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Massive Gauge Field Theory Without Higgs Mechanism II. Ward-Takahashi Identities and Proof of Unitarity

Jun-Chen Su
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Abstract

In our previously published papers, it was argued that a massive non-Abelian gauge field theory in which all gauge fields have the same mass can well be set up on the gauge-invariance principle. The quantization of the fields was performed by different methods. In this paper, It is proved that the quantum theory is invariant with respect to a kind of BRST-transformations. From the BRST-invariance of the theory, the Ward-Takahashi identities satisfied by the generating functionals of full Green's functions, connected Green's functions and proper vertex functions are successively derived. As an application of the above Ward-Takahashi identity, the Ward-Takahashi identity obeyed by the massive gauge boson propagator is derived and the renormalization of the propagator is discussed. Furthermore, based on the Ward-Takahashi identity, it is exactly proved that the S-matrix elements given by the quantum theory are gauge-independent and hence unitary.

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Jun-Chen Su. 2006-08-19. Massive Gauge Field Theory Without Higgs Mechanism II. Ward-Takahashi Identities and Proof of Unitarity. https://arxiv.org/abs/hep-th/9805192

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