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arXiv · hep-th/0211258

O(3) Sigma model with Hopf term on Fuzzy Sphere

T. R. Govindarajan·E. Harikumar
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Abstract

We formulate the $O(3) \s-$ model on fuzzy sphere and construct the Hopf term. We show that the field can be expanded in terms of the ladder operators of Holstein-Primakoff realisation of SU(2) algebra and the corresponding basis set can be classified into different topological sectors by the magnetic quantum numbers. We obtain topological charge $Q$ and show that $-2j\le Q \le2j$. We also construct BPS solitons. Using the covariantly conserved current, we construct the Hopf term and show that its value is $Q^2$ as in the commutative case. We also point out the interesting relation of physical space to deformed SU(2) algebra.

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T. R. Govindarajan, E. Harikumar. 2003-01-29. O(3) Sigma model with Hopf term on Fuzzy Sphere. https://doi.org/10.1016/s0550-3213(03)00048-8

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