Christian Møller (22 December 1904 in Hundslev, Als – 14 January 1980 in Ordrup) was a Danish chemist and physicist who made fundamental contributions to the theory of relativity, theory of gravitation and quantum chemistry.^[1] He is known for Møller–Plesset perturbation theory^[2] and Møller scattering.

His suggestion in 1938 to Otto Frisch that the newly discovered process of nuclear fission might create surplus energy, led Frisch to conceive of the concept of the nuclear chain reaction, leading to the Frisch–Peierls memorandum, which kick-started the development of nuclear energy through the MAUD Committee and the Manhattan Project.^[3]

Møller was the director of the European Organization for Nuclear Research (CERN)'s Theoretical Study Group between 1954 and 1957 and later a member of the same organization's Scientific Policy Committee (1959-1972).^[4]

In 1961, Møller^[5][6] showed that a tetrad description of gravitational fields allows a more rational treatment of the energy–momentum complex than in a theory based on the metric tensor alone. The advantage of using tetrads as gravitational variables was connected with the fact that this allowed to construct expressions for the energy-momentum complex which had more satisfactory transformation properties than in a purely metric formulation.

Subrahmanyan Chandrasekhar came up with his theory of the Chandrasekhar limit for the maximum stable mass of a star, in 1930. This calculation was in opposition to Sir Arthur Eddington theories about stars. Eddington mocked Chandrasekhar various times and frequently campaigned against Chandrasekhar during conferences.^[7]

In 1935, Møller was the first to write a paper in collaboration with Chandrasekhar to criticise Eddington's theory. They wrote "we are quite unable to follow [Eddington's] arguments." They also proceeded to refute Eddington's follow up paper showing contradictions in his theory.^[7]

• The world and the atom, London, 1940.^[8]
• The theory of relativity, Clarendon Press, Oxford, 1972.
• A study in gravitational collapse, Kobenhavn : Munksgaard, 1975.
• On the crisis in the theory of gravitation and a possible solution, Kobenhavn : Munksgaard, 1978.
• Evidence for gravitational theories (ed.), Academic Press, 1963.
• Interview with Dr. Christian Moller by Thomas S. Kuhn at Copenhagen July 29, 1963 Archived January 12, 2015, at the Wayback Machine Oral History Transcript — Dr. Christian Moller

• Born rigidity
• Proper reference frame (flat spacetime)