A Science Odyssey Guest 3 wearing an Albert Einstein mask

How do you define gravity?

Gravity is nothing more than the curvature of the space-time continuum. Perhaps you are intimidated by the term space-time continuum. You needn't be. All it describes is our familiar three-dimensional world, plus a fourth dimension: time.

In our four-dimensional universe, space "curves" around objects, such as the Sun. The more massive, or heavy, the object, the more space curves around it. Our Earth, as well as the other planets, is merely following a path that is determined by this curvature. You could even say that the Earth is following the path of least resistance as it travels around the Sun.

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