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arXiv · hep-th/0006227

BRST invariant $CP^{1}$ model through improved Dirac quantization

Soon-Tae Hong·Young-Jai Park·Kuniharu Kubodera·Fred Myhrer
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Abstract

The Batalin-Fradkin-Tyutin (BFT) scheme, which is an improved version of Dirac quantization, is applied to the $CP^1$ model, and the compact form of a nontrivial first-class Hamiltonian is directly obtained by introducing the BFT physical fields. We also derive a BRST-invariant gauge fixed Lagrangian through the standard path-integral procedure. Furthermore, performing collective coordinate quantization we obtain energy spectrum of rigid rotator in the $CP^1$ model. Exploiting the Hopf bundle, we also show that the $CP^1$ model is exactly equivalent to the O(3) nonlinear sigma model at the canonical level.

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Soon-Tae Hong, Young-Jai Park, Kuniharu Kubodera, Fred Myhrer. 2001-07-02. BRST invariant $CP^{1}$ model through improved Dirac quantization. https://doi.org/10.1142/s0217732301004601

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