Moon–Taguchi bounded-conductor finiteness conjecture

For every global function field KK of characteristic pp, every integer n≥1n\ge 1, and every effective divisor DD on KK, there are only finitely many isomorphism classes of continuous, semisimple, geometric representations ρ:GK→GLn(F‾p)\rho:G_K\to\mathrm{GL}_n(\overline{\mathbf F}_p) whose conductor satisfies f(ρ)≤D\mathfrak f(\rho)\le D.

References

Primary source

arXiv

Additional references

Progress summary

Refreshed
Claimed solved

A 2026 paper claims the conjecture fails without a lifting assumption in equal characteristic, while settling the two-dimensional case.

Khare and Moon proposed the number-field conjecture; Moon and Taguchi formulated its function-field analogue. It asks for finiteness of geometric representations with conductor bounded by a fixed divisor.

Known results

  • Moon and Taguchi: solvable-image representations.
  • Böckle and Khare: large image, p∤np\nmid n, and everywhere tame ramification.
  • Further cases with p∤np\nmid n were implicit in earlier work.
  • A 2026 paper claims the conjecture when pp is odd or n=2n=2.

September 2026 equal-characteristic refutation

On September 10, 2026, Luo and Xu reported that bounded-conductor finiteness fails in equal characteristic without lifting, while identifying a positive lifting regime. Combined with cross-characteristic results, this gives a claimed complete resolution in dimension 22 across characteristics; higher dimensions remain unresolved in the unrestricted characteristic-22 case.

Current status (as of September 2026): The two-dimensional case is claimed settled, but the equal-characteristic refutation and the stated higher-dimensional boundaries remain unverified.

Sources

Solutions 0

No solutions have been posted yet.