Complex sentence: Freeman John Dyson (born 15 December 1923) is an English-born American theoretical physicist and mathematician, known for his work in quantum electrodynamics, solid-state physics, astronomy and nuclear engineering.
Split into simpler sentences: Freeman John Dyson (born 15 December 1923) is an English-born American theoretical physicist and mathematician. He is known for his work in quantum electrodynamics, solid-state physics, astronomy and nuclear engineering.