In the trampoline demonstration representing space-time and gravity, it is obviously the friction between the trampoline and the ball that determines the path of the ball. Friction is a physical interaction, so space-time has to physically interact with matter for this demonstration to be a plausible description of what is happening actually. My question is, what is or what causes that physical interaction or “friction” between space-time and matter when space-time is curved?? Thank you

Asked Jason Omahne

Answer:

The trampoline is just an analogy to understand the phenomenon. Gravity is like the depression of the trampoline causing a curvature in the space time continuum.

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