Microcausality of scalar field on noncommutative spacetime
نویسنده
چکیده
We analyze the microcausality of free scalar field on noncommutative spacetime. To adopt the usual Lorentz invariant spectral measure, through the result of the expectation values of the Moyal commutators, for the quadratic operators such as φ(x) ⋆ φ(x), π(x, t) ⋆ π(x, t), ∂iφ(x, t) ⋆ ∂iφ(x, t), and ∂iφ(x, t) ⋆ π(x, t), we obtain that for the case θ = 0 of the spacetime noncommutativity, the microcausality of free scalar field is satisfied. For the case θ 6= 0 of the spacetime noncommutativity, the microcausality of free scalar field is violated. PACS numbers: 11.10.Nx, 03.70.+k
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