引力如何產生?

引力是不是能量的一種？This depends on how you think. If a satellite is moving towards the earth, the gravitational force ,F=Gm1m2/R2, can change into kinetic energy. Since the change of PE converts into KE.

能量不是conserved的嗎 Yes. It is a conserved force.

為何地球的引力是無中生有??No, your concept is wrong! The gravitational force地球的引力is due to the distortion of the space因空間扭曲而成,？能量由那裡transfer的. 對不起,我也不懂.

2007-01-22 17:59:53 補充：
你可以想像有一履很大的布,四周被四個人用力地拉着,現在叫一個人放一個大鐵球(好比太陽,因為質量最大)到布中間,它的中心會下陷,如果你現在放一個小球(好比地球)於這布的邊緣,這個小球就會look向這個大球好像被重力吸引一樣,這個模型解釋了何謂"空間扭曲而成"質量最大的太陽造成了空間扭曲的現象

Gravitational force is a FORCE, not a kind of energy. When this force does work, energy is produced. An example is the production of electricity in hydro-eelctric power station.

The origin of gavitational force is still awaiting discovery. General relativity tells that its presence is because of space warping due to the presence of mass. Quantum theory points to the presence of gravitons, which is responsible for the gravitational attraction between two objects.