Wonky shapes can be made to roll along a specific path of your choice

Wonky spheres could be sculpted to roll eternally downhill alongside any doable path, so long as the trail repeats. These “trajectoids” might be used to design robots that comply with specific routes, or to mannequin how the spin of quantum laptop bits, known as qubits, will change over time.

Most objects, equivalent to spheres or tyres, will roll down a easy hill in a straight line. There are some objects that hint curved paths – equivalent to oloids, three-dimensional objects shaped from …