The end of spacetime in black hole

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This video explains the concept of a black hole, focusing on how gravity affects spacetime and how increasing mass influences the structure of spacetime. Traditionally, black holes are known as objects from which nothing, not even light, can escape, with a central "singularity" where gravity becomes infinitely strong. This video uses a thought experiment to illustrate gravitational effects, imagining an apple falling through a well drilled to the Earth's center, where opposing gravitational forces would balance and the apple would oscillate back and forth.

This visualization helps us understand spacetime’s curved nature. Spacetime is depicted as a cylinder when gravity is minimal but transforms into a cone shape as gravity strengthens, such as near Earth’s surface. Objects in spacetime follow paths determined by this curvature rather than by any external force.

If Earth's mass grew indefinitely, gravity would slow time down to a stop, creating a black hole where all motion ceases, trapping everything. This happens because increasing mass flares the spacetime surface, and at an infinite flare, time halts, creating an inescapable trap—a black hole. Thus, black holes illustrate extreme spacetime curvature, beyond which nothing can escape.

An observer would see an astronaut falling endlessly, seemingly approaching the black hole’s horizon forever. Although the path to infinity appears infinitely long, it only requires a 90-degree turn along the curved spacetime surface to reach the horizon, marking the endpoint of spacetime within a black hole.

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