Original: Gunnar Nordström (12 March 1881, Helsinki 24 December 1923, Helsinki) was a Finnish theoretical physicist who is best remembered for his theory of gravitation, which was an early competitor of general relativity.
Simplified: Gunnar Nordström (12 March 1881, Helsinki 24 December 1923, Helsinki) was a Finnish physicist. He is best known for his theory of gravitation, which was a competitor of Albert Einstein's general relativity.