There's a Euclid Living in the Monitor

There is a Euclid living in the monitor. He spent his whole life measuring the world and proving plane geometry, but before he died, he discovered that the sum of the interior angles of all triangles was a little more than 180 degrees. Is it a measurement error, or is the universe itself bending? Since then, Gauss, Riemann, Hubble, and Penrose have successively embarked on the path of seeking truth. They witnessed the expansion of space, the rise and fall of civilizations, and even found evidence of cosmic reincarnation. It wasn't until Euclid peeked outside the screen that he finally understood: The laws of the universe that they regard as truth may be just traces left by some giant creature.