👉 Tunnelling is a physical process in which matter moves through a closed channel, such as a tunnel or a pipe. This movement can be controlled by applying pressure to the walls of the channel, and it can also be influenced by other factors such as temperature, humidity, and flow rates. In general, tunnelling occurs when two materials are in thermal contact with each other at a critical point, where the material properties start to change significantly. This phenomenon is often studied using methods like X-ray
