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71.
Martingales valued in certain subspaces ofL
1 总被引:1,自引:0,他引:1
A Banach subspaceE ofL
1 is constructed such thatE fails the Radon-Nikodym property, yetE has no bounded dyadicδ-tree for anyδ>0. The unit ball ofE is also relatively compact in the topology of convergence in probability, which implies thatE has the strong Schur property. The construction uses martingales and probabilistic techniques.
Supported in part by NSF-MCS-7827056. 相似文献
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We present Doppler resolution limited spectra of the P(J) and R(J) multiplets for J ≦ 10 of the 10-μm CO stretch band of 12CD316OH using a tunable diode laser. Relative frequencies within the multiplets accurate to ±0.0002–0.0005 cm?1 are obtained, but no absolute frequencies are given. We are able to assign most of the hindered rotation and K substructure in these multiplets. The assignments are based on analyses of Stark-difference spectra combined with the ground-state microwave data and the intensity variations which are expected theoretically. The ground and excited state A, K = 1 asymmetry splitting parameters are measured to be δ1″ = (8.5450 ± 0.0080) × 10?3cm?1 and δ1′ = (9.7706 ± 0.0080) × 10?3cm?1, respectively. The ground-state value agrees well with the microwave results. A rapid-scan system for recording data and a computer-aided technique for calibrating and plotting the spectra are described. 相似文献
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Two operations on sets of bounded operators on Hilbert space are studied: One produces Jordan algebras and the other, its inverse in a certain sense, produces self-adjoint linear spaces. The question of which Jordan algebras arise from the first of these operations is investigated. It is shown that, in many cases, R has this property if and only if the complex associative algebra R + iR is equal to its double commutant. Thus, a by-product of the study is another approach to double commutant theorems. 相似文献
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A method is proposed for reducing the multi-dimensional Schrödinger equation to a one-dimensional integral equation. The reduction is exact; and the resulting integral equation although complicated, may be treated by any of a number of numerical methods. Two 2-dimensional problems, the harmonic oscillator and the S-limit for helium and one 3-dimensional problem, the helium ground state are treated in this way. 相似文献