周金秋,曹文勝
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關(guān)于四元數(shù)M?bius變換的分類判別
周金秋,曹文勝
(五邑大學(xué) 數(shù)學(xué)與計算科學(xué)學(xué)院,廣東 江門 529020)
基于變換作用和等距球的性質(zhì),得到了變換的一個分解. 利用旋轉(zhuǎn)與對應(yīng)的變換不動點(diǎn)的關(guān)系,得出四元數(shù)變換是橢圓變換和拋物變換的充分必要條件.
四元數(shù);變換;等距球;不動點(diǎn)
下面給出基于不動點(diǎn)個數(shù)和右特征值模的元素分類.
2 幾則引理
是的一個不動點(diǎn),則有:
.
故而
是橢圓的或拋物的,則有:
3 主要結(jié)論及證明
是規(guī)范的且,那么是橢圓的當(dāng)且僅當(dāng),并且.
變形得:
代入式(5)得:
是規(guī)范矩陣且,那么是拋物的當(dāng)且僅當(dāng),并且.
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[責(zé)任編輯:熊玉濤]
On the Classification of QuaternionicTransformations
ZHOUJin-qiu, CAOWen-sheng
(School of Mathematics and Computational Science, Wuyi University, Jiangmen 529020, China)
Based on the action oftransformations and the property of its isometric spheres, we obtain a decomposition oftransformation. By using the relationship of the fixed points of the rotation partand, we obtain the sufficient and necessary conditions for elliptic transformations and parabolic transformations.
quaternion;transformation; isometric spheres; fixed points
1006-7302(2015)02-0001-05
O151.21
A
2014-10-24
國家自然科學(xué)基金資助項目(10801107)
周金秋(1988—),女,江西吉安人,在讀碩士生,研究方向為復(fù)分析;曹文勝,教授,博士,碩士生導(dǎo)師,通信作者,研究方向為復(fù)分析.