On the other hand , we know pretty well where our current theories break down quantum gravity should become apparent near the planck scale , and then there ' s anomalies such as dark matter dark energy . A microwave cavity is not approaching the planck scale , and if EM interacted with dark matter it wouldn ' t be dark . Otherwise difficult to see how this would tie in with dark energy which is a truly minuscule energy density . If this were a real effect , it would necessarily have to be an outofleftfield kind of thing , not related to our current understanding of how our theories are incomplete and therefore not motivated by the fact that we know our theories are incomplete , except in a very abstract sense .