Harald became the first of the Bohr brothers to earn a master's degree. Niels won his 9 months later. Students in his class were required to submit a thesis on a topic assigned by their supervisor. Bohr's supervisor was Christiansen, and the subject he proposed to them was the electronic theory of metals. Bohr then developed his master's thesis as part of his much larger theoretical "Doctor of Philosophy" thesis. He questioned the literature on the subject, relying on a model assumed by Paul Drude and elaborated by Hendrik Lorentz, which asserted that electrons are on a meta; are considered to behave like a gas. Bohr expanded Lorentz's model, but still unable to account for singularities such as the Hall effect, and decided that electronic theory could not fully explain the magnetic properties of metals. The theory was conducted in April 1911 and Bohr conducted his defense in May 1911. Bohr's thesis was revolutionary, but did not attract much attention outside Scandinavia because it was written in Danish, a requirement of the University of Copenhagen at the time. In 1921, Dutch physicist Hendrika Johanna van Leeuwen independently derived a theorem from Bohr's theory, today known as the Bohr−van Leeuwen theorem. In 1911, Bohr traveled to England, where most of the theoretical work on the structures of atoms was taking place. He met JJ Thomson of the Cavendish Laboratory and Trinity College, Cambridge. He attended lectures on electromagnetism given by James Jean and Joseph Larmor and decided to do some research on cathode rays, but failed to impress Thomson. He had more success with younger physicists like the Australian William Lawrence Bragg and the New Zealander Ernest Rutherford, whose 1911 Rutherford method on the atom had challenged...... middle of paper ..... .ns Cemetery in the Norrebro section of Copenhagen, with the remains of his previously deceased family. On October 7, 1965, the institute was officially renamed as it had been unofficially called: the Niels Bohr Institute. Although Bohr died, his legacy did not. In 1912 he and Margrethe married and shortly after the marriage they had children, they had 6 sons. The eldest son, Christian, died in a boating accident in 1934 and another Harald died of childhood meningitis. Aage Bohr became a very talented physicist, and in 1975 he also received the Nobel Prize in Physics, like his father. Hans Henrik became a doctor; Erik became a chemical engineer and Ernest became a lawyer. Each of the men followed in the footsteps of Bohr's men. Like Uncle Harald, Ernest Bohr became an Olympic athlete. He played field hockey for Denmark in the summer of 1948 in London..