Free Fall in General Relativity
In GR, an object in free fall is subject to no force and is an inertial body moving along a geodesic. Far away from any sources of space time curvature, where spacetime is flat, Newtonian theory of free fall agrees with GR but otherwise the two disagree. The experimental observation that all objects in free fall accelerate at the same rate, as noted by Galileo and then ambodied in Newton's theory as the equality of gravitational and inertial masses, and later confirmed to high accuracy by modern forms of the Eötvös experiment, is the basis of the Equivalence Principle, from which basis Einstein's theory of general relativity initially took off.
Read more about this topic: Free Fall
Famous quotes containing the words free, fall, general and/or relativity:
“For good and evil, man is a free creative spirit. This produces the very queer world we live in, a world in continuous creation and therefore continuous change and insecurity.”
—Joyce Cary (1888–1957)
“Strictly speaking, one cannot legislate love, but what one can do is legislate fairness and justice. If legislation does not prohibit our living side by side, sooner or later your child will fall on the pavement and I’ll be the one to pick her up. Or one of my children will not be able to get into the house and you’ll have to say, “Stop here until your mom comes here.” Legislation affords us the chance to see if we might love each other.”
—Maya Angelou (b. 1928)
“Suppose we think while we talk or write—I mean, as we normally do—we shall not in general say that we think quicker than we talk, but the thought seems not to be separate from the expression.”
—Ludwig Wittgenstein (1889–1951)
“By an application of the theory of relativity to the taste of readers, to-day in Germany I am called a German man of science, and in England I am represented as a Swiss Jew. If I come to be regarded as a bête noire the descriptions will be reversed, and I shall become a Swiss Jew for the Germans and a German man of science for the English!”
—Albert Einstein (1879–1955)