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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.

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114228341455 · May 202619922001200920172026
48 results for APS boundary conditions

Study perturbs APS boundary conditions for Lorentzian Dirac operators.

problem Maintaining Fredholmness of Dirac operators under perturbations of APS boundary conditions.
method Develop criteria for perturbing compact pairs of projections to remain Fredholm.
result Criteria for perturbing APS boundary conditions without losing Fredholmness.

Study well-poses Dirac operator problem with APS boundary conditions.

problem Well-posedness of Cauchy problem for Dirac operator on Lorentzian manifolds.
method Derived energy estimates, established uniqueness and existence of weak solutions, introduced mollifier operators.
result Well-posedness of Cauchy problem for Dirac operator with APS boundary conditions.

Study Dirac operators on finite warped cylinders with gauge fields.

problem Characterize spectral flow on finite warped cylinders with gauge fields.
method Identify endpoint operators, derive determinant characterization, introduce regularized APS conditions.
result Regularized APS conditions admit a spectral-flow framework, matching zero-mode sets.

New boundary conditions solve Cauchy problem for Dirac operators on spacetimes.

problem Understanding non-local boundary conditions for Dirac operators on spacetimes.
method Define and analyze a class of Lorentzian boundary conditions that are local in time and non-local in spatial directions.
result Well-posed Cauchy problem for the Dirac operator is established under these conditions.

Study reflection symmetry and APS boundary conditions on a warped cylinder.

problem Analyzing reflection symmetry and APS boundary conditions for twisted Dirac operators on a finite warped cylinder.
method Examined reflection symmetry and APS boundary conditions for twisted Dirac operators on a finite warped cylinder, considering both fixed and varying holonomy.
result Reflection symmetry lifts to a unitary symmetry under specific conditions, and the spectral flow admits an RO(O(2))-valued decomposition for fixed holonomy.

Study spectral flow on a warped cylinder with special boundary conditions.

problem Analyzing spectral flow on a warped cylinder with specific boundary conditions.
method Complexifying the twisting bundle, diagonalizing the orthogonal twist, and regrouping conjugate and reflection-paired blocks.
result Explicit formula for RO(O(2))RO(O(2))-valued spectral flow, refining ordinary spectral flow.

Physicists explain a mathematical theorem about topological insulators.

problem Mathematical formulation of APS index theorem not directly related to physical fermion system.
method Reformulated APS index theorem using η invariant of domain-wall Dirac operator.
result Equivalence between APS index and η invariant is generally true.

Under standard local boundary conditions or certain global APS boundary conditions, we get lower bounds for the eigenvalues of the Dirac operator on compact spin manifolds with boundary. Limiting cases are characterized by the existence of real Killing spinors and the minimality of the boundary.