Zobrazeno 1 - 10
of 230
pro vyhledávání: '"Kania, Tomasz"'
Autor:
Kania, Tomasz, Kostana, Ziemowit
Ancel, Dobrowolski, and Grabowski (Studia Math., 1994) proved that every countable discrete subgroup of the additive group of a normed space is free Abelian, hence isomorphic to the direct sum of a certain number of copies of the additive group of th
Externí odkaz:
http://arxiv.org/abs/2408.03226
Autor:
Kania, Tomasz, Maślany, Natalia
We identify a class of smooth Banach *-algebras that are differential subalgebras of commutative C*-algebras whose openness of multiplication is completely determined by the topological stable rank of the target C*-algebra. We then show that group al
Externí odkaz:
http://arxiv.org/abs/2301.02320
Autor:
Balcerzak, Marek, Kania, Tomasz
Let $\mathcal C$ be a concrete category. We prove that if $\mathcal{C}$ admits a universally free object $\mathsf F$, then there is a projectively universal morphism $u\colon \mathsf F\to \mathsf F$, i.e., a morphism $u$ such that for any $B\in \math
Externí odkaz:
http://arxiv.org/abs/2208.03579
We prove that the coordinate functionals associated with filter bases in Banach spaces are continuous as long as the underlying filter is analytic. This removes the large-cardinal hypothesis from the result established by the two last-named authors (
Externí odkaz:
http://arxiv.org/abs/2203.15123
Autor:
Kania, Tomasz, Lewicki, Grzegorz
Isbell and Semadeni [Trans. Amer. Math. Soc. 107 (1963)] proved that every infinite-dimensional $1$-injective Banach space contains a hyperplane that is $(2+\varepsilon)$-injective for every $\varepsilon > 0$, yet is is \emph{not} $2$-injective and r
Externí odkaz:
http://arxiv.org/abs/2201.07837
Autor:
Kania, Tomasz, Lechner, Richard
Stopping-time Banach spaces is a collective term for the class of spaces of eventually null integrable processes that are defined in terms of the behaviour of the stopping times with respect to some fixed filtration. From the point of view of Banach
Externí odkaz:
http://arxiv.org/abs/2112.12534
The present paper contributes to the ongoing programme of quantification of isomorphic Banach space theory focusing on Pe{\l}czy\'nski's classical work on dual Banach spaces containing $L_{1}$ ($=L_{1}[0,1]$) and the Hagler--Stegall characterisation
Externí odkaz:
http://arxiv.org/abs/2108.03057
We investigate possible quantifications of R. C. James' classical work on bases and reflexivity of Banach spaces. By introducing new quantities measuring how far a basic sequence is from being shrinking and/or boundedly complete, we prove quantitativ
Externí odkaz:
http://arxiv.org/abs/2104.06497
Autor:
González, Manuel, Kania, Tomasz
In 1973, Diestel published his seminal paper `Grothendieck spaces and vector measures' that drew a connection between Grothendieck spaces (Banach spaces for which weak- and weak*-sequential convergences in the dual space coincide) and vector measures
Externí odkaz:
http://arxiv.org/abs/2102.03838
A Banach space $X$ has \textit{property $(K)$}, whenever every weak* null sequence in the dual space admits a convex block subsequence $(f_{n})_{n=1}^\infty$ so that $\langle f_{n},x_{n}\rangle\to 0$ as $n\to \infty$ for every weakly null sequence $(
Externí odkaz:
http://arxiv.org/abs/2102.00857