The universe consists of particles and fields, which can be mapped to vertexes and edges on a graph. The graph isn't fully connected. It isn't close. It should

The universe consists of particles and fields, which can be mapped to vertexes and edges on a graph. The graph isn't fully connected. It isn't close. It shouldn't be a surprise that some particles are only connected to each other via gravity -- several are only connected via two. What I find interesting is the possibility that dark matter is made up of multiple particles, which interact with each other, but not ours. There might be multiple such groupings. That would neatly explain why most of the universe is dark matter, and we ourselves would be dark matter to someone else.