I came across this article about a new theory regarding the nature of dark matter. I recommend giving it a read, in part because I think it is good for all of us non-physics types to appreciate how much of the ‘basic’ cosmology we were taught as fact is still under debate. Even things that many of us comfortably treat as real (like black holes) might be artifacts of a mathematical model and the phenomena they explain might be better explained by another model; we just haven’t got all the data in to settle the issues.
I have mentioned this before, but one of the things I appreciate about George Yeats is her understanding of the medium’s role in mediumship. She makes clear that the quality of the medium shapes the quality of the message. The medium has to work at being a good medium and that includes developing their intellectual faculties so that spirits have easier access to concepts for communicating.