First collisions at the LHC with unprecedented Energy! (Ask a particle physisicist)

[JuliaL]

Having the Dark matter in the form of a dark world as you propose, is a very exciting thought (I mean, how cool would that be), but unfortunately pretty firmly excluded by observations - we do after all know what the gravitational effects of the dark matter must look like, and your dark parallel world would not satisfy observations.

I am sad.
You, and this guy 'observations,' killed a fun idea.
I shall continue to pretend I own and care for a dark hamster.....named Ron.
It can't interact much less than my cat.

Whether it was the purpose of this thread or not.
Alex and Pyrrho, you have renewed my sense of wonder at how amazing the observed universe is and how much interesting speculation can be found in ostensibly simple questions when examined closely.