I make no claim to even begin to understand astrophysics, or in fact any sort of physics at all, but sometimes when I read an article written for the popular audience, explaining some newly discovered phenomena or discussing a new theory about some aspect of the physical universe that I had never heard of or even imagined, I am stopped dead with amazement, and an enormous vista of infinite possibilities appears before my mind's eye.
So apparently, there may be an unknown force causing objects in the universe to move in away that cannot be explained by anything within the known universe.
http://www.space.com/scienceastronomy/080923-dark-flows.html
Also, apparently a theory related to the Big Bang theory, called inflation, speculates that there may be regions of the universe, or cosmos, inaccessible to our observation, that do not contain stars and galaxies, which might indeed only be products of local mass density patterns.
Because of the limits on our ability to observe the universe any ideas about the universe outside our inflation bubble are pure imagination, or poetry.
"In these regions, space-time might be very different, and likely doesn't contain stars and galaxies (which only formed because of the particular density pattern of mass in our bubble). It could include giant, massive structures much larger than anything in our own observable universe. These structures are what researchers suspect are tugging on the galaxy clusters, causing the dark flow." Clara Moskowitz, Space.com
I feel, in fact, like Keats's Cortez.