Dark energy accounts for 70% of everything in the universe, and yet we know almost nothing about it. Now a new model meant to explain some impossibly massive galaxy clusters is here, to make dark energy even more fiendishly complex.
We're not here to dispute the existence of dark energy — for that discussion, check out Dr. Dave Goldberg's explanation of why dark energy really is essential. But still, dark energy remains a great unknown, something that while we understand what it does — cause the expansion of the universe to accelerate — we don't really have any idea how it does this, or even what it actually is. These are, admittedly, rather large questions to be answered.