What if we made a tunnel along the diameter of the Earth?

If we could build a tunnel that would cross the Earth, saving the small detail of the temperatures and liquid state of part of the nucleus, we would be facing the most energy efficient means of transport. The videos ‘And yes...’ raise fictitious questions but that allow us to learn a lot about the world in which we live. They have been broadcast in the scientific dissemination program of Televisión Española Orbita Laika, and produced in collabor…