Lupa

Iskanje po repozitoriju Pomoč

A- | A+ | Natisni
Iskalni niz: išči po
išči po
išči po
išči po
* po starem in bolonjskem študiju

Opcije:
  Ponastavi


1 - 10 / 121
Na začetekNa prejšnjo stran12345678910Na naslednjo stranNa konec
1.
2.
Commuting graphs and extremal centralizers
Gregor Dolinar, Aleksandr Èmilevič Guterman, Bojan Kuzma, Polona Oblak, 2014, izvirni znanstveni članek

Opis: We determine the conditions for matrix centralizers which can guarantee the connectedness of the commuting graph for the full matrix algebra ▫$M_n(\mathbb{F})$▫ over an arbitrary field ▫$\mathbb{F}$▫. It is known that if ▫$\mathbb{F}$▫ is an algebraically closed field and ▫$n \ge 3$▫, then the diameter of the commuting graph of ▫$M_n(\mathbb{F})$▫ is always equal to four. We construct a concrete example showing that if ▫$\mathbb{F}$▫ is not algebraically closed, then the commuting graph of ▫$M_n(\mathbb{F})$▫ can be connected with the diameter at least five.
Ključne besede: commuting graph, matrix ring, centralizer
Objavljeno v RUP: 31.12.2021; Ogledov: 930; Prenosov: 23
.pdf Celotno besedilo (228,78 KB)

3.
A note on homomorphisms of matrix semigroup
Matjaž Omladič, Bojan Kuzma, 2013, izvirni znanstveni članek

Opis: Let ▫$\mathbb{F}$▫ be a field. We classify multiplicative maps from ▫${\mathcal M}_n(\mathbb{F})$▫ to ▫${\mathcal M}_{n \choose k}(\mathbb{F})$▫ which annihilate a zero matrix and map rank-▫$k$▫ matrix into a rank-one matrix.
Ključne besede: matrix semigroup, homomorphism, representation
Objavljeno v RUP: 31.12.2021; Ogledov: 895; Prenosov: 18
.pdf Celotno besedilo (247,09 KB)

4.
5.
6.
7.
Mappings that preserve pairs of operators with zero triple Jordan product
Mirko Dobovišek, Bojan Kuzma, Gorazd Lešnjak, Chi-Kwong Li, Tatjana Petek, 2007, izvirni znanstveni članek

Opis: Let ▫$\mathbb{F}$▫ be a field and ▫$n \ge 3$▫. Suppose ▫${\mathfrak{G_1,G_2}} \subseteq M_n(\mathbb{F})▫$ contain all rank-one idempotents. The structure of surjections ▫$\phi : \mathfrak{G_1} \to \mathfrak{G_2}$▫ satisfying ▫$ABA = 0 \iff \phi(A)\phi(B)\phi(A) = 0$▫ is determined. Similar results are also obtained for (a) subsets of bounded operators acting on a complex or real Banach space, (b) the space of Hermitian matrices acting on ▫$n$▫-dimensional vectors over a skew-field, (c) subsets of self-adjoint bounded linear operators acting on an infinite dimensional complex Hilbert space. It is then illustrated that the results can be applied to characterize mappings ▫$\phi$▫ on matrices or operators such that ▫$F(ABA) = F(\phi(A)\phi(B)\phi(A))▫$ for all ▫$A,B$▫ for functions ▫$F$▫ such as the spectral norm, Schatten ▫$p$▫-norm, numerical radius and numerical range, etc.
Ključne besede: matrix algebra, Jordan triple product, nonlinear preservers
Objavljeno v RUP: 03.04.2017; Ogledov: 2555; Prenosov: 98
URL Povezava na celotno besedilo

8.
General preservers of quasi-commutativity on hermitian matrices
Gregor Dolinar, Bojan Kuzma, 2008, izvirni znanstveni članek

Opis: Let ▫$H_n$▫ be the set of all ▫$n \times n$▫ hermitian matrices over ▫$\mathbb{C}$▫, ▫$n \ge 3$▫. It is said that ▫$A,B \in H_n$▫ quasi-commute if there exists a nonzero ▫$\xi \in \mathbb{C}$▫ such that ▫$AB = \xi BA$▫ Bijective not necessarily linear maps on hermitian matrices which preserve quasi-commutativity in both directions are classified.
Ključne besede: mathematics, linear algebra, general preserver, hermitian matrices, quasi-commutativity
Objavljeno v RUP: 03.04.2017; Ogledov: 2310; Prenosov: 256
URL Povezava na celotno besedilo

9.
Bar´ery Gibsona dlja problemy Polia
Gregor Dolinar, Aleksandr Èmilevič Guterman, Bojan Kuzma, 2010, objavljeni znanstveni prispevek na konferenci

Opis: V članku je obravnavana spodnja meja za število neničelnih elementov v ▫$(0, 1)$▫ matrikah, pri katerem se da permanento vedno pretvoriti v determinanto samo s spreminjanjem predznaka ▫$pm$▫ elementom matrike.
Ključne besede: matematika, linearna algebra, teorija matrik, permanenta, determinanta
Objavljeno v RUP: 03.04.2017; Ogledov: 2211; Prenosov: 64
URL Povezava na celotno besedilo

10.
Reflexivity defect of spaces of linear operators
Janko Bračič, Bojan Kuzma, 2009, izvirni znanstveni članek

Opis: For a finite-dimensional linear subspace ▫{$\mathscr{S}} \subseteq {\mathscr{L}} (V,W)$▫ and a positive integer ▫$k$▫, the ▫$k$▫-reflexivity defect of ▫$\mathscr{S}$▫ is defined by ▫${\mathrm{rd}}_k ({\mathscr{S}}) = \dim({\mathrm{Ref}}_k (\mathscr{S})/\mathscr{S})$▫ where ▫${\mathrm{Ref}}_k$▫ is the ▫$k$▫-reflexive closure of ▫$\mathscr{S}$▫. We study this quantity for two-dimensional spaces of operators and for single generated algebras and their commutants.
Ključne besede: mathematics, operator theory, reflexivity defect, reflexivity, two-dimensional space of operators, single generated algebra, commutant
Objavljeno v RUP: 03.04.2017; Ogledov: 2290; Prenosov: 193
URL Povezava na celotno besedilo

Iskanje izvedeno v 0.14 sek.
Na vrh
Logotipi partnerjev Univerza v Mariboru Univerza v Ljubljani Univerza na Primorskem Univerza v Novi Gorici