Skyrmions are topologically stable fields that cannot be smoothly deformed into any other field configuration that differs topologically or possesses a different integer topological invariant, the Skyrme number. They have been studied as full skyrmions in magnetic spin systems, and more recently as baby skyrmions in optical systems. Here, we introduce an optical analogy to magnetic skyrmions and demonstrate their dynamics within a magnetic field. Our optical skyrmions and synthetic magnetic field are both engineered using superpositions of Bessel-Gaussian beams, with time dynamics observed over propagation distance. We show that the Skyrmionic form changes during propagation, exhibiting controllable periodic precession over a well defined range, analogous to time varying spin precession in homogeneous magnetic fields. This local precession manifests as the global beating between skyrmion types, while still maintaining the invariance of the Skyrme number.
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