A team of physicists has achieved a groundbreaking feat by measuring the geometric 'shape' of a lone electron moving through a solid for the first time, providing novel insights into quantum behavior in crystalline solids. This was accomplished by measuring the quantum geometric tensor (QGT), a factor representing the full geometric details of a quantum state, using angle-resolved photoemission spectroscopy. This technique was applied to a cobalt-tin alloy, allowing researchers to compare theoretical and practical quantum geometries. Their method, possibly applicable to various materials, could advance the discovery of new properties like superconductivity, enhancing understanding within condensed-matter physics.