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200
Ptolemy
He stated that the earth was the center of the universe and that all of the planers revolved around the earth in perfect circles. He keeps this idea while experimenting his hypothesis and even though he gets clues that he is incorrect he passes them by and continues to explore his idea. -
332
Aristotle
He created the Aristotelian theory of gravity which said that all bodies move towards their natural place which is the center of the earth. His theory was used until it was proven wrong after Newton’s and others theories. -
Isaac Newton
Discovered how gravity acted upon various objects. It hit him when he was sitting on the ground under an apple tree and an apple fell which made him wonder what made it fall. He made several experiments involving a cannon ball to see the effects of gravity on the ball. He also agreed with Kepler in the idea that the planets moved in ellipses and not in perfect circles around the sun. -
Henry Cavendish
Made the first accurate measurement of the density of the earth; he also did the measurement of the gravitational constant the Newton had earlier made. He experimented using a torsion balance to get an approximate measurement. -
Albert Einstein
Published Special Theory of Relativity which said that space and time are not separate. His theory made Newton’s laws incorrect. He stated the principle of equivalence so in a gravitational field the volume at each end is the same.
