Extended theories of gravity Extended theories of gravity Extended theories of gravity are alternative theories of gravity developed from the exact starting points investigated first by Einstein and Hilbert. These are theories describing gravity, which are metric theory, "a linear connection" or related affine theories, or metric-affine gravitation theory. Rather than trying to discover correct calculations for the matter side of the Einstein field equations; which include inflation, dark energy, dark matter, large-scale structure, and possibly quantum gravity; it is proposed, instead, to change the gravitational side of the equation. One such theory is also an extension to general relativity and Newton's Universal gravity
Three Laws of Robotics the editor of "Astounding Science-Fiction". Campbell rejected it, claiming that it bore too strong a resemblance to Lester del Rey's "Helen O'Loy", published in December 1938; the story of a robot that is so much like a person that she falls in love with her creator and becomes his ideal wife. Frederik Pohl published "Robbie" in "Astonishing Stories" magazine the following year. Asimov attributes the Three Laws to John W. Campbell, from a conversation that took place on 23 December 1940. Campbell claimed that Asimov had the Three Laws already in his mind and that they simply needed to be