Research
On-device research index

arXiv research

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

Trend · papers per month

74148222296 · May 202619922001200920172026
48 results for presheaf construction

In this article we give an equivariant version for the construction of generic models on presheaves of structures. We deal with first order structures endowed with a suitable action of some fixed group, say GG; we call them GG-structures. We show that every exact presheaf of GG-structures M\mathcal{M} has a generic…

2013-04-09abs ↗pdf ↗

Develops a new exponential map for time-varying vector fields.

problem Lack of global flows for general time-varying vector fields.
method Categorical development of spaces of vector fields and flows, allowing for systematic localisation.
result Derives the homeomorphism of the exponential map for vector fields with measurable time-dependence.

We introduce notions such as cdp presheaf, cds precosheaf, Mayer-Vietoris system, and investigate their properties. As applications, we study cohomologies with values in local systems on smooth manifolds and Dolbeault cohomologies with values in locally free sheaves on complex manifolds, where the compactness is not ne…

2018-11-14abs ↗pdf ↗

Detecting exotic spheres involves analyzing framed configuration spaces.

problem Detecting exotic spheres through homotopy type of truncated Disc-presheaves.
method Using gluing results for Disc-presheaves, Atiyah duality, and computations of mapping class groups.
result Conditions for detecting exotic spheres through framed configuration spaces.

In this paper we introduce Bα,βkB_{α,β}^{k}-manifolds as generalizations of the notion of smooth manifolds with GG-structure or with kk-bounded geometry. These are CkC^{k}-manifolds whose transition functions φji=φjφi1\varphi_{ji}=\varphi_{j}\circ\varphi_{i}^{-1} are such that $\partial^μ\varphi_{ji}\in B_{α(r)}\cap C^{k-β(r)}…

2019-08-13abs ↗pdf ↗

An automorphism on a complex supermanifold M\mathcal M is called unipotent if it reduces to the identity on the associated graded supermanifold gr(M)gr(\mathcal M). These automorphisms are close to be complementary to those responsible for homogeneity of a supermanifold. In analogy, their study yields results on the clas…

2016-07-23abs ↗pdf ↗

New method recovers differential cohomology from diffeological spaces.

problem Recovering differential cohomology from diffeological spaces.
method Introducing skeletal diffeologies and thin homotopies to recover differential cohomology.
result Ordinary differential cohomology can be recovered in terms of the homotopy theory of skeletal diffeological spaces.

Article constructs coassociative submanifolds in Joyce's G2G_2-manifolds.

problem Constructing coassociative submanifolds in Joyce's G2G_2-manifolds.
method Using Joyce's generalised Kummer construction, focusing on the critical region where the metric degenerates.
result The volume of the coassociatives shrinks to zero as the orbifold-limit is approached.

The twist construction is a geometric model of T-duality that includes constructions of nilmanifolds from tori. This paper shows how one-dimensional foliations on manifolds may be used in a shear construction, which in algebraic form builds certain solvable Lie groups from Abelian ones. We discuss other examples of geo…

2015-05-31abs ↗pdf ↗

We describe various constructions in Sasakian geometry. First we generalize the join construction of the first two authors to arbitrary Sasakian manifolds. We then give several examples, including ones which prove the existence of Sasakian-Einstein metrics on manifolds homeomorphic to S2×S5.S^2\times S^5. Then we use a gen…

2006-02-10abs ↗pdf ↗

We construct bi-invariant total orderings of residually torsion-free nilpotent groups by using Chen's iterated integrals. This construction can be seen as a generalization of the Magnus ordering of the free groups, and equivalent to the classical construction which uses an iteration of central extensions. Our geometric…

2010-05-21abs ↗pdf ↗

The paper constructs infinitely many surfaces with specific mean curvature.

problem Creating surfaces with prescribed mean curvature in the presence of a strictly stable minimal surface.
method Synthesizing ideas from previous constructions to create multiple surfaces.
result Infinitely many distinct surfaces with prescribed mean curvature are constructed.

We introduce the cutting construction of possibly non-compact symplectic toric manifolds, in particular, toric symplectic cones that correspond to a weakly convex good cone. Since the symplectization of a toric contact manifold is a toric symplectic cone, we can also construct toric contact manifolds that correspond to…

2013-01-13abs ↗pdf ↗

We construct calibrated submanifolds of R^7 and R^8 by viewing them as total spaces of vector bundles and taking appropriate sub-bundles which are naturally defined using certain surfaces in R^4. We construct examples of associative and coassociative submanifolds of R^7 and of Cayley submanifolds of R^8. This construct…

2004-07-31abs ↗pdf ↗

The paper constructs solutions to a critical Dirac equation on spheres.

problem Solving the critical Dirac equation on spheres with singularities.
method Constructing Delaunay-type solutions and another kind of singular solutions.
result The constructed solutions are building blocks for singular solutions on Spin manifolds.

In this paper, we construct the index bundle gerbe of a family of self-adjoint Dirac-type operators, refining a construction of Segal. In a special case, we construct a geometric bundle gerbe called the caloron bundle gerbe, which comes with a natural connection and curving, and show that it is isomorphic to the analyt…

2011-07-19abs ↗pdf ↗

Springer varieties appear in both geometric representation theory and knot theory. Motivated by knot theory and categorification Khovanov provides a topological construction of (n/2,n/2)(n/2, n/2) Springer varieties. We extend Khovanov's construction to all two-row Springer varieties. Using the combinatorial and diagrammatic …

2010-07-05abs ↗pdf ↗

This is the second paper in a series of papers aimed at providing a geometric construction of modular functors and topological quantum field theories from conformal field theory building on the constructions in [TUY] and [KNTY]. We give a geometric construct of a modular functor for any simple Lie-algebra and any level…

2003-06-16abs ↗pdf ↗

We give an algebro-geometric construction of some of the non-arithmetic ball quotients constructed by the author, Parker and Paupert. The new construction reveals a relationship between the corresponding orbifold fundamental groups and the automorphism group of the Klein quartic, and also with groups constructed by Bar…

2016-05-12abs ↗pdf ↗

The article consists of the Russian and English variants of Ph.D. Thesis in which the answers is given on the following questions: 1. how to construct the spinor formalism for n=6; 2. how to construct the spinor formalism for n=8; 3. how to prolong the Riemannian connection from the tangent bundle into the spinor one w…

2012-04-01abs ↗pdf ↗