Edit 11-09-2016: Okay, the Universe may NOT be spinning. It's been a couple years since I've written this article and along with some great supportive models and theory, I have come across similar (but much more knowledgeable) discussion that shows this theory unlikely within the context of our current understanding of the universe's structure. As always though, I'm proud of my thoughts and misconceptions. They are drivers for my education and thus so, are left intact below.
Note: During my study, I also found that the idea of a collapsing universe was not necessary for gravitational acceleration towards a rotating circumference.
Dark energy may simply be centrifugal and centripetal forces inherent to a spinning universe.
Dark energy is an unknown force used to explain the accelerating expansion of our observable Universe. It is my humble opinion that this energy is created by the conservation of angular momentum of a collapsing universe.
This model assumes that the outer mass of the Universe has succumbed to centripetal forces and is collapsing back towards the center. And like the arms of the figure skater, the collapse reduces rotational inertia causing accelerated centrifugal force here within the area of the universe we can observe. Unlike the more rigid structure of the figure skater though, our more fluid inner portions of the inner universe allow expansion at an accelerated rate that is relative to the outer universe's collapse.
This theory seems to account for what appears to be an accelerated expansion rate from our limited view. I also like that it seems to be more in keeping with conventional physics. So to recap, the basic premise is that the expansion of the Universe is heterogeneous, the collapsing outer portions of our universe reduce rotational inertia, thus increasing total rotation speed and expansion of the inner Universe by centrifugal force.
But why would we think the Universe is rotating in the first place? Well the real question is, why would we not? For the Universe not to spin, all components of its expansion would have had to exert force exactly directional to an infinitely small point throughout its expansion. That point would have also had to have absolutely no previous rotation. Given those two unlikely conditions, I think it's safer to assume assume rotation exists than to assume it doesn't.
Back in May of 2011, Micheal Longo and his team published Detection of a dipole in the handedness of spiral galaxies with redshifts which asserts that the Universe has a preferred axis upon which it spins. His research showed an excess of left-handed spiral galaxies toward the north Galactic pole and an excess of right-handed in the opposite direction which suggests dissipation of angular momentum among the galaxies during expansion.
I'll be reading others' related research and looking for more information about conservation of angular motion in fluid environments. Let me know if there are sources I should check out.
Please pass this article on to interested parties. All comments and criticism is greatly appreciated.