reason to neglect the dipole-dipole interaction in any system where the DM interaction is known to be important. This calls for a re-evaluation of a number of interesting problems, some of which we list in the following subsection.

Significance of the dipole-dipole interaction {#subsec:IV.B}
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We conclude by discussing a number of problems where the dipole-dipole interaction is either known to be important, or might be important, with an emphasis on low-temperature magnets and other fermion systems.

\(1) Classical Heisenberg ferromagnets. This problem was worked on in great detail by Aharony and Fisher[@Aharony_Fisher_1973] for the static critical behavior and by Frey and Schwabl[@Frey_Schwabl_1994] for the dynamical critical behavior. The renormalization group done by Aharony and Fisher started from a nonlocal order parameter theory, Eqs. (\[eqs:2.7\]), which leads to a somewhat nonconventional renormalization procedure. The nonlocality in Eqs.(\[eqs:2.7\]) is due to integrating out the gauge field fluctuations or photons. It would be interesting to repeat this calculation starting from the coupled local field theory given by our Eqs. (\[eqs:2.2\]) before these fluctuations are integrated out.

\(2) Classical helimagnets. The standard phase transition treatment for helimagnetism due to the DM interaction is due to Bak and Jensen.[@Bak_Jensen_1980] Neglecting the dipole-dipole interaction term 