The concept he believed in was that physical properties at the atomic level would be perceived differently depending on experimental factors, thus explaining why light could be considered both a particle and a wave . Bohr began working with the group of scientists who were at the forefront of nuclear fission research in the late 1930s, when he contributed to the theory of liquid droplets. In addition to his scientific theories, Bohr was known for his intelligence and kindness. In 1920, Bohr founded the University Institute of Theoretical Physics which he directed until the end of his career. Bohr's own theory led him to theorize in a series of papers that atoms emit electromagnetic radiation as a result of electrons jumping to different orbital levels. Bohr's work on atomic structures earned him the Nobel Prize in