Five billion years ago, dark energy and matter density were constant

“On one level, the universe, with all of its dark baggage, seems to make sense. The total amount of matter and energy seems to be just enough to guarantee that the large-scale geometry of space-time is ‘flat,’ or Euclidean, a result that cosmologists have long considered to be the most desirable and aesthetic. On the other hand, the detailed breakdown of the constituents of the cosmos is ‘ugly’