青海师范大学数学与统计学院, 青海 西宁 810008
朱彤(2002年生),女;研究方向:算子理论与算子代数; E-mail: zhutong@stu.qhnu.edu.cn
宋显花(1981年生),女;研究方向:算子理论与算子代数; E-mail: songxh@qhnu.edu.cn
收稿:2026-01-07,
修回:2026-05-24,
录用:2026-06-05,
网络首发:2026-07-08,
移动端阅览
朱彤, 宋显花. 投影对代数组合的谱和范数[J/OL]. 中山大学学报(自然科学版)(中英文), 2026,1-10.
Zhu Tong, Song Xianhua. Spectra and norms of algebraic combinations of projection pairs[J/OL]. Acta Scientiarum Naturalium Universitatis Sunyatseni, 2026, 1-10.
朱彤, 宋显花. 投影对代数组合的谱和范数[J/OL]. 中山大学学报(自然科学版)(中英文), 2026,1-10. DOI: 10.11714/acta.snus.ZR20260012.
Zhu Tong, Song Xianhua. Spectra and norms of algebraic combinations of projection pairs[J/OL]. Acta Scientiarum Naturalium Universitatis Sunyatseni, 2026, 1-10. DOI: 10.11714/acta.snus.ZR20260012.
首先研究Hilbert空间
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2.28600001
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上投影对
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的积
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,Jordan积
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,三乘Jordan积
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6.01133299
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,拟积
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15.83266735
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和Lie积
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的谱. 其次,研究了投影对线性组合
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的谱和范数. 同时,也得到了非零投影对的和、差、积,Jordan积及Lie积的范数之间的关系.
This paper first investigates the spectra of the product
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, Jordan product
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, triple Jordan product
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, quasi-product
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18.54199982
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and Lie product
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for pairs of projections
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on Hilbert space
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2.70933342
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. Secondly, it investigates the spectra and norms of the linear combination
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of projection pairs. Meanwhile, the relationships between the norms of the sum, difference, product, Jordan product and Lie product of non-zero projection pairs are also derived.
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