Title:
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Remarks on Fréchet differentiability of pointwise Lipschitz, cone-monotone and quasiconvex functions (English) |
Author:
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Zajíček, Luděk |
Language:
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English |
Journal:
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Commentationes Mathematicae Universitatis Carolinae |
ISSN:
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0010-2628 (print) |
ISSN:
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1213-7243 (online) |
Volume:
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55 |
Issue:
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2 |
Year:
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2014 |
Pages:
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203-213 |
Summary lang:
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English |
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Category:
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math |
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Summary:
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We present some consequences of a deep result of J. Lindenstrauss and D. Preiss on $\Gamma$-almost everywhere Fréchet differentiability of Lipschitz functions on $c_0$ (and similar Banach spaces). For example, in these spaces, every continuous real function is Fréchet differentiable at $\Gamma$-almost every $x$ at which it is Gâteaux differentiable. Another interesting consequences say that both cone-monotone functions and continuous quasiconvex functions on these spaces are $\Gamma$-almost everywhere Fréchet differentiable. In the proofs we use a general observation that each version of the Rademacher theorem for real functions on Banach spaces (i.e., a result on a.e. Fréchet or Gâteaux differentiability of Lipschitz functions) easily implies by a method of J. Malý a corresponding version of the Stepanov theorem (on a.e. differentiability of pointwise Lipschitz functions). Using the method of separable reduction, we extend some results to several non-separable spaces. (English) |
Keyword:
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cone-monotone function |
Keyword:
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Fréchet differentiability |
Keyword:
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Gâteaux differentiability |
Keyword:
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pointwise Lipschitz function |
Keyword:
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$\Gamma$-null set |
Keyword:
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quasiconvex function |
Keyword:
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separable reduction |
MSC:
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46G05 |
MSC:
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47H07 |
MSC:
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49J50 |
MSC:
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58C20 |
idZBL:
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Zbl 06391538 |
idMR:
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MR3193926 |
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Date available:
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2014-06-07T15:36:09Z |
Last updated:
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2016-07-01 |
Stable URL:
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http://hdl.handle.net/10338.dmlcz/143802 |
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Reference:
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