The generalised Jacobson-Morosov theorem /

"The author considers homomorphisms H to K from an affine group scheme H over a field k of characteristic zero to a proreductive group K. Using a general categorical splitting theorem, André and Kahn proved that for every H there exists such a homomorphism which is universal up to conjugacy. Th...

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Bibliographic Details
Main Author: O'Sullivan, Peter, 1951-
Format: Book
Language:English
Published: Providence, R.I. : American Mathematical Society, 2010.
Series:Memoirs of the American Mathematical Society ; no. 973.
Subjects:
Description
Summary:"The author considers homomorphisms H to K from an affine group scheme H over a field k of characteristic zero to a proreductive group K. Using a general categorical splitting theorem, André and Kahn proved that for every H there exists such a homomorphism which is universal up to conjugacy. The author gives a purely group-theoretic proof of this result. The classical Jacobson-Morosov theorem is the particular case where H is the additive group over k. As well as universal homomorphisms, the author considers more generally homomorphisms H to K which are minimal, in the sense that H to K factors through no proper proreductive subgroup of K. For fixed H, it is shown that the minimal H to K with K reductive are parametrised by a scheme locally of finite type over k."--Publisher's description.
Item Description:"Volume 207, number 973 (third of 5 numbers)."
Physical Description:vii, 120 pages ; 25 cm.
Bibliography:Includes bibliographical references (page 117) and index.
ISBN:9780821848951 (alk. paper)
082184895X (alk. paper)
ISSN:0065-9266 ;