This is an announcement for the paper "On separable determination of
sigma-P-porous sets in Banach spaces" by Marek Cuth, Martin Rmoutil,
and Miroslav Zeleny.
Abstract: We use a method involving elementary submodels and a partial
converse of Foran lemma to prove separable reduction theorems concerning
Suslin sigma-P-porous sets where "P" can be from a rather wide class
of porosity-like relations in complete metric spaces. In particular, we
separably reduce the notion of Suslin cone small set in Asplund spaces. As
an application we prove a theorem stating that a continuous approximately
convex function on an Asplund space is Frechet differentiable up to a
cone small set.
Archive classification: math.FA
Mathematics Subject Classification: 46B26, 28A05, 54E35, 58C20
Submitted from: cuthm5am(a)karlin.mff.cuni.cz
The paper may be downloaded from the archive by web browser from URL
http://front.math.ucdavis.edu/1309.2174
or
http://arXiv.org/abs/1309.2174
This is an announcement for the paper "Almost limited sets in Banach
lattices" by Jin Xi Chen, Zi Li Chen, and Guo Xing Ji.
Abstract: We introduce and study the class of almost limited sets in
Banach lattices, that is, sets on which every disjoint weak$^{*}$ null
sequence of functionals converges uniformly to zero. It is established
that a Banach lattice has order continuous norm if and only if almost
limited sets and $L$-weakly compact sets coincide. In particular, in terms
of almost Dunford-Pettis operators into $c_{0}$, we give an operator
characterization of those $\sigma$-Dedekind complete Banach lattices
whose relatively weakly compact sets are almost limited, that is, for a
$\sigma$-Dedekind Banach lattice $E$, every relatively weakly compact
set in $E$ is almost limited if and only if every continuous linear
operator $T:E\rightarrow c_{0}$ is an almost Dunford-Pettis operator.
Archive classification: math.FA
Mathematics Subject Classification: Primary 46B42, Secondary 46B50, 47B65
Remarks: 11 pages
Submitted from: jinxichen(a)home.swjtu.edu.cn
The paper may be downloaded from the archive by web browser from URL
http://front.math.ucdavis.edu/1309.2020
or
http://arXiv.org/abs/1309.2020
This is an announcement for the paper "Integral isoperimetric transference
and dimensionless Sobolev inequalities" by Joaquim Martin and Mario
Milman.
Abstract: We introduce the concept of Gaussian integral isoperimetric
transference and show how it can be applied to obtain a new class of
sharp Sobolev-Poincar\'{e} inequalities with constants independent
of the dimension. In the special case of $L^{q}$ spaces on the unit
$n-$dimensional cube our results extend the recent inequalities that
were obtained in \cite{FKS} using extrapolation.
Archive classification: math.FA
Submitted from: mario.milman(a)gmail.com
The paper may be downloaded from the archive by web browser from URL
http://front.math.ucdavis.edu/1309.1980
or
http://arXiv.org/abs/1309.1980
This is an announcement for the paper "Lineability, spaceability,
and additivity cardinals for Darboux-like functions" by Krzysztof
Chris Ciesielski, Jose L. Gamez-Merino, Daniel Pellegrino, and Juan
B. Seoane-Sepulveda.
Abstract: We introduce the concept of {\em maximal lineability cardinal
number}, $\mL(M)$, of a subset $M$ of a topological vector space and
study its relation to the cardinal numbers known as: additivity $A(M)$,
homogeneous lineability $\HL(M)$, and lineability $\LL(M)$ of $M$. In
particular, we will describe, in terms of $\LL$, the lineability and
spaceability of the families of the following Darboux-like functions on
$\real^n$, $n\ge 1$: extendable, Jones, and almost continuous functions.
Archive classification: math.FA
Submitted from: jseoane(a)mat.ucm.es
The paper may be downloaded from the archive by web browser from URL
http://front.math.ucdavis.edu/1309.1965
or
http://arXiv.org/abs/1309.1965
This is an announcement for the paper "On Borel structures in the Banach
space C(\beta\omega)" by Witold Marciszewski and Grzegorz Plebanek.
Abstract: M. Talagrand showed that, for the Cech-Stone compactification
\beta\omega\ of the space of natural numbers, the norm and the weak
topology generate different Borel structures in the Banach space
C(\beta\omega). We prove that the Borel structures in C(\beta\omega)
generated by the weak and the pointwise topology are also different.
We also show that in C(\omega*), where \omega*=\beta\omega - \omega,
there is no countable family of pointwise Borel sets separating functions
from C(\omega*).
Archive classification: math.FA
Mathematics Subject Classification: 46B26, 46E15, 54C35, 54H05
Remarks: 14 pages
Submitted from: grzes(a)math.uni.wroc.pl
The paper may be downloaded from the archive by web browser from URL
http://front.math.ucdavis.edu/1309.1908
or
http://arXiv.org/abs/1309.1908