$$ \newcommand\F{\mathbb F} \newcommand\P{\mathbb P} \newcommand\A{\mathbb A} \newcommand\T{\mathbb T} \newcommand\msO{\mathscr O} \newcommand\msL{\mathscr L} \newcommand\ms{\mathscr} \newcommand\GL{\opname{GL}} \newcommand\eps{\varepsilon} \newcommand\opname{\operatorname} \newcommand\Proj{\opname{Proj}} \newcommand\Pic{\opname{Pic}} \newcommand\hom{\opname H} \newcommand\Char{\opname{char}} \newcommand\Hom{\opname{Hom}} \newcommand\Sel{\opname{Sel}} \newcommand\inv[2][1]{#2^{-#1}} \newcommand\pinv[2][1]{\inv[#1]{\p{#2}}} \newcommand\p[1]{\left(#1\right)} $$

Niven T. Achenjang


I am a math grad student at MIT, broadly interested in arithmetic geometry and especially in points on varieties. My advisor is Bjorn Poonen.

You can find my cv here, once I make an up to date one.

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Oct 12, 2023 I posted a new paper on arxiv. It is about bounding the average size of \(2\)-Selmer groups of elliptic curves \(E\) over characteristic \(2\) function fields. It also produces some new bounds on \(\dim_{\F_2}\Sel_2(E/K)\) when \(\Char K=2\) (and \(K\) is a global function field).
Aug 2023 I’m gonna try running a seminar on modularity and Fermat.
Jul 12, 2023 My paper with Jackson Morrow, in which we construct new examples of irreducible divisors on varieties whose complements can only have finitely many integral points, was published.
Jul 2023 I attended the AGNES Summer School on Intersection Theory on Moduli Spaces.
Jun 2023 I attended an MRC on Explicit Computations with Stacks.


  1. ArXiv
    The Average Size of 2-Selmer Groups of Elliptic Curves in Characteristic 2
    Achenjang, Niven
  2. IMRN
    Integral Points on Varieties With Infinite Étale Fundamental Group
    Achenjang, Niven T, and Morrow, Jackson S
    International Mathematics Research Notices,  2023
  3. IJNT
    On gaps in the closures of images of divisor functions
    Achenjang, Niven, and Berger, Aaron
    International Journal of Number Theory,  2019