Molina Cardín, AlbertoDinis Vizcaíno, Luis IgnacioOsete López, María Luisa2024-12-182024-12-182021-03-01Molina-Cardín, Alberto, et al. «Simple Stochastic Model for Geomagnetic Excursions and Reversals Reproduces the Temporal Asymmetry of the Axial Dipole Moment». Proceedings of the National Academy of Sciences, vol. 118, n.o 10, marzo de 2021, p. e2017696118, https://doi.org/10.1073/pnas.20176961180027-842410.1073/pnas.2017696118https://hdl.handle.net/20.500.14352/112969We present a simple model for the axial dipole moment (ADM) of the geomagnetic field based on a stochastic differential equation for two coupled particles in a biquadratic potential, subjected to Gaussian random perturbations. This model generates aperiodic reversals and excursions separated by stable polarity periods. The model reproduces the temporal asymmetry of geomagnetic reversals, with slower decaying rates before the reversal and faster growing rates after it. This temporal asymmetry is possible because our model is out of equilibrium. The existence of a thermal imbalance between the two particles sets a preferential sense for the energy flux and renders the process irreversible.engAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/journal article1091-6490https://doi.org/10.1073/pnas.2017696118https://www.pnas.org/doi/10.1073/pnas.2017696118open access55536Geomagnetic reversalsStochastic modelTemporal asymmetryGeomagnetismPaleomagnetismGeofísicaFísica-Modelos matemáticos2507.01 Geomagnetismo y Prospección Magnética2507.04 Paleomagnetismo2205.10 Mecánica Estadística