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What causes the Sun’s 11-year sunspot cycle?

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Illustration showing the eight planets of the solar system in order from the Sun-Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune-depicted to scale by size, with labeled diameters in miles and kilometers. The Sun is partially visible on the left for comparison. — Solar system The planets (in comparative size) in order of distance from the Sun.

The exact origin of the 11-year sunspot cycle remains unknown to science. While the phenomenon is impressively regular, there is no established reason why a star in radiative equilibrium should produce such cycles.1

Current scientific understanding suggests that the cycle is driven by the interaction of magnetic flux loops and the Sun's internal motions. Because the convective zone is too chaotic to produce the observed regularity, most models of the solar dynamo focus on the Sun's differential rotation—the fact that the Sun rotates faster at its equator than at higher latitudes. It is theorized that this differential rotation winds and enhances magnetic field lines in a regular manner.1

During the cycle, magnetic flux emerges as sunspot pairs. As these spots decay, the magnetic flux is transported toward the poles, eventually reversing the Sun's global magnetic field. This process leads to a 22-year complete magnetic cycle, as the magnetic polarity configuration reverses every 11 years. However, the fundamental reason for the Sun's differential rotation itself remains a mystery.123