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A locally-built, LLM-digested index of recent arXiv papers in quant finance, geometry/topology, and statistical ML — keyword search served straight from SQLite on this machine.

168,742 papers · 148 categories

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11233445 · Jul 202519922001200920172026
48 results for cohomological isomorphism

The equivariant cohomology of a space with a group action is not only a ring but also an algebra over the cohomology ring of the classifying space of the acting group. We prove that toric manifolds (i.e. compact smooth toric varieties) are isomorphic as varieties if and only if their equivariant cohomology algebras are…

2007-03-12abs ↗pdf ↗

Suppose G is a compact Lie group and N is a closed normal subgroup of G acting freely on a smooth manifold X. The Cartan theorem alluded to in the title postulates the existence of a natural isomorphism between the G-equivariant cohomology X and the G/N-equivariant cohomology of X/N. In this note we use J. Kalkman's ex…

2000-05-07abs ↗pdf ↗

New proof for 4D symplectic manifolds: equivariant cohomology determines diffeotype.

problem Determining if 4D symplectic manifolds are diffeomorphic based on their equivariant cohomology.
method Proved that equivariant cohomology rings of Hamiltonian circle actions on 4D symplectic manifolds determine their equivariant diffeotypes.
result Isomorphism of equivariant cohomology rings implies equivariant diffeomorphism for 4D symplectic manifolds.

`Loop-fusion cohomology' is defined on the continuous loop space of a manifold in terms of \vCech cochains satisfying two multiplicative conditions with respect to the fusion and figure-of-eight products on loops. The main result is that these cohomology groups, with coefficients in an abelian group, are isomorphic to …

2013-09-29abs ↗pdf ↗

Let M be a Poisson manifold and A a Weil algebra. We describe an isomorphism of cohomolgy algebra and proves that Poisson cohomology with values in A is isomorphic to the tensor product of A with Poisson cohomolgy with real values.

2015-09-09abs ↗pdf ↗

Let GG be a simply connected solvable Lie group with a lattice ΓΓ and the Lie algebra $\g$ and a representation ρ:GGL(Vρ)ρ:G\to GL(V_ρ) whose restriction on the nilradical is unipotent. Consider the flat bundle EρE_ρ given by ρρ. By using "many" characters {α}\{α\} of GG and "many" flat line bundles {Eα}\{E_α\} over G/ΓG/Γ, w…

2012-07-17abs ↗pdf ↗

It is proved that on nilmanifolds with abelian complex structure, there exists a canonically constructed non-trivial holomorphic Poisson structure. We identify the necessary and sufficient condition for its associated cohomology to be isomorphic to the cohomology associated to trivial (zero) holomorphic Poisson structu…

2018-09-11abs ↗pdf ↗

The paper constructs discrete Hessian and divdiv complexes on triangulations and proves their cohomology isomorphic to continuous versions.

problem Discrete construction of Hessian and divdiv complexes on triangulations.
method Construction of discrete Hessian and divdiv complexes using finite elements and Dirac measures on triangulations.
result The cohomology of the constructed complexes is isomorphic to the continuous de Rham cohomology.

For a simply connected (non-nilpotent) solvable Lie group GG with a lattice ΓΓ the de Rham and Dolbeault cohomologies of the solvmanifold G/ΓG/Γ are not in general isomorphic to the cohomologies of the Lie algebra g\mathfrak g of GG. In this paper we construct, up to a finite group, a new Lie algebra $\tilde{\mathfr…

2013-01-25abs ↗pdf ↗

Paper constructs Chern character for higher twists and shows isomorphism between K-theory and cohomology.

problem Mapping higher twisted K-theory to higher twisted cohomology.
method Constructing Chern character for higher twists and showing isomorphism.
result Chern character gives isomorphism between higher twisted K-theory and higher twisted cohomology.

Cohomological and homological spectral sequences are shown to be isomorphic.

problem Cohomological and homological Atiyah-Hirzebruch spectral sequences are not always isomorphic.
method Spanier-Whitehead duality is used to establish an isomorphism between the two spectral sequences.
result Cohomological and homological Atiyah-Hirzebruch spectral sequences are isomorphic for finite spectra.

Paper shows 3D hyperbolic manifolds are uniquely identified by their finite groups.

problem Identifying hyperbolic 3-manifolds using their finite quotient groups.
method Proves profinite isomorphism of fundamental groups uniquely determines the manifold's isomorphism type.
result Finite-volume hyperbolic 3-manifolds are almost determined by their finite quotient groups.

Let G be a compact, connected Lie group, acting smoothly on a manifold M. Goresky-Kottwitz-MacPherson described a small Cartan model for the equivariant cohomology of M, quasi-isomorphic to the standard Cartan complex of equivariant differential forms. In this paper, we construct an explicit cochain map from the small …

2004-06-17abs ↗pdf ↗

We generalize Lagrangian Floer cohomology to sequences of Lagrangian correspondences. For sequences related by the geometric composition of Lagrangian correspondences we establish an isomorphism of the Floer cohomologies. We give applications to calculations of Floer cohomology, displaceability of Lagrangian correspond…

2009-05-09abs ↗pdf ↗

We review the notion of relative Dolbeault cohomology and prove that it is canonically isomorphic with the local (relative) cohomology of A. Grothendieck and M. Sato with coefficients in the sheaf of holomorphic forms. We deal with this cohomology from two viewpoints. One is the Cech theoretical approach, which is conv…

2019-03-12abs ↗pdf ↗

If M is a riemannian manifold, then the inclusion of the complex of coclosed harmonic forms into the de Rham complex induces a linear isomorphism in cohomology. If M has at most countably many connected components, this linear isomorphism is a Frechet isomorphism.

