University of Manchester researchers have found that graphene, the world’s thinnest material (a one-atom-thick gauze of carbon atoms), absorbs a well-defined fraction of visible light, which allows the direct determination of the fine structure constant (approximately 1/137), which defines the interaction between very fast moving electrical charges and electromagnetic waves.

The researchers found the carbon monolayer absorbs 2.3 percent of visible light. The experiments supported by theory show this number divided by Pi gives the exact value of the fine structure constant.