The Shapiro conjecuture generalizes this example, and it concerns all
questions of enumerating linear subspaces that are incident on other, fixed
subspaces in any vector space;
If the fixed subspaces are chosen tangent to a normal curve, then all
solutions will be real. When it was first made, this Shapiro conjecture seemed to good to be true (it is in fact false in its original generality). Nevertheless, proofs of special cases and a few million computatons together yielded overwhelming evidence for it. Work of Eremenko and Gabrielov, as well as Mukhin, Tarasov, and Varchenko (three papers in the Annals of Mathematics and JAMS) eventually proved the conjecture in the generality it could be true. Nevertheless, there are several appealing generalizations and corrections which are open. These have been formulated and studied by my research team over the past decade; These projects have used over 1.2 teraHertz-years of computation, looking at over 2.4 billion cases. This large-scale experimentation has involved 12 different people, including undergraduate students. |