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Bounce, Don't Crunch Planck stars, or: the singularity that never was

Planck stars rewrite the black hole singularity as a quantum-gravity bounce - microseconds inside, eons outside, and possibly fixing physics' worst paradoxes.
Luitpold-Alexander Zollorsch
Luitpold-Alexander Zollorsch
@luitpold.me

Loop quantum gravity has this idea called a planck star, and it’s the most elegant fix to the black hole singularity problem I’ve come across:

Classical GR says a collapsing star can crunch down to a singularity – infinite density at a point, physics’ polite way of saying “the math broke”. Planck stars say nah. Once density hits planckian (5.1 × 10⁹⁶ kg/m³, comically extreme), quantum gravity kicks in, the inward pull gets balanced by a repulsive force, and the collapse halts. You get a stable-ish ball at planck density. Not point-sized either – density triggers it, not size. Could be macroscopic.

And it’s not stable forever. It’s mid-bounce. Microseconds in proper time, billions of years from outside thanks to time dilation. What we call a black hole is just a very slow ball hitting the floor. PBS Space Time breaks it down nicely.