Title:
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Sets invariant under projections onto one dimensional subspaces (English) |
Author:
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Fitzpatrick, Simon |
Author:
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Calvert, Bruce |
Language:
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English |
Journal:
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Commentationes Mathematicae Universitatis Carolinae |
ISSN:
|
0010-2628 (print) |
ISSN:
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1213-7243 (online) |
Volume:
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32 |
Issue:
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2 |
Year:
|
1991 |
Pages:
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227-232 |
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Category:
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math |
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Summary:
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The Hahn--Banach theorem implies that if $m$ is a one dimensional subspace of a t.v.s. $E$, and $B$ is a circled convex body in $E$, there is a continuous linear projection $P$ onto $m$ with $P(B)\subseteq B$. We determine the sets $B$ which have the property of being invariant under projections onto lines through $0$ subject to a weak boundedness type requirement. (English) |
Keyword:
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convex |
Keyword:
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projection |
Keyword:
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Hahn--Banach |
Keyword:
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subsets of $\Bbb R^2$ |
MSC:
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46A55 |
MSC:
|
52A07 |
MSC:
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52A10 |
idZBL:
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Zbl 0756.52002 |
idMR:
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MR1137783 |
. |
Date available:
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2008-10-09T13:12:03Z |
Last updated:
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2012-04-30 |
Stable URL:
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http://hdl.handle.net/10338.dmlcz/116960 |
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Related article:
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http://dml.cz/handle/10338.dmlcz/116961 |
Related article:
|
http://dml.cz/handle/10338.dmlcz/118485 |
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Reference:
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[1] Schaeffer H.H.: Topological Vector Spaces.MacMillan, N.Y., 1966. MR 0193469 |
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