I like Erik Verlinde's theory and papers. Definitely worth a read. Some of his thinking is consistent with the "mirror matter" proposition, so long as the mystery particles are generally located in a parallel dimension, so that they interact with normal matter minimally no matter how they are characterized... and which dimension has remarkable similarity to Dirac's reciprocal space. To claim that something (mysterious) is an emergent property of something else (better known) is framing the problem philosophically and of limited value in pointing to a real-world application unless the particles are literally emerging from one dimension into another dimension - aka: mirror matter oscillation.
Admittedly, most of this is well above my pay grade to comprehend - so unless there is a particularly useful aspect of any theory which can be incorporated into LENR experiment, it is more like flag-waving. When a researcher says he has evidence that 1% of any neutron beam oscillates so as to exhibit the properties of a different kind of neutron ... and can decay in our 3-space even if came from another space - that sounds like a detail which can be useful somehow and incorporated into experiment. The more one looks at the Bush/Eagleton rubidium experiment, the more it seems to do this (despite the inventors being completely wrong on their own explanation), In LENR it seems there is a high probability that hydrogen morphs into "something else" when confined in a metal matrix - and which species may not be the result of nuclear fusion per se. Having a better understanding of the properties of that particle would be important - especially if it has some broader relevance to a Universal phenomena like dark matter. From: CB Sites Every story on dark matter simply leaves me confused and perplexed. The first question I would ask is what is the spin of dark matter. Is it a fermion or boson? If it's a fermion, it has to interact and if it interacts why is it nearly impossible to see the interaction. If it's a Boson, then it would tend to undergo condensation, and you would have a bose star or a dark matter black hole. That too should be easy to observe as a gravitational lens without a source of matter to create it. Both have led me to conclude that dark matter is part of the concept of Emergent Gravity (Entropic Gravity). Emergent gravity (and emergent dark matter) doesn't have spin but would effect matter gravitationally and be associated with matter since it appears out of the warping of small amounts space/time by the occupation of matter and the entropic warping of space-time from matter. This is all from Erik Verlinde's theory. It's good stuff and I don't understand why it's not the leading candidate for a dark matter explanation.