What classical physics says about a singularity

Verification: The claim combines a classical prediction with an unsupported assertion. In the classical description, general relativity predicts a singularity where spacetime curvature (and in simple models density) becomes formally infinite. This is often interpreted as a limit of the theory, since quantum effects should matter. But established physics does not say that matter is compressed to exactly the Planck length; describing a black hole’s center requires a quantum theory of gravity that we do not yet have.

Conclusion: “Infinite density” is a classical mathematical prediction of a singularity, not a confirmed description of the actual center. The Planck length is not an established size for compressed matter.