The Action
The action of the Einstein æther theory is generally taken to consist of the sum of the Einstein–Hilbert action with a Lagrange multiplier λ that ensures that the time vector is a unit vector and also with all of the covariant terms involving the time vector u but having at most two derivatives.
In particular it is assumed that the action may be written as the integral of a local Lagrangian density
where GN is Newton's constant and g is a metric with Minkowski signature. The Lagrangian density is
Here R is the Ricci scalar, is the covariant derivative and the tensor K is defined by
Here the ci are dimensionless adjustable parameters of the theory.
Read more about this topic: Einstein Aether Theory
Famous quotes containing the word action:
“In 1845 he built himself a small framed house on the shores of Walden Pond, and lived there two years alone, a life of labor and study. This action was quite native and fit for him. No one who knew him would tax him with affectation. He was more unlike his neighbors in his thought than in his action. As soon as he had exhausted himself that advantages of his solitude, he abandoned it.”
—Ralph Waldo Emerson (18031882)
“Suit the action to the word, the word to the action, with this special observance, that you oerstep not the modesty of nature.”
—William Shakespeare (15641616)
