Prices of a stock will move throughout the day. Investors generally buy a stock they feel is undervalued, and sell a stock they feel is overvalued. For instance, if the price of AAPL is $600 dollars, it means the cost to purchase one share of Apple is $600 dollars.
Einstein quickly realized (or had known all along) that his new theory of gravity was really a theory of the cosmos. In 1917, he wrote a famous paper applying general relativity to the universe as a whole. Today that paper stands as the foundation for modern cosmology.
Newton and Einstein's Theory of Gravity are defective in leaving out the vector energy in their Gravity Theory. The correct Theory of Gravity involves quaternion energy that consists of scalar energy and vector energy E= -mu/r + mcV. The Quaternion Theory of Gravity confirms Newton's Universal Law as opposed to Einstein's space warping Theory. Newton's law of Gravity involves matter creating forces that change motion and Einstein's Relativity involves matter warping space and changing motion. The Deflection of 1.7 seconds explained by Einstein as the result of curvature is better explained by Newton, where g is the earths gravity acceleration 9.8 m/s^2 and Rs= 150Gm distance to the sun and d the deflection due to the earth's gravity: