The Mahler measure of exact polynomials in three variables
Thu Ha Trieu
TL;DR
The paper shows that, under explicit Beilinson conjecture inputs for genus 1 curves, the Mahler measure of a three-variable polynomial P can be expressed in terms of elliptic-curve L-values $L'(E,-1)$ and Bloch-Wigner dilogarithm values, with Dirichlet L-values arising in special cases. The method builds a Deligne cohomology class from the Maillot genus-1 curve via Goncharov and De Jeu polylogarithmic complexes and their regulator maps, then constructs a motivic cohomology class whose Beilinson regulator matches the Deligne class; Beilinson’s conjecture then yields the stated regulator–L-value formulas. The framework is used to derive numerous conjectural Mahler-measure identities (pure and mixed) attributed to Boyd and Brunault, and includes unconditional Dirichlet-based results via Lalín’s approach. Overall, the work links Mahler measures to explicit regulator computations on genus-1 curves, advancing a regulator-based, Beilinson-guided understanding of three-variable Mahler identities and their arithmetic content.
Abstract
We prove that under certain explicit conditions, the Mahler measure of a three-variable polynomial can be expressed in terms of elliptic curve $L$-values and Bloch-Wigner dilogarithmmic values, conditionally on Beilinson's conjecture. In some cases, these dilogarithmic values simplify to Dirichlet $L$-values. The proof involves a construction of an element in $K_4^{(3)}$ of a smooth projective curve over a number field. This generalizes a result of Lalín for the polynomial $z + (x+1)(y+1)$. We apply our method to several other Mahler measure identities conjectured by Boyd and Brunault.
