Workshop on Geometric Structures on 3-manifolds

By constructing certain immersed $\pi_1$-injective 2-complexes in closed hyperbolic 3-manifolds, we show the following statement: For any closed oriented hyperbolic 3-manifold $M$, and any closed oriented 3-manifold $N$, $M$ admits a finite cover $M'$ such that there exists a degree-2 map $f : M' \to N$, i.e. $M$ virtually 2-dominates $N$.