I distinctively remember my General Relativity classes.
Every one of them was a joyful experience, and yet I often came home frustrated because I hadn’t understood a particular equation, mathematical reasoning or structure that day. Even so, the feeling of anticipation was nearly overwhelming. A great and beautiful mystery was increasingly within my grasp, if only I could reach out beyond what felt like a mental fog clouding my understanding.
This was not just any mystery. General Relativity is a theory of space-time. It describes the very “stuff” which surrounds us, the reality we are probably a part of.
According to this theory, mass and energy curve the very fabric of reality1. Straight lines are bent, and are renamed as geodesics. In the absence of any external force, objects simply follow these geodesics2. Physicist John Wheeler put it well when he said, “Matter tells space how to curve, and space tells matter how to move.” So, for instance, the trajectory Earth follows around the sun is actually a geodesic––an otherwise …
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