Browse/search for people

Publication - Professor Sir Michael Berry

    Pumping a swing revisited

    Minimal model for parametric resonance via matrix products

    Citation

    Berry, MV, 2018, ‘Pumping a swing revisited: Minimal model for parametric resonance via matrix products’. European Journal of Physics, vol 39.

    Abstract

    A child rises on a swing by changing the length of its chain. This is explained by the mathematical fact that the product of two elliptic symplectic matrices can be hyperbolic. The connection could be helpful in teaching both mechanics and matrices. A Hamiltonian formulation avoids an error. Random swinging is unlikely to succeed.

    Full details in the University publications repository