Removing hyper-regularity from HDX degree lower bounds
Determine whether the hyper-regularity assumption can be removed from the super-exponential degree lower bound proved for skeletons of Trickling-Down high dimensional expanders; specifically, prove analogous degree lower bounds for non-hyper-regular complexes (e.g., Ramanujan complexes) or develop a finer concentration framework that implies such bounds.
References
The best known constructions of high dimensional expanders are not hyper-regular. Is it possible to remove this constraint from our degree lower bound? While our technique holds even for `reasonably balanced' complexes, it cannot handle objects like the Ramanujan complexes have extremely unbalanced links. It seems likely this is a technical rather than inherent barrier, and we conjecture some finer notion of concentration or application thereof may be able to remove this constraint.