01
Dark-energy models are often characterized by an equation-of-state parameter w that relates pressure to energy density.
supportedDark-energy models are often characterized by an equation-of-state parameter w that relates pressure to energy density. Equation-of-state measurements test whether acceleration comes from Λ, dynamical fields, modified gravity, or other phenomena.
Learn this concept
Knowledge map
Evidence first
Dark-energy models are often characterized by an equation-of-state parameter w that relates pressure to energy density.
supportedIf dark-energy density evolves, its pressure and density change with the scale factor and alter distance-redshift relations and structure growth.
supportedCurrent data strongly constrain w near the cosmological-constant regime.
supported