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arXiv · 1506.02696

Simultaneous $p$-orderings and minimising volumes in number fields

Jakub Byszewski·Mikołaj Frączyk·Anna Szumowicz
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Abstract

In the paper "On the interpolation of integer-valued polynomials" (Journal of Number Theory 133 (2013), pp. 4224--4232.) V. Volkov and F. Petrov consider the problem of existence of the so-called $n$-universal sets (related to simultaneous $p$-orderings of Bhargava) in the ring of Gaussian integers. We extend their results to arbitrary imaginary quadratic number fields and prove an existence theorem that provides a strong counterexample to a conjecture of Volkov-Petrov on minimal cardinality of $n$-universal sets. Along the way, we discover a link with Euler-Kronecker constants and prove a lower bound on Euler-Kronecker constants which is of the same order of magnitude as the one obtained by Ihara.

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Jakub Byszewski, Mikołaj Frączyk, Anna Szumowicz. 2016-11-23. Simultaneous $p$-orderings and minimising volumes in number fields. https://doi.org/10.1016/j.jnt.2016.09.010

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