Does macroscopic magnetic monopole contradict physics?

liumylife

I know Dirac had said yes to existence of microscopic monopole by quantum theory, so why not the macroscopic monopole?

vanhees71

Indeed, there's no principle against the existence of magnetic monopoles. In this sense it's a mystery, why there are no elementary magnetic charges in nature.

However, not long ago, one has found a funny material, which behaves like a socalled "spin ice". In this substance one has found collective excitations (quasiparticles) which behaves like magnetic monopoles. There are a lot of such examples in condensed matter physics!

liumylife

OK, since the quasipartical behaves like monopole, dose it produce magnetic field? Does moving "spin ice" produce EMR?