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abstraction > hypothesis > theory > law > gravity law

gravity law
subject			fact

gravity law	has domain gravity
	is a kind of law
law	has discoverer
theory	has validity correct or incorrect with caveats
	has author or reasearch group
	has date or a range of dates for which the theory was active

Kinds of gravity law :

• equivalence principle (6 facts) - States that inertial mass is indistinguishable from gravitational mass., Core principle of general relativity declaring the indistinguishability of accelerated motion and immersion in a gravitational field (over small enough regions of observation). Generalizes the principle of relativity by showing that all observers, regardless of their state of motion, can claim to be at rest, so long as they acknowledge the presence of a suitable gravitational field., In a freely falling and nonrotating laboratory the laws of physics, including their numerical content, are the same everywhere including gravity-free space., The principle that it is impossible to distinguish between gravitational and inertial forces; gravitational mass is precisely equal to inertial mass., The statement that a gravitational force is completely equivalent in all of its physical effects to an overall acceleration in the opposite direction. For example, a person in an elevator in space accelerating upward at 32 feet per second per second would feel the floor pushing upward against her feet in exactly the same way as if the elevator were at rest on earth, where gravity pulls downward with an acceleration of 32 feet per second per second. The "weak equivalence principle," which is not as strong as the equivalence principle, states that all objects, independent of their mass or composition, fall with the same acceleration in the presence of gravity. The Eötvös experiment, and later refinements of this experiment, have proven the weak equivalence principle.
• Kepler's Law (3 kinds, 12 facts) - One of three orbital laws formulated by Kepler
• Newton's theory of gravity (6 facts) (inverse square law) - Theory of gravity declaring that the force of attraction between two bodies is proportional to the product of their masses and inversely proportional to the square of the distance between them. Subsequently supplanted by Einstein's general relativity., A force law that applies to the gravitational and electromagnetic forces in which the magnitude of the force decreases in proportion to the inverse of the square of the distance., Gravitational force decreases as one over distance squared (1/r²), where r is the distance from the source.