This is an announcement for the paper "On operator relations between
locally convex spaces" by Ersin Kizgut, Elif Uyanik, and Murat Yurdakul.
Abstract:
A linear operator $T:X \to Y$ between vector spaces is called strictly
singular if for any infinite dimensional closed vector subspace $M$ of
$X$, the restriction of $T$ on $M$ is not a topological isomorphism. In
this note we introduced some sufficient conditions on domain and range
spaces such that any bounded linear operator in between is strictly
singular, and give some examples of spaces satisfying these conditions.
Archive classification: math.FA
Remarks: 15 pages, presented in the context of 8th Australian and New
The paper may be downloaded from the archive by web browser from URL
http://front.math.ucdavis.edu/1412.5761
or
http://arXiv.org/abs/1412.5761
This is an announcement for the paper "On M-ideals and o-O type spaces"
by Karl-Mikael Perfekt.
Abstract:
We consider pairs of Banach spaces (M_0, M) such that M_0 is defined
in terms of a little-o condition, and M is defined by the corresponding
big-O condition. The construction is general and pairs include function
spaces of vanishing and bounded mean oscillation, vanishing weighted and
weighted spaces of functions or their derivatives, M\"obius invariant
spaces of analytic functions, Lipschitz-H\"older spaces, etc. It has
previously been shown that the bidual M_0** of M_0 is isometrically
isomorphic with M. The main result of this paper is that M_0 is an
M-ideal in M. This has several useful consequences: M_0 has Pelczynskis
properties (u) and (V), M_0 is proximinal in M, and M_0* is a strongly
unique predual of M, while M_0 itself never is a strongly unique predual.
Archive classification: math.FA
Remarks: 9 pages
Submitted from: karlmikp(a)math.ntnu.no
The paper may be downloaded from the archive by web browser from URL
http://front.math.ucdavis.edu/1412.5486
or
http://arXiv.org/abs/1412.5486
This is an announcement for the paper "A letter: The log-Brunn-Minkowski
inequality for complex bodies" by Liran Rotem.
Abstract:
In this short note we explain why the log-Brunn-Minkowski conjecture is
correct for complex convex bodies. We do this by relating the conjecture
to the notion of complex interpolation, and appealing to a general
theorem by Cordero-Erausquin.
Archive classification: math.MG math.FA
Submitted from: liranro1(a)post.tau.ac.il
The paper may be downloaded from the archive by web browser from URL
http://front.math.ucdavis.edu/1412.5321
or
http://arXiv.org/abs/1412.5321
This is an announcement for the paper "Almost sure-sign convergence
of Hardy-type Dirichlet series" by Daniel Carando, Andreas Defant,
and Pablo Sevilla-Peris.
Abstract:
Hartman proved in 1939 that the width of the largest possible strip
in the complex plane, on which a Dirichlet series $\sum_n a_n n^{-s}$ is
uniformly a.s.-sign convergent (i.e., $\sum_n \varepsilon_n a_n n^{-s}$
converges uniformly for almost all sequences of signs $\varepsilon_n
=\pm 1$) but does not convergent absolutely, equals $1/2$. We study this
result from a more modern point of view within the framework of so called
Hardy-type Dirichlet series with values in a Banach space.
Archive classification: math.FA
Mathematics Subject Classification: 30B50, 30H10, 46G20
Submitted from: dcarando(a)dm.uba.ar
The paper may be downloaded from the archive by web browser from URL
http://front.math.ucdavis.edu/1412.5030
or
http://arXiv.org/abs/1412.5030
This is an announcement for the paper "Burkholder-Gundy-Davis inequality
in martingale Hardy spaces with variable exponent" by Peide Liu and
Maofa Wang.
Abstract:
In this paper, the classical Dellacherie's theorem about stochastic
process is extended to variable exponent Lebesgue spaces. As its
applications, we obtain variable exponent analogues of several famous
inequalities in classical martingale theory, including convexity lemma,
Burkholder-Gundy-Davis' inequality and Chevalier's inequality. Moreover,
we investigate some other equivalent relations between variable exponent
martingale Hardy spaces.
Archive classification: math.FA
Submitted from: pdliu(a)whu.edu.cn
The paper may be downloaded from the archive by web browser from URL
http://front.math.ucdavis.edu/1412.8146
or
http://arXiv.org/abs/1412.8146
This is an announcement for the paper "Quotients of Banach algebras
acting on $L^p$-spaces" by Eusebio Gardella and Hannes Thiel.
Abstract:
We show that the class of Banach algebras that can be isometrically
represented on an $L^p$-space, for $p\neq 2$, is not closed under
quotients. This answers a question asked by Le Merdy 20 years ago. Our
methods are heavily reliant on our earlier study of Banach algebras
generated by invertible isometries of $L^p$-spaces.
