The Lagrangian in scalar-tensor theory can be expressed in the Jordan frame in which the scalar field or some function of it multiplies the Ricci scalar, or in the Einstein frame in which Ricci scalar is not multiplied by the scalar field. There exist various transformations between these frames. Despite the fact that these frames have been around for some time there is currently heated debate about whether either, both, or neither frame is a 'physical' frame which can be compared to observations and experiment.
If we perform the Weyl rescaling, then the Riemann and Ricci tensors are modified.
Famous quotes containing the words string, frame and/or einstein:
“Supposing everyone lived at one time what would they say. They would observe that stringing string beans is universal.”
—Gertrude Stein (1874–1946)
“Painting seems to be to the eye what dancing is to the limbs. When that has educated the frame to self-possession, to nimbleness, to grace, the steps of the dancing-master are better forgotten; so painting teaches me the splendor of color and the expression of form, and as I see many pictures and higher genius in the art, I see the boundless opulence of the pencil, the indifferency in which the artist stands free to choose out of the possible forms.”
—Ralph Waldo Emerson (1803–1882)
“When you are courting a nice girl an hour seems like a second. When you sit on a red-hot cinder a second seems like an hour. That’s relativity.”
—Albert Einstein (1879–1955)