You can apply Noether's 2nd theorem to Friedmann cosmology with cosmological time as your generator. This yields the expected contributions to the energy densit

You can apply Noether's 2nd theorem to Friedmann cosmology with cosmological time as your generator. This yields the expected contributions to the energy density, with an additional negative term that is (if I remember correctly) proportional to H² and gets interpreted as energy of the gravitational field by some.