TASI lectures on the cosmological constant

  title={TASI lectures on the cosmological constant},
  author={Raphael Bousso},
The energy density of the vacuum, Λ, is at least 60 orders of magnitude smaller than several known contributions to it. Approaches to this problem are tightly constrained by data ranging from elementary observations to precision experiments. Absent overwhelming evidence to the contrary, dark energy can only be interpreted as vacuum energy, so the venerable assumption that Λ = 0 conflicts with observation. The possibility remains that Λ is fundamentally variable, though constant over large… CONTINUE READING