Complex sentence: Aberration became a problem in electromagnetic theory after the discovery of the electromagnetic nature of light and many scientists thus sought to unify electromagnetism with the aether drag theories, culminating Hendrick Lorentz' electromagnetic aether theory in 1892.
Split into simpler sentences: Aberration became a problem in electromagnetic theory with the discovery of the electromagnetic nature of light. Many scientists sought to to solve this with a unified theory electromagnetism and aether drag, culminating Hendrick Lorentz' electromagnetic aether theory in 1892.