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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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65130195260 · May 202619922001200920172026
48 results for Fredholm theory

The paper calculates indices for families of Fredholm operators and their extensions.

problem Calculating indices for families of Fredholm operators and their extensions.
method Passing from a Fredholm operator to its graph, deforming the horizontal subspace.
result Index formulas for families of Fredholm realizations and self-adjoint extensions.

We describe a (nonlinear) Fredholm theory for a new class of ambient spaces, as well as for a certain type of categories. The theory is illustrated by an application to the category of stable maps.

2014-12-13abs ↗pdf ↗

This is the revised version of the second paper in a series introducing a generalized Fredholm theory in a new class of smooth spaces called polyfolds. The theory will be illustrated in upcoming papers by applications to Floer Theory, Gromov-Witten Theory and Symplectic Field Theory. Some proofs have been improved and …

2007-05-09abs ↗pdf ↗

The spectral flow theorem is applied to operators on finite intervals.

problem Operators on finite intervals without boundary conditions are not Fredholm.
method Interpolation theory is used to define boundary conditions making the operators Fredholm. The spectral flow theorem is applied to find the Fredholm index.
result The Fredholm index is given by the spectral flow of the operator path.

The main topic is the development of a Fredholm theory in a new class of spaces called M-polyfolds. In the subsequent Volume II the theory will be generalized to an even larger class of spaces called polyfolds, which can also incorporate local symmetries. The whole package provides a functional analytic framework to de…

2014-07-11abs ↗pdf ↗

The abstract extends deformation and tangent groupoid constructions to infinite-dimensional manifolds.

problem Deformation and tangent groupoid constructions for infinite-dimensional manifolds.
method Extending finite-dimensional constructions to Banach and Fredholm manifolds.
result Induced generalized filtrations of tangent bundles and groupoids.

This article provides a version of scale calculus geared towards a notion of (nonlinear) Fredholm maps between certain types of Frechet spaces, retaining as many as possible of the properties Fredholm maps between Banach spaces enjoy, and the existence of a constant rank theorem for such maps. It does so by extending t…

2016-02-23abs ↗pdf ↗

We explain the topology of the space, so called, Fredholm-Lagrangian-Grassmannain and the quantity ``Maslov index'' for paths in this space based on the standard theory of Functional Analysis. Our standing point is to define the Maslov index for arbitrary paths in terms of the fundamental spectral property of the Fredh…

2003-11-27abs ↗pdf ↗

New methods show quasinormal modes can be defined using various stationary Killing vectors.

problem Proving asymptotic expansions for wave equations in Kerr-de Sitter spacetimes.
method New definition of quasinormal modes using different stationary Killing vectors.
result Horizon Killing vector fields work for analysis, simplifying the problem.

Characterizes Fredholm conditions for group-invariant pseudodifferential operators.

problem Understanding Fredholm conditions for operators on quotient spaces.
method Study of symbol CC^*-algebra and topology of primitive ideal spectrum.
result Explicit characterization of Fredholm operators in terms of principal symbol and group action.

Researchers prove Fredholm property for Dirac operator on specific spacetimes.

problem Proving Fredholm property for Dirac operator on asymptotically static spacetimes.
method Combining time-dependent scattering theory and Egorov's theorem for pseudo-differential hyperbolic systems.
result The Dirac operator is Fredholm under Atiyah-Patodi-Singer boundary conditions.

New resonance theory for Anosov flows connects spectral properties to mixing measures.

problem Defining and analyzing Ruelle-Taylor resonances for Anosov actions.
method Combining microlocal methods and J. Taylor's cohomological theory, defining Ruelle-Taylor resonances and proving Fredholm theory.
result Ruelle-Taylor resonances form a discrete subset of Cκ\mathbb{C}^κ with λ=0λ=0 being a leading resonance.

The paper studies elliptic operators on manifolds with boundary.

problem Characterizing boundary conditions for elliptic operators on manifolds.
method Using Calderón projectors and mixed order Sobolev spaces, the paper describes the space of boundary values and characterizes Fredholm and regular realisations.
result Characterization of boundary conditions for elliptic operators leading to Fredholm and regular realisations.

Classifies non-linear Fredholm maps linking to stable homotopy groups of spheres.

problem Classifying non-linear proper Fredholm maps between Hilbert spaces.
method Using stable homotopy groups of spheres to classify maps up to proper homotopy.
result Determines the non-trivial kernel of the map from stable homotopy groups to non-linear proper Fredholm maps.

