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e2m2a
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The classical paradigm of how an object acquires gravitational potential energy goes like this: First, we take the case where the object is near the surface of the Earth which we define as the zero reference point. The object has a mass of 1 kg. We lift the object by an agent, such as a hand, 1 meter above the surface, and we can account for the 9.8 joules of gpe that object has acquired. It acquired its gpe by the work done on the object by the external agent, the hand. If we release the object, the gpe of the object is converted to kinetic energy on its way down, and by the time it hits the surface of the earth, the object has acquired 9.8 joules of kinetic energy by the conservation of mechanical energy. Thus, all the energy is accounted for, everything balances out, no energy was created out of nothing. The object acquired gpe by the work done on it. Except--take the case where the object is not near the surface of the Earth initially, but at the outer reaches of the universe, such as a cosmic particle heading toward the earth. Here, we must use a different approach, setting infinity as the zero reference point. However, there is no change in the pe to ke conversion paradigm, for as the particle streams toward the earth, the gpe decreases (its negative value increases) and a corresponding increase in kinetic energy must occur in addition to its initial kinetic energy. By the time it hits the surface of the earth, all of the energy can be accounted for. Or can it? What agent "lifted" the cosmic particle out to infinity or did work on the particle to give it its initial increase in gpe (its negative value decreased) in the first place? Work had to be done on the particle by the classical paradigm to account for the particle's initial gpe if the conservation of energy is to remain intact. If no agent can be practically accounted for, then the particle must have acquired its gpe soley by the action of the gravitational field of the Earth on the particle. Does this mean gravity, the curvature of space-time, creates energy out of nothing?