According to general relativity, the reason the Earth goes around the Sun rather than flying off into space is not because there is a force that pulls it around in an orbit. It goes around the Sun because the space around the Sun is distorted in such a way that what feels like a straight line to the Earth is actually a circle (or an ellipse). In this scenario, gravitational mass is not a charge that some particles have and others don’t; rather it is a measure of how much an object is capable of distorting the space around it. As bizarre as this theory may sound, it’s been very successful at
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