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. In 1914, Nordström added a space dimension to his theory. This described gravity and electromagnetism at the same time. Unluckily, Theodor Kaluza and Oskar Klein have got most attetion on this subject. Nordström is not well known in his own home country, but what he has done is known well in other countries. Some Finnish authors call Nordström as "Finnish Einstein".