Going Through the Wall: Understanding Macroscopic Quantum Tunneling 1. Introduction: An Impossible Leap What if you threw a ball at a wall and it passed through to the other side without breaking it? In our everyday macroscopic world, this seems impossible. Walls are barriers, and objects bounce back when they hit them. But in the strange and fascinating microscopic world of quantum physics, particles sometimes do just that. They can "tunnel" through energy barriers as if they weren’t there. This phenomenon is called quantum tunneling . The 2025 Nobel Prize in Physics winners— John Clarke , Michel H. Devoret , and John M. Martinis —were honored for demonstrating this bizarre quantum behavior in a system large enough to hold in your hand. Their groundbreaking experiments showed for the first time that the rules of the quantum world are not limited to invisible atoms but can also manifest at our scale. Their work in the 1980s laid the foundation for the qubits that power to...