# Contact

by Kevin Lin

This puzzle is based on one posed by the late Dr. Richard Feynman in one of his lectures:

Let's say you're a theoretical physicist who has just contacted an alien civilization using a brand new technology. Unfortunately, you can't figure out quite yet where your new alien friends live. They could be on the other side of the Galaxy, across the Universe, or even in another dimension.

But you start talking, starting first in the language of mathematics, then gradually working your way up to more complicated topics. After a while you come to understand that their world is more or less like ours. They have the same concepts of math and geometry, the same physical laws, and their world seems in many ways like ours. It has the same chemicals, and orbits a star with numerous other planets. And the aliens are far more advanced than us scientifically.

Eventually the aliens announce that they'd like to transport you over to their world. Ignoring the details of how they plan on accomplishing this (hypothetically assume "magic"), they would like to make you feel at home when you arrive.

So you starting telling the aliens everything you can about your home. Surprisingly, you discover that using only concepts built up from a shared understanding of math, physics, and chemistry, you can paint an amazingly detailed picture of life on Earth over time.

Assuming the aliens can build anything you can describe, and that you have the combined resources of all of Earth, could you theoretically describe your world well enough for you to survive on their world? Well enough that you couldn't tell the difference?