quotient modular curves when the Atkin–Lehner involution w25$w_{25}$ belongs to the quotient modular group. We also prove that such automorphisms are
Francesc Bars, Tarun Dalal
wiley +1 more source
The arithmetic of genus two curves with (4,4)-split Jacobians
, 2011 In this paper we study genus 2 curves whose Jacobians admit a polarized (4,4)-isogeny to a product of elliptic curves. We consider base fields of characteristic different from 2 and 3, which we do not assume to be algebraically closed.
Bolza +21 more
core +1 more source
A note on the cohomology of moduli spaces of local shtukas
Bulletin of the London Mathematical Society, Volume 57, Issue 12, Page 3709-3729, December 2025.Abstract We study localized versions of spectral action of Fargues–Scholze, using methods from higher algebra. As our main motivation and application, we deduce a formula for the cohomology of moduli spaces of local shtukas under certain genericity assumptions, and discuss its relation with the Kottwitz conjecture.
David Hansen, Christian Johansson
wiley +1 more source
Pairing Optimizations for Isogeny-Based Cryptosystems
IET Information SecurityIn isogeny-based cryptography, bilinear pairings are regarded as a powerful tool in various applications, including key compression, public key validation, and torsion basis generation. However, in most isogeny-based protocols, the performance of pairing
Shiping Cai, Kaizhan Lin, Chang-An Zhao
doaj +1 more source
Efficient Commutative PQC Algorithms on Isogenies of Edwards Curves
CryptographyThe article presents the author’s works in the field of modifications and modeling of the Post-Quantum Cryptography (PQC) Commutative Supersingular Isogeny Diffie-Hellman (CSIDH) algorithm on non-cyclic supersingular Edwards curves and its predecessor ...
Anatoly Bessalov +2 more
doaj +1 more source
The geometry and arithmetic of bielliptic Picard curves
Journal of the London Mathematical Society, Volume 112, Issue 5, November 2025.Abstract We study the geometry and arithmetic of the curves C:y3=x4+ax2+b$C \colon y^3 = x^4 + ax^2 + b$ and their associated Prym abelian surfaces P$P$. We prove a Torelli‐type theorem in this context and give a geometric proof of the fact that P$P$ has quaternionic multiplication by the quaternion order of discriminant 6.
Jef Laga, Ari Shnidman
wiley +1 more source
The $3$-isogeny Selmer groups of the elliptic curves $y^2=x^3+n^2$ [PDF]
, 2022 Stephanie Chan
openalex +1 more source
Efficiency of SIDH-based signatures (yes, SIDH)
Journal of Mathematical CryptologyIn this note, we assess the efficiency of a supersingular isogeny Diffie-Hellman (SIDH)-based digital signature built on a weaker variant of a recent identification protocol proposed by Basso et al.
Ghantous Wissam +2 more
doaj +1 more source
Weakly special threefolds and nondensity of rational points
Journal of the London Mathematical Society, Volume 112, Issue 5, November 2025.Abstract We verify part of a conjecture of Campana predicting that rational points on the weakly special nonspecial simply connected smooth projective threefolds constructed by Bogomolov–Tschinkel are not dense. To prove our result, we establish fundamental properties of moduli spaces of orbifold maps, and prove a dimension bound for such moduli spaces
Finn Bartsch +2 more
wiley +1 more source
A trade-off between classical and quantum circuit size for an attack against CSIDH
Journal of Mathematical Cryptology, 2020 We propose a heuristic algorithm to solve the underlying hard problem of the CSIDH cryptosystem (and other isogeny-based cryptosystems using elliptic curves with endomorphism ring isomorphic to an imaginary quadratic order 𝒪).
Biasse Jean-François +4 more
doaj +1 more source