RT Journal Article T1 Deterministic chaos in the elastic pendulum: a simple laboratory for nonlinear dynamics A1 Fernández-Rañada, Antonio AB The chaotic motion of the elastic pendulum is studied by means of four indicators, the Poincare section, the maximum Lyapunov exponent, the correlation function, and the power spectrum. It is shown that for very low and very large energies the motion is regular while it is very irregular for intermediate energies. Analytical considerations and graphical representations concerning the applicability of KAM theorem are also presented. This system and the type of description used are very suitable to introduce undergraduate students to nonlinear dynamics. PB American Association of Physics Teachers SN 0002-9505 YR 1992 FD 1992-01 LK https://hdl.handle.net/20.500.14352/59016 UL https://hdl.handle.net/20.500.14352/59016 LA spa NO © 1992 American Association of Physics Teachers. Two of the authors (RC and JJR) acknowledge A. Muñoz and L.A. Fernández for their encouragement, and A. Sánchez for his help in typing this manuscript. DS Docta Complutense RD 6 jul 2025