Results 61 to 70 of about 514 (184)

Undecidability of polynomial inequalities in weighted graph homomorphism densities

open access: yesForum of Mathematics, Sigma
Many problems and conjectures in extremal combinatorics concern polynomial inequalities between homomorphism densities of graphs where we allow edges to have real weights.
Grigoriy Blekherman   +2 more
doaj   +1 more source

On computing local monodromy and the numerical local irreducible decomposition

open access: yesTransactions of the London Mathematical Society, Volume 13, Issue 1, December 2026.
Abstract Similarly to the global case, the local structure of a holomorphic subvariety at a given point is described by its local irreducible decomposition. Geometrically, the key requirement for obtaining a local irreducible decomposition is to compute the local monodromy action of a generic linear projection at the given point, which is always well ...
Parker B. Edwards   +1 more
wiley   +1 more source

On the additive image of zeroth persistent homology

open access: yesTransactions of the London Mathematical Society, Volume 13, Issue 1, December 2026.
Abstract For a category X$X$ and a finite field F$F$, we study the additive image of the functor H0(−;F)∗:rep(X,Top)→rep(X,VectF)$\operatorname{H}_0(-;F)_* \colon \operatorname{rep}(X, \mathbf {Top}) \rightarrow \operatorname{rep}(X, \mathbf {Vect}_F)$, or equivalently, of the free functor rep(X,Set)→rep(X,VectF)$\operatorname{rep}(X, \mathbf {Set ...
Ulrich Bauer   +3 more
wiley   +1 more source

Homomorphisms of derivative graphs

open access: yesDiscrete Mathematics, 1971
AbstractThe derivative graphs and their homomorphisms are studied. Inspirated by the Whitney theorem on automorphisms, we are considering endomorphisms of a graph in their relationship to endomorphisms of its derivative graph. Particularly, we characterize in this connection the graphs with the best endomorphisms.
openaire   +1 more source

Homomorphisms of strongly regular graphs [PDF]

open access: yesAlgebraic Combinatorics, 2016
We prove that if G and H are primitive strongly regular graphs with the same parameters and φ
openaire   +3 more sources

Context‐free graphs and their transition groups

open access: yesTransactions of the London Mathematical Society, Volume 13, Issue 1, December 2026.
Abstract Starting from context‐free inverse graphs, we introduce a new class of groups and study their structural properties. We establish closure properties, show that their coword problems are context‐free, analyze torsion elements, and realize them as subgroups of the asynchronous rational group.
Daniele D'Angeli   +3 more
wiley   +1 more source

The dynamics of non-perturbative phases via Banach bundles

open access: yesNuclear Physics B, 2021
Strongly coupled Dyson–Schwinger equations generate infinite power series of running coupling constants together with Feynman diagrams with increasing loop orders as coefficients. Theory of graphons for sparse graphs can address a new useful approach for
Ali Shojaei-Fard
doaj   +1 more source

Signed Projective Cubes, a Homomorphism Point of View

open access: yesJournal of Graph Theory, Volume 113, Issue 1, Page 38-56, September 2026.
ABSTRACT The (signed) projective cubes, as a special class of graphs closely related to the hypercubes, are on the crossroad of geometry, algebra, discrete mathematics and linear algebra. Defined as Cayley graphs on binary groups, they represent basic linear dependencies.
Meirun Chen   +2 more
wiley   +1 more source

Free semigroups of large critical exponent

open access: yesJournal of Topology, Volume 19, Issue 3, September 2026.
Abstract For a convergence group equipped with an expanding coarse‐cocycle, we construct finitely generated free subsemigroups, which we call Bishop−−Jonessemigroups$\textit{Bishop--Jones semigroups}$, of critical exponent arbitrarily close to but strictly less than the critical exponent of the ambient group.
Aleksander Skenderi
wiley   +1 more source

Surface subgroups for cocompact lattices of isometries of H2n$\mathbb {H}^{2n}$

open access: yesJournal of Topology, Volume 19, Issue 3, September 2026.
Abstract We prove the existence of surface subgroups within any cocompact lattice Γ$\Gamma$ in SO(2n,1)$\mathrm{SO}(2n,1)$ for n⩾2$n\geqslant 2$. This result addresses the cases missing from the work of Hamenstädt in 2015, who constructed surface subgroups in cocompact lattices for all other rank‐1 simple Lie groups of noncompact type.
Jeremy Kahn, Zhenghao Rao
wiley   +1 more source

Home - About - Disclaimer - Privacy