Can neutrons be located at a different place than their own
spin? A quantum experiment, carried out by a team of researchers from the
Vienna University of Technology, demonstrates a new kind of quantum paradox.
The Cheshire Cat featured in Lewis Caroll’s novel “Alice in
Wonderland” is a remarkable creature: it disappears, leaving its grin behind.
Can an object be separated from its properties? It is possible in the quantum
world. In an experiment, neutrons travel along a different path than one of
their properties – their magnetic moment. This “Quantum Cheshire Cat” could be
used to make high precision measurements less sensitive to external
perturbations.