3 papers
math-ph2022
Onset of pattern formation in thin ferromagnetic films with perpendicular anisotropy
Birger Brietzke, Hans Knüpfer
We consider the onset of pattern formation in an ultrathin ferromagnetic film of the form for with preferred p…
math-ph2019
The Second Order Correction to the Ground State Energy of the Dilute Bose Gas
Birger Brietzke, Jan Philip Solovej
We establish the Lee-Huang-Yang formula for the ground state energy of a dilute Bose gas for a broad class of repulsive pair-interactions in 3D as a lower bound. Our result is vali…
math-ph2019
A simple 2nd order lower bound to the energy of dilute Bose gases
Birger Brietzke, Søren Fournais, Jan Philip Solovej
For a dilute system of non-relativistic bosons interacting through a positive, radial potential with scattering length we prove that the ground state energy density satisfi…