Study of elliptic boundary value problems on non-compact manifolds.

problem Analyzing elliptic differential operators on manifolds with non-compact boundaries.
method Regularity theory and trace theorems for sections in the maximal domain under various assumptions.
result Systematic study of local and nonlocal boundary conditions, including the Atiyah-Patodi-Singer condition.

This is an expository article. It discusses an approach to hypoelliptic Fredholm index theory based on noncommutative methods (groupoids, C*-algebras, K-theory). The paper starts with an explicit index theorem for scalar second order differential operators on 3-manifolds that are Fredholm but not elliptic. This low-bro…

2010-01-29abs ↗pdf ↗

We show that elliptic complexes of (pseudo)differential operators on smooth compact manifolds with boundary can always be complemented to a Fredholm problem by boundary conditions involving global pseudodifferential projections on the boundary (similarly as the spectral boundary conditions of Atiyah, Patodi and Singer …

2015-10-08abs ↗pdf ↗

Study the geometry of hydrodynamics equations using diffeomorphism groups.

problem Investigate the Euler equations and surface quasi-geostrophic equation family.
method Realize equations as geodesic equations on diffeomorphism groups and analyze Riemannian exponential maps.
result Show precise conditions for non-linear Fredholm maps of index 0.

We construct a Fredholm module on self-similar sets such as the Cantor dust, the Sierpinski carpet and the Menger sponge. Our construction is a higher dimensional analogue of Connes' combinatorial construction of the Fredholm module on the Cantor set. We also calculate the Dixmier trace of two operators induced by the …

2019-12-12abs ↗pdf ↗

New Fredholm criteria for pseudodifferential operators on manifolds.

problem Characterizing the Fredholm property of GG-pseudodifferential operators.
method General Simonenko principle applied to GG-pseudodifferential operators on Sobolev spaces of sections of vector bundles.
result Derivation of novel Fredholm criteria and further characterization for finite groups.

Study shows Fredholmness of a Lorentzian Dirac operator on spacetimes.

problem Analyzing Fredholmness of a Lorentzian Dirac operator on spacetimes.
method Investigates Fredholmness of a (spatial) Γ-invariant Lorentzian Dirac operator under (anti) Atiyah-Patodi-Singer boundary conditions.
result Demonstrates Fredholmness of the operator in the von Neumann sense.

New rigidity theorems for spin fill-ins with non-negative scalar curvature.

problem Mean curvature rigidity for spin fill-ins with non-negative scalar curvature.
method Two spinorial techniques: extending boundary spinors and comparison using index theory.
result New Witten-type integral inequality for the mass of asymptotically Schwarzschild manifolds.

Let $\Y$ be a smooth connected manifold, $Σ\subset\C$ an open set and $(σ,y)\to\scrP_y(σ)$ a family of unbounded Fredholm operators DH1H2D\subset H_1\to H_2 of index 0 depending smoothly on $(y,σ)\in \Y\times Σ$ and holomorphically on σσ. We show how to associate to $\scrP$, under mild hypotheses, a smooth vector bundle …

2013-01-24abs ↗pdf ↗

We study the zeta determinant of global boundary problems of APS-type through a general theory for relative spectral invariants. In particular, we compute the zeta determinant for Dirac-Laplacian boundary problems in terms of a scattering Fredholm determinant over the boundary.

2004-06-16abs ↗pdf ↗

Derives Fredholm criteria for isotypical components from a Simonenko principle.

problem Finding Fredholm conditions for isotypical components of invariant pseudodifferential operators.
method General Simonenko's local principle and equivariant local principle for restriction to isotypical components.
result Full proof of equivariant local principle and extension of results.

Complete, conformally flat metrics of constant positive scalar curvature on the complement of kk points in the nn-sphere, k2k \ge 2, n3n \ge 3, were constructed by R\. Schoen [S2]. We consider the problem of determining the moduli space of all such metrics. All such metrics are asymptotically periodic, and we develop…

1994-06-30abs ↗pdf ↗

We investigate Seiberg-Witten theory in the presence of real structures. Certain conditions are obtained so that integer valued real Seiberg-Witten invariants can be defined. In general we study properties of the real Seiberg-Witten projection map from the point of view of Fredholm map degrees.

2009-05-03abs ↗pdf ↗