# Hiroshi Enatsu

Hiroshi Enatsu
BornSeptember 12, 1922
Miyakonojō, Japan
DiedAugust 4, 2019 (aged 97)
Kyoto, Japan
NationalityJapan
CitizenshipJapanese
Alma materKyoto University
Scientific career
FieldsTheoretical physics
Institutions
• Kyoto University
• Columbia University
• Niels Bohr Institute
• Ritsumeikan University
InfluencesNiels Bohr

Hiroshi Enatsu (12 September 1922 - 4 August 2019) was a Japanese theoretical physics who contributed to a special relativity Hamiltonian mechanics formalism in quantum field theory.

Enatsu has found [1]that the Canonical commutation relation [2] $[\psi (x, \tau), \psi ^*(x', \tau)] = \delta ( x - x' )$ in a relativistic Hamiltonian formalism is equivalent to that in the conventional non-relativistic Hamiltonian formalism of quantum field theory, where $[\psi, \phi] = \psi \phi - \phi \psi$ is the commutator, $x$ is spacetime coordinates, $\tau$ is proper time, $\psi ^*$ is Hermitian adjoint of $\psi$, and $\delta (x)$ is the Dirac delta function, with the aid of the relation $\epsilon ( x - x' ) \epsilon ( \tau - \tau' )=1$.

## Biography

• 1922 born on September 12 in Miyakonojō as a son of Eizo and Fumi (Kuroiwa) Enatsu
• 1944 received Bachelor of Science from Kyoto University
• 1953 received Doctor of Science [3] from Kyoto University
• 1946 - 1957 assistant at Kyoto University[4][5]
• 1952 - 1953 research assistant at Columbia University [6] in New York City
• 1955 - 1956 visiting member of the Institute for Theoretical Physics in Copenhagen[7][8]
• 1957 assistant professor and inaugurated a professor at Ritsumeikan University in Kyoto
• 1971 to 1972 the Dean of faculty of science and engineering at Ritsumeikan University
• 1988 retired from a professor at Ritsumeikan University in Kyoto, and has been a professor emeritus
• 2019 died on 4 August in Kyoto [9]