No, it probably can not be a chemical rocket. Nuclear, yes. My point is that we are in the realm of just needing new engineering (how to make nuclear reactions

No, it probably can not be a chemical rocket. Nuclear, yes. My point is that we are in the realm of just needing new engineering (how to make nuclear reactions, or even antimatter-matter collision work for this goal), not new science (warp drives, something else we don't understand about space or gravity, or mass).