Explore a groundbreaking development in graph theory with this Numberphile video featuring Erica Klarreich. Delve into the counterexample to Hedetniemi's conjecture, a long-standing problem in mathematics. Learn about graph coloring, tensor products, and the significance of this breakthrough. Discover how Yaroslav Shitov's paper disproved the conjecture and its implications for the field. Gain insights into the history of the problem through photos and pages from Stephen Hedetniemi's original dissertation. Connect this topic to other graph theory concepts explored in previous Numberphile videos, such as four-color maps, planar graphs, and perfect graphs. Enhance your understanding of complex mathematical ideas presented in an accessible and engaging manner.