I never had a Plan this good.
Know your enemy
- Names: Earth, Terra, "the world"
- Age: 4,550,000,000 years
- Mass: 5,973,600,000,000,000,000,000 metric tonnes
- Radius: 6,371 kilometres (average)
- Surface gravity: 9.798 metres per second per second
- Escape velocity: 11,186 metres per second
You will need: a microscopic black hole.
Note that black holes are not eternal, they evaporate due to Hawking radiation. For your average black hole this takes an unimaginable amount of time, but for really small ones it could happen almost instantaneously, as evaporation time is dependent on mass. Therefore you microscopic black hole must have greater than a certain threshold mass, roughly equal to the mass of Mount Everest.
Creating a microscopic black hole is tricky, since one needs a reasonable amount of neutronium, but may possibly be achievable by jamming large numbers of atomic nuclei together until they stick. This is left as an exercise to the reader.
Method: simply place your black hole on the surface of the Earth and wait. Black holes are of such high density that they pass through ordinary matter like a stone through the air. The black hole will plummet through the ground, eating its way to the centre of the Earth and all the way through to the other side: then, it'll oscillate back, over and over like a matter-absorbing pendulum. Eventually it will come to rest at the core, having absorbed enough matter to slow it down. Then you just need to wait, while it sits and consumes matter until the whole Earth is gone.