Published online by Cambridge University Press: 20 November 2018
A subset $E$ of a discrete abelian group is called
$\varepsilon$-Kronecker if all
$E$-functions of modulus one can be approximated to within ϵ by characters.
$E$ is called a Sidon set if all bounded
$E$-functions can be interpolated by the Fourier transform of measures on the dual group. As
$\varepsilon$-Kronecker sets with
$\varepsilon \,<\,2$ possess the same arithmetic properties as Sidon sets, it is natural to ask if they are Sidon. We use the Pisier net characterization of Sidonicity to prove this is true.