Star-products, spectral analysis, and hyperfunctions
Star-products, spectral analysis, and hyperfunctions
复制标题
明星产品、光谱分析和超函数
DOI:
10.1007/978-94-015-1276-3_16
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发表时间:
2000
期刊:
影响因子:
--
通讯作者:
José Silva
中科院分区:
文献类型:
--
作者:
Carlos Moreno;José Silva
We study the ⋆-exponential function U(t;X) of any element X in the affine symplectic Lie algebra of the Moyal ⋆-product on the symplectic manifold (ℝ × ℝ;ω). When X is a compact element, a natural specific candidate for U (t;X) to be the exponential function is suggested by the study we make in the non-compact case. U (t;X) has singularities in thetvariable. The analytic continuation U(z;X),z = t + iy, defines two boundary values δ+U (t;X) = limy↓0U(z;X) and δ-(t;X) = limy↑0U(z; X). δ+U (t;X) is a distribution while δ-U (t;X) is a Beurling-type, Gevrey-class s — 2 ultradistribution. We compute the Fourier transforms in t of δ±U (t;X). Both Fourier spectra are discrete but different (e.g. opposite in sign for the harmonic oscillator). The Fourier spectrum of δ+U(t;X) coincides with the spectrum of the self adjoint operator in the Hilbert spaceL2(ℝ) whose Weyl symbol is X. Only the boundary value δ+U(t;X) should be considered as the ⋆-exponential function for the elementX, since δ-U(t;X) has no interpretation in the Hilbert spaceL2(ℝ).