Maximal Theta Functions -- Universal Optimality of the Hexagonal Lattice for Madelung-Like Lattice Energies

Understand

We present two families of lattice theta functions accompanying the family of lattice theta functions studied by Montgomery in [H.~Montgomery.

• Minimal theta functions.
• \textit{Glasgow Mathematical Journal}, 30(1):75--85, 1988].
• The studied theta functions are generalizations of the Jacobi theta-2 and theta-4 functions.