Presented by Luca de Feo at the [[The Isogeny Club]]: (See recent paper, "Dlog is Practically as Hard (or Easy) as DH – Solving Dlogs via DH Oracles on EC Standards", May/Schneider, https://eprint.iacr.org/2023/539.pdf ) Let SCDH oracle: $h \longrightarrow h^z$ Compare to CDH oracle (which is stronger): $g, g^a, g^b \longrightarrow g^{ab}$ GAIP = Group Action Inverse Problem (?) If you can solve GAIP then you can solve CSIDH-CDH. In the other direction, if you can solve CSIDH-CDH, then you can solve GAIP *using a quantum computer*. ([[Shors algoritme]] is an essential part of the reduction.) ***