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Relativity FAQ

The Schwarzschild event horizon at r = 2GM/c^2 is:

A coordinate singularity for Schwarzschild coordinates. For Schwarzschild coordinates the horizon is a coordinate singularity, while the true curvature singularity lies at r = 0.

Short Answer

A coordinate singularity for Schwarzschild coordinates is the best answer.

Relativity questions test whether space, time, energy, and simultaneity are being treated classically when they should not be. Start by deciding whether the question is special relativity, general relativity, or an observational consequence such as GPS timing.

For Schwarzschild coordinates the horizon is a coordinate singularity, while the true curvature singularity lies at r = 0.

Why This Answer Is Correct

This is a Hard-level question in Relativity. The prompt is really testing whether you can connect the concept to its defining physical relationship instead of picking a nearby-but-wrong term.

Most relativity mistakes come from mixing Newtonian intuition with relativistic invariants such as spacetime interval, proper time, or rest energy.

Choices At A Glance

  • A. A true physical singularity
  • B. A coordinate singularity for Schwarzschild coordinates
  • C. The location where curvature becomes infinite
  • D. Present only for rotating black holes

When similar options appear on an exam, eliminate the ones that break the core law, use the wrong units, or confuse a definition with a consequence.

Topic Snapshot

Topic: Relativity

Difficulty: Hard

Best next move: Re-state the governing law in your own words, then solve one more example from the same topic before moving on.