Dear Dr. Corda, and colleagues,
My condolences for Dr. Leiter, whom I admire from previous fqxi essay contests. Your essay is very compelling, and one should not exclude the possibility that singularities and horizons don't actually exist. I think you are doing an important job by exploring this possibility. Being more intimidated by theorems of Penrose, Hawking, Christodoulou, and Klainerman, I took the complementary task to consider the singularities as inevitable, and see what happens. In my essay "Did God divide by zero?" I show that nothing that bad as expected, that black hole and big bang singularities not only are benign, but even introduce a metric dimensional reduction which may help at the quantization of gravity. So if the singularities will turn out to exist, I hope to provide a safety net with my approach. I would appreciate feedback to my essay, if you find time for this.
On the other hand, you may very well be right and nothing like singularities is admitted in reality. It may be possible that the strong equivalence principle be ensured by global consistency. I use global consistency in "Global and local aspects of causality" (independent of this contest's essay), to make quantum mechanics more reasonable and more compatible with general relativity.
Best wishes,
Cristi Stoica