Bertrand’s and Rodriguez Villegas’ conjecture for real multi-quadratic Galois extensions of the rationals
Journal de théorie des nombres de Bordeaux, Tome 38 (2026) no. 1, pp. 57-69

The conjecture due to Bertrand and Rodriguez Villegas asserts that the 1-norm of the nonzero element in an exterior power of the units of a number field has a certain lower bound. We prove this conjecture for the exterior square case when the number field is a real multi-quadratic Galois extension of any degree of the rationals.

La conjecture due à Bertrand et Rodriguez Villegas affirme que la norme 1 d’un élément non nul dans une puissance extérieure des unités d’un corps de nombres admet une certaine borne inférieure. Nous démontrons cette conjecture dans le cas du carré extérieur lorsque le corps de nombres est une extension galoisienne multiquadratique réelle, de degré quelconque, du corps des rationnels.

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DOI : 10.5802/jtnb.1354
Classification : 11R27, 11G50
Keywords: Bertrand–Rodriguez Villegas conjecture, units
Licence : CC-BY-ND 4.0
Droits d'auteur : Les auteurs conservent leurs droits
Dohyeong Kim; Seungho Song. Bertrand’s and Rodriguez Villegas’ conjecture for real multi-quadratic Galois extensions of the rationals. Journal de théorie des nombres de Bordeaux, Tome 38 (2026) no. 1, pp. 57-69. doi: 10.5802/jtnb.1354
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     journal = {Journal de th\'eorie des nombres de Bordeaux},
     pages = {57--69},
     year = {2026},
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