A Change of Meaning





To create a model of static Universe, Einstein introduced the cosmological term Lambda to counterbalance gravity's attraction on cosmic scales.
(2) 
G uv + Lamba * guv = 8 pi G * Tuv 


This term rho_vac, the energy density of the vacuum, multiplied by guv  must go on the right side of the field equation with the other forms of energy.
(3) 
G uv = 8 pi G ( Tuv + rho_vac*guv 


Although Einstein's cosmological term and the quantum vacuum energy are mathematical equivalent, conceptual they could not be more different: the former is a property of space, the latter a form of energy that arises from virtual particle antiparticle pairs.

That is a very clear description.

Quantum theory holds that these virtual particles constantly pop out of the vacuum, exist for a very brief time and then disappear.

Below this text is a sketch showing, what is involved.
What the physical implications are is not clear.
Box 1
