To the best of our knowledge, we humans can only experience this world in three spatial dimensions: up and down, left and right, and forward and backward. In two physics labs, scientists have found a way to represent a fourth spatial dimension. “Maybe we can come up with new physics in the higher dimension and then design devices that take advantage the higher-dimensional physics in lower dimensions.” Perhaps by observing some real-world physical system, we can learn about a fourth-dimensional nature by a shadow left in lower dimensions.
At each of the new experiments’ core is the quantum Hall effect: When electrons are confined to two dimensions, as if they are stuck on the surface of a sheet of paper, and a magnetic field is passed through that sheet perpendicularly, some of the system’s electrical properties become restricted to multiples of exact number values.
An extra parameter based on the internal behavior of these atoms is coded along each dimension, playing the role of two more spatial dimensions.
“There’s another question of whether real solid-state materials with complex unit cells have these hidden dimensions, and if their physics can be understood in higher dimensional physics that wasn’t accessible before,” said Rechtsman.