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: Freefall
Famous quotes containing the words free, fall, general and/or relativity:
“‘Society’ in America means all the honest, kindly-mannered, pleasant- voiced women, and all the good, brave, unassuming men, between the Atlantic and the Pacific. Each of these has a free pass in every city and village, ‘good for this generation only,’ and it depends on each to make use of this pass or not as it may happen to suit his or her fancy.”
—Henry Brooks Adams (1838–1918)
“To slip upon a pavement is better than to slip with the tongue: so the fall of the wicked shall come speedily.”
—Apocrypha. Ecclesiasticus 20:18.
“The esteem of good men is the reward of our worth, but the reputation of the world in general is the gift of our fate.”
—François, Duc De La Rochefoucauld (1613–1680)
“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)