Credit: ALAMY

Phys. Rev. E 78, 036207 (2008)

Gamblers — and Einstein — have assumed that throwing a die gives a random result. But does it? Jan Nagler of the Max Planck Institute for Dynamics and Self-Organization in Göttingen and Peter Richter of the University of Bremen in Germany have simplified the throw of a die to the two-dimensional case of a dumb-bell tossed onto a surface. Will it fall with one labelled end pointing to the left or to the right?

The researchers calculated the dynamics and find that these are only truly chaotic, leading to complete randomness, for certain initial conditions: for example, if the object is cast from a roughly upright position with enough energy. A skilled thrower, they say, could have a good chance of manipulating these conditions to bias the probable outcome.