Mathematicians Build Long-Awaited Graph Sandwich

Mathematicians have finally proved a 22-year-old conjecture about "graph sandwiches," which involves positioning a complex graph between two simpler graphs to understand its properties. The proof, completed in 2025 by three mathematicians, demonstrates that any sufficiently large graph of a certain type can be sandwiched this way, revealing deeper connections between two different random mathematical processes. This breakthrough provides researchers with a new tool for analyzing complex networks found in social systems, the internet, and biological systems.