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Related papers: Euler characteristic on noncommutative polyballs

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We develop a dilation theory for row contractions subject to constraints determined by sets of noncommutative polynomials. Under natural conditions on the constraints, we have uniqueness for the minimal dilation. A characteristic function…

Operator Algebras · Mathematics 2007-05-23 Gelu Popescu

We write the Euler characteristic X(G) of a four dimensional finite simple geometric graph G=(V,E) in terms of the Euler characteristic X(G(w)) of two-dimensional geometric subgraphs G(w). The Euler curvature K(x) of a four dimensional…

Geometric Topology · Mathematics 2013-07-16 Oliver Knill

We show that a Beurling type theory of invariant subspaces of noncommutative $H^2$ spaces holds true in the setting of subdiagonal subalgebras of $\sigma$-finite von Neumann algebras. This extends earlier work of Blecher and Labuschagne for…

Operator Algebras · Mathematics 2017-05-04 Louis Labuschagne

We make explicit computations in the formal symplectic geometry of Kontsevich and determine the Euler characteristics of the three cases, namely commutative, Lie and associative ones, up to certain weights.From these, we obtain some…

Algebraic Topology · Mathematics 2015-04-14 Shigeyuki Morita , Takuya Sakasai , Masaaki Suzuki

For any acyclic quiver $Q$ without multiple edges, we construct a monoidal category $\mathcal{R}_Q$ whose indecomposable objects are tensor products (over the base field) of finite-dimensional modules over the path algebra of $Q$. We show…

Representation Theory · Mathematics 2026-05-28 Élie Casbi

We express characteristic numbers of compact hyperk\"ahler manifolds in graph-theoretical form, considering them as a special case of the curvature invariants introduced by Rozansky and Witten. The appropriate graphs are generated by…

Differential Geometry · Mathematics 2007-05-23 Nigel Hitchin , Justin Sawon

We show that integration with respect to the Euler-Poincar\'e characteristic can be extended from the setting of definable sets to the setting of topological spaces homeomorphic to definable sets. We use that extension to generalize a…

Algebraic Topology · Mathematics 2018-07-05 E. Macías-Virgós , D. Mosquera-Lois

For a finitely presented discrete group $\Gamma$, we introduce two generalizations of the orbifold Euler characteristic and $\Gamma$-orbifold Euler characteristic to a class of proper topological groupoids large enough to include all…

Algebraic Topology · Mathematics 2022-10-19 Carla Farsi , Christopher Seaton

We consider closed manifolds that admit a metric locally isometric to a product of symmetric planes. For such manifolds, we prove that the Euler characteristic is an obstruction to the existence of flat structures, confirming an old…

Geometric Topology · Mathematics 2009-05-23 Michelle Bucher , Tsachik Gelander

We consider the Euler characteristics $\chi(M)$ of closed orientable topological $2n$-manifolds with $(n-1)$-connected universal cover and a given fundamental group $G$ of type $F_n$. We define $q_{2n}(G)$, a generalized version of the…

Geometric Topology · Mathematics 2023-02-27 Alejandro Adem , Ian Hambleton

It is well known that the Euler characteristic of an odd dimensional compact manifold is zero. An Euler complex is a combinatorial analogue of a compact manifold. We present here an elementary proof of the corresponding result for Euler…

Geometric Topology · Mathematics 2013-02-25 Colin MacLaurin , Guyan Robertson

The Euler characteristic is an invariant of a topological space that in a precise sense captures its canonical notion of size, akin to the cardinality of a set. The Euler characteristic is closely related to the homology of a space, as it…

Algebraic Topology · Mathematics 2022-06-22 Nina Otter

We use a classification result of Chenevier and Lannes for algebraic automorphic representations together with a conjectural correspondence with $\ell$-adic absolute Galois representations to determine the Euler characteristics (with values…

Algebraic Geometry · Mathematics 2026-05-27 Jonas Bergström , Carel Faber

We study constructible invariants of the moduli space $\overline{\mathcal{M}}(\boldsymbol{x})$ of stable maps from genus zero curves to $\mathbb{P}^1$, relative to $0$ and $\infty$, with ramification profiles specified by…

Algebraic Geometry · Mathematics 2022-03-08 Siddarth Kannan

We prove a formula for the ${\mathbb S}_n$-equivariant Euler characteristic of the moduli space of graphs $\mathcal{MG}_{g,n}$. Moreover, we prove that the rational ${\mathbb S}_n$-invariant cohomology of $\mathcal{MG}_{g,n}$ stabilizes for…

Algebraic Topology · Mathematics 2025-11-05 Michael Borinsky , Jos Vermaseren

Let $E$ be the bundle defined by applying a polynomial representation of $GL_n$ to the tautological bundle on the Hilbert scheme of $n$ points in the complex plane. By a result of Haiman, the Cech cohomology groups $H^i(E)$ vanish for all…

Representation Theory · Mathematics 2013-01-01 Erik Carlsson

We make calculations in graph homology which further understanding of the topology of spaces of string links, in particular calculating the Euler characteristics of finite-dimensional summands in their homology and homotopy. In doing so, we…

Algebraic Topology · Mathematics 2018-01-09 Paul Arnaud Songhafouo Tsopméné , Victor Turchin

We study the Euler characteristic of a hypersurface in $(\mathbb{C}^*)^2 \times (\mathbb{C}^*)^n$ defined by a polynomial whose monomial support corresponds to lattice points in $\Delta_1 \times \Delta_1 \times \Delta_n$ as the coefficients…

Algebraic Geometry · Mathematics 2026-04-28 Serkan Hoşten , Vadym Kurylenko , Elke Neuhaus , Nikolas Rieke

We relate certain universal curvature identities for Kaehler manifolds to the Euler-Lagrange equations of the scalar invariants which are defined by pairing characteristic forms with powers of the Kaehler form.

Differential Geometry · Mathematics 2013-11-13 P. Gilkey , J. H. Park , K. Sekigawa

We discuss the universal orbifold Euler characteristic and generalized orbifold Euler characteristics corresponding to finitely generated groups $A$ (the $A$-Euler characteristics). We show that the collection of all $A$-Euler…

Algebraic Geometry · Mathematics 2024-05-15 Sabir M. Gusein-Zade , Ignacio Luengo , Alejandro Melle-Hernández , Antonio Viruel