This gizmag article is succinct in its description of a new model of dark matter published by scientists at Lawrence Livermore National Laboratory (LLNL). The LLNL is a United States research facility primarily known for its projects involving nuclear weapons, national security, super-computing and high energy physics. This “stealth dark matter” model proposes that dark matter is currently invisible in our cold universe because it has condensed into giant electrically-neutral super-particles held together under an unknown fundamental force of interaction. But under the extremely high temperatures of the early universe dark matter existed essentially as a plasma, a plasma that interacted with “ordinary matter”. The scientists also propose using a high energy particle accelerator like the Large Hadron Collider (LHC) to recreate the conditions of the early universe and try to generate and detect the electrically charged dark matter particles that should be generated. Well, at least it keeps the high energy particle accelerators busy. It would be sad to see them sitting idle after so many billions of dollars were spent to build them. But to quote one of the chief scientists:
“It is remarkable that a dark matter candidate just several hundred times heavier than the proton could be a composite of electrically charged constituents and yet have evaded direct detection so far.”
Indeed, but I don’t think remarkable is quite the right word to use. Nevertheless, I do hold out hope. For if scientists can believe that dark matter plasma can interact with ordinary matter on a large scale perhaps one day they can believe that ordinary plasma can interact with it too.