Gravitational time dilation would seem to prevent anything from reaching the Schwarzchild radius. It seems to me that the calculation of properties of General Relativity would be similar to the Gausian calculation that asymptotes but never reaches unity (x axis). In other words, time dilation would approach 0 but never reach it. As mass approaches the Schwarzchild radius, spaghettification would stretch and rip apart everything from a human body to cells to molecules to atoms to hadrons and even quarks. Thus as the S surface is approached, matter becomes some sort of essence, nothing like particulate matter. Please, someone tell me if my thought process is somehow wrong in assuming that nothing could ever reach, much less pass, the Schwarzchild radius/surface. Note that although dimensions may change, it seems this view seems to apply to a Kerr, (spinning} black hole as well. An additional thought regarding spinners, it seems the tug of war between centrifugal and centripetal forces would use energy that would shrink the hole, as happens during LIGO events as binary black holes spin down.
2 Answers
First, remember that before there was a black hole, there was a star that collapsed into itself. John Wheeler, (who coined the term black hole) said that an imploding star converts its protons and neutrons into radiation during black hole formation. So now we are thinking along the lines of quarks and gluons. We know from the Pauli exclusion principle that spin 1/2 particles such as quarks cannot simultaneously occupy the same quantum state, so if there is a singularity at the centre, it can't be made of quarks. But spin 1 particles such as gluons can occupy the same quantum state without limit, so it is possible that a star's worth of gluons remains at the centre.
Carlo Rovelli (one of the key figures in Loop Quantum Gravity) has speculated that there is a Planck star in the centre of a black hole, so not a singularity but just a really small, compact mass.
However, for your general question about if time dilation prevents anything from penetrating the SR, there are many physicists who believe that there is nothing inside the event horizon; that it is just a hollow shell because time dilation stops any further movement towards the centre.
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That is why it is called an "Event" horizon: to come back out, you need to travel into your backwards like cone. Increasing your radial coordinate is like traveling to yesterday: the direction is not available.
It's well known that a free falling observer crosses the event horizon....un-eventfully. That a distance observer can never see it happen is not a problem.
Regrading centrifugal force: that is just no going to work in Kerr spacetime. There is a radius at which the force points inward; there are vortex lines forcing you to differentially rotate, and there is frame dragging which entrains you to move with the black hole, just to be "at rest".
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