English

Explicit mock Heegner points and BSD formula on certain Mordell curves

Number Theory 2026-07-29 v1

Abstract

For a natural number aa, let E2aE_{2a} be the Mordell elliptic curve X3+Y3=2aX^3 +Y^3=2a. We give an explicit construction of (mock) Heegner point on the Mordell curve E2pE_{2p} for a prime p4mod9p\equiv 4 \mod 9 and E2p2E_{2p^2} for a prime p7mod9p\equiv 7 \mod 9, under the assumption that 22 is not a cube modulo pp. We also verify the explicit Gross-Zagier formula for these curves and go on to show that the BSD formula holds for these curves up to a 22-adic unit. Using a result of Burungale-Flach, we show that the full BSD formula holds for the rank zero curve E2pE_{2p} for p7mod9p\equiv 7 \mod 9 and E2p2E_{2p^2} for p4mod9p\equiv 4 \mod 9, whenever 22 is not a cube modulo pp.

Cite

@article{arxiv.2607.26774,
  title  = {Explicit mock Heegner points and BSD formula on certain Mordell curves},
  author = {Sumita Gunri and Somnath Jha and Dipramit Majumdar},
  journal= {arXiv preprint arXiv:2607.26774},
  year   = {2026}
}