The Moving Sofa Problem: How a Hallway Corner Was Finally Solved

14/01/2026 4 min
The Moving Sofa Problem: How a Hallway Corner Was Finally Solved

Listen "The Moving Sofa Problem: How a Hallway Corner Was Finally Solved"

Episode Synopsis

A legendary geometry puzzle asks for the largest 2D sofa that can round a right-angle hallway corner. We trace the journey from Moser and Hammersley’s early bounds to Gerver’s iconic handset-shaped sofa, and finally Jin-Hyun Baek’s 2024 proof using enclosing shapes that pin down the exact maximum at 2.2195 square units. Along the way, we connect this centuries-spanning debate to modern motion planning in robotics and medicine, showing how a stubborn hallway can reveal fundamental limits of movement.Note: This podcast was AI-generated, and sometimes AI can make mistakes. Please double-check any critical information. Sponsored by Embersilk LLC