Journal of Mathematical Physics

Quantum transformation theory in fermion Fock space

Yong-de Zhang, Zhong Feng Tang

Published Dec 1, 1993• 21 citations

Abstract

In this article a general linear quantum transformation U for the following fermion system with n modes, (b′+,b̃′)=U(b+,b̃)U−1=(b+,b̃)(B̃, A, C̃D), is studied. All above transformations in Fock space are proved to form a ray representation of a group which is isomorphic with O(2n,C). The explicit expressions of operator U in terms of the normal ordered product and non-normal ordered product are obtained. A series of auxiliary identities are given. It has been mentioned that the results are applicable to the case of fermion fields with interaction.

DOI: 10.1063/1.530274

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