2000-03-05abs ↗pdf ↗

We show that the de Rham theorem, interpreted as the isomorphism between distributional de Rham cohomology and simplicial homology in the dual dimension for a simplicial decomposition of a compact oriented manifold, is a straightforward consequence of elementary properties of currents. The explicit construction of this…

2011-05-13abs ↗pdf ↗

Main theorem of this paper states that Floer cohomology groups in a Hilbert space are isomorphic to the cohomological Conley Index. It is also shown that calculating cohomological Conley Index does not require finite dimensional approximations of the vector field. Further directions are discussed.

2014-01-30abs ↗pdf ↗

We give a proof of a Conjecture of Walker which states that one can recover the lengths of the bars of a circular linkage from the cohomology ring of the configuration space. For a large class of length vectors, this has been shown by Farber, Hausmann and Schuetz. In the remaining cases, we use Morse theory and the fun…

2009-06-24abs ↗pdf ↗

For an orbifold X and αH3(X,Z)α\in H^3(X, Z), we introduce the twisted cohomology Hc(X,α)H^*_c(X, α) and prove that the Connes-Chern character establishes an isomorphism between the twisted K-groups Kα(X)CK_α^* (X) \otimes C and twisted cohomology Hc(X,α)H^*_c(X, α). This theorem, on the one hand, generalizes a classical result of Baum-Co…

2005-05-12abs ↗pdf ↗

Generalizes integration map to coinvariants of bounded functions.

problem Integration map definition and isomorphism proof for coinvariants.
method Generalizes integration map definition to coinvariants of bounded functions, considering relative bounded de Rham cohomology in presence of boundary.
result Integration map is an isomorphism in top-degree bounded de Rham cohomology.

Generalizes Molino's theory for Riemannian foliations.

problem Studying Riemannian foliations and their properties.
method Generalization of Molino's theory with discussion of projections and equivariant basic Â-genus characters.
result Equivariant basic cohomological isomorphism for Killing foliation.

The study explores cohomological invariants and decomposes them into irreducible parts, focusing on zigzags.

problem Finding cohomological invariants and their decomposition into irreducible parts.
method Investigates various cohomological invariants on double complexes, focusing on the multiplicities of zigzags.
result The multiplicities of zigzags in double complexes are not sufficient to distinguish non-isomorphic double complexes.

Let (M,F)(M,\mathcal{F}) be a foliated manifold. We prove that there is a canonical isomorphism between the complex of base-like forms Ωb(M,F)Ω^*_b(M,\mathcal{F}) of the foliation and the "De Rham complex" of the space of leaves M/FM/\mathcal{F} when considered as a "diffeological" quotient. Consequently, the two corresponding …

2009-03-16abs ↗pdf ↗

The study connects hypergraphs to strong homotopy Lie algebras.

problem Characterizing hypergraphs with a system of distinct representatives.
method Describing a procedure to attach nilpotent strong homotopy Lie algebras to hypergraphs.
result Isomorphic hypergraphs correspond to isomorphic strong homotopy Lie algebras.

Generalizes cohomology ring result for combinatorial line arrangements.

problem Cohomology ring of boundary manifold for combinatorial line arrangements.
method Introduced boundary manifold, constructed homology cycles, computed cohomology ring.
result Cohomology ring of boundary manifold is isomorphic to double of Orlik-Solomon algebra.

Study Hochschild cohomology of dg manifolds linked to integrable distributions.

problem Understanding Hochschild cohomology of dg manifolds associated with integrable distributions.
method Analyzing the Hochschild cohomology of (F[1],dF)(F[1],d_F) and relating it to the algebra of functions on leaf space.
result Established a canonical isomorphism between the Hochschild cohomology of (F[1],dF)(F[1],d_F) and the algebra of functions on leaf space.

Let V be a holomorphic bundle over a complex manifold M, and s be a holomorphic section of V. We study different types of cohomology associated to the Koszul complex induced by s. When M is complete, these cohomologies are isomorphic to each other and have self duality.

2018-04-25abs ↗pdf ↗

We construct several infinite families of nonnegatively curved manifolds of low cohomogeneity and small dimension which can be distinguished by their cohomology rings. In particular, we exhibit an infinite family of eight-dimensional cohomogeneity one manifolds of nonnegative curvature with pairwise non-isomorphic comp…

2015-03-28abs ↗pdf ↗

Inspired by the recent works of S. Rao--S. Yang--X.-D. Yang and L. Meng on the blow-up formulae for de Rham and Morse--Novikov cohomology groups, we give a new simple proof of the blow-up formula for Morse--Novikov cohomology by introducing the relative Morse--Novikov cohomology group via sheaf cohomology theory and pr…

2019-07-31abs ↗pdf ↗

Let X be a topological space, and let C(X) be the complex of singular cochains on X with real coefficients. We denote by Cc(X) the subcomplex given by continuous cochains, i.e. by such cochains whose restriction to the space of simplices (endowed with the compact-open topology) defines a continuous real function. We pr…

2009-03-25abs ↗pdf ↗

In this paper we define a new cohomology of a smooth manifold called Lichnerowicz type cohomology attached to a function. Firstly, we study some basic properties of this cohomology as: a de Rham type isomorphism, dependence on the function, singular forms, relative cohomology, Mayer-Vietoris sequence, homotopy invarian…

2012-05-04abs ↗pdf ↗

The paper generalizes Hodge theory to semisimple local systems and proves a geometric Decomposition theorem.

problem Generalizing Hodge theory to semisimple local systems.
method Establishing a canonical isomorphism and proving a global invariant cycle theorem.
result A new geometric proof of the Decomposition theorem for semisimple local systems.

We show that the theory of Lie algebra cohomology can be recast in a topological setting and that classical results, such as the Shapiro lemma and the van Est isomorphism, carry over to this augmented context.

2016-03-11abs ↗pdf ↗