Archive classification: math.OA math.FA
Mathematics Subject Classification: Primary: 47L10, 43A15. Secondary:
46J10
Remarks: 7 pages
Submitted from: gardella(a)uoregon.edu
The paper may be downloaded from the archive by web browser from URL
http://front.math.ucdavis.edu/1412.3985
or
http://arXiv.org/abs/1412.3985
This is an announcement for the paper "On C*-algebras which cannot
be decomposed into tensor products with factors infinite-dimensional"
by Tomasz Kania.
Abstract:
We prove that C*-algebras which satisfy a Banach-space property of
being a Grothendieck space cannot be decomposed into a tensor product
of two infinite-dimensional Banach spaces. By a result of Pfitzner, this
class contains all von Neumann algebras and their norm-quotients. We thus
strengthen a recent result of Ghasemi who established a similar conclusion
for C*-tensor products in the case of SAW*-algebras. In particular, we
solve in the negative a problem of Simon Wassermann concerning tensorial
decompositions of the Calkin algebra in the category of Banach spaces.
Archive classification: math.OA math.FA
Submitted from: tomasz.marcin.kania(a)gmail.com
The paper may be downloaded from the archive by web browser from URL
http://front.math.ucdavis.edu/1412.3621
or
http://arXiv.org/abs/1412.3621
This is an announcement for the paper "H\"{o}lder's inequality: some
recent and unexpected applications" by N. Albuquerque, G. Araujo, and
D. Pellegrino.
Abstract:
H\"{o}lder's inequality, since its appearance in 1888, has played a
fundamental role in Mathematical Analysis and it is, without any
doubt, one of the milestones in Mathematics. It may seem strange
that, nowadays, it keeps resurfacing and bringing new insights to the
mathematical community. In this expository article we show how a variant
of H\"{o}lder's inequality (although well-known in PDEs) was essentially
overlooked in Functional Analysis and has had a crucial (and in some
sense unexpected) influence in very recent and major breakthroughs
in Mathematics. Some of these recent advances appeared in 2012-2014
and include the theory of Dirichlet series, the famous Bohr radius
problem, certain classical inequalities (such as Bohnenblust--Hille or
Hardy--Littlewood), or even Mathematical Physics.
Archive classification: math.FA
Submitted from: pellegrino(a)pq.cnpq.br
The paper may be downloaded from the archive by web browser from URL
http://front.math.ucdavis.edu/1412.2017
or
http://arXiv.org/abs/1412.2017
This is an announcement for the paper "Networks for the weak topology
of Banach and Frechet spaces" by S. Gabriyelyan, J. Kcakol, W. Kubis,
and W. Marciszewski.
Abstract:
We start the systematic study of Fr\'{e}chet spaces which are
$\aleph$-spaces in the weak topology. A topological space $X$ is an
$\aleph_0$-space or an $\aleph$-space if $X$ has a countable $k$-network
or a $\sigma$-locally finite $k$-network, respectively. We are motivated
by the following result of Corson (1966): If the space $C_{c}(X)$
of continuous real-valued functions on a Tychonoff space $X$ endowed
with the compact-open topology is a Banach space, then $C_{c}(X)$
endowed with the weak topology is an $\aleph_0$-space if and only if
$X$ is countable. We extend Corson's result as follows: If the space
$E:=C_{c}(X)$ is a Fr\'echet lcs, then $E$ endowed with its weak topology
$\sigma(E,E')$ is an $\aleph$-space if and only if $(E,\sigma(E,E'))$
is an $\aleph_0$-space if and only if $X$ is countable. We obtain a
necessary and some sufficient conditions on a Fr\'echet lcs to be an
$\aleph$-space in the weak topology. We prove that a reflexive Fr\'echet
lcs $E$ in the weak topology $\sigma(E,E')$ is an $\aleph$-space if
and only if $(E,\sigma(E,E'))$ is an $\aleph_0$-space if and only if
$E$ is separable. We show however that the nonseparable Banach space
$\ell_{1}(\mathbb{R})$ with the weak topology is an $\aleph$-space.
Archive classification: math.FA
Mathematics Subject Classification: Primary 46A03, 54H11, Secondary
22A05, 54C35
Remarks: 18 pages
Submitted from: kubis(a)math.cas.cz
The paper may be downloaded from the archive by web browser from URL
http://front.math.ucdavis.edu/1412.1748
or
http://arXiv.org/abs/1412.1748
This is an announcement for the paper "A note on dependence of families
having bounded variation" by Michael Megrelishvili.
Abstract:
We show that for arbitrary linearly ordered set $X$ any bounded
family of real valued functions on $X$ with bounded total variation
does not contain independent subsequences. As a corollary we generalize
Helly's sequential compactness theorem.
Archive classification: math.GN math.FA
Mathematics Subject Classification: 54F15, 54D30, 06A05
Remarks: 7 pages
Submitted from: megereli(a)math.biu.ac.il
The paper may be downloaded from the archive by web browser from URL
http://front.math.ucdavis.edu/1412.1515
or
http://arXiv.org/abs/1412.1515