if I want to make sure that I am safe while out and about, would it be better for me to carry a gun or a?
grease fires have to be smothered
According to Einstein's general theory of relativity, gravity is what we call the curvature of space-time, and that curvature is caused by the presence of mass. In the words of John Archibald Wheeler, Mass tells space how to curve, and space tells matter how to move.
mass, energy, or both the presence of either one cause distortion in spacetime changing it from a euclidean space to non-euclidean (main point is straight lines aren't straight lines anymore through space AND time) rouse: the space-time distortion IS gravity. the question was what causes gravity, and that is what causes it. not what causes energy and mass to distort it in such a way
Also, the amount of gravity an object has is utterly unrelated to its SIZE; it is all about its MASS. You might have a dwarf star the size of the Earth (or even smaller) that has a gravitational field hundreds of times that of the Earth, because despite the fact that the two objects are of a similar size, the star is much denser than the Earth; that is, it contains much more mass.
..Gravity is caused by Electromagnetic pull No, this isn't correct. Gravity is caused by the presence of mass, like a star or planet, or even you and I Imagine a thin rubber sheet. Think of the sheet as space. Place a bowling ball on the sheet and a distortion in the sheet appears. Think of that distortion of gravity. If you place a golf ball inside the distortion (gravity) it will move down it and towards the bowling ball. Mass itself is just another form of energy. Remember E MC?, where 'E' is energy and 'M' is mass? That equation can be rewritten as M E / C?, meaning that if you have enough energy you'll get some mass. That should answer what causes mass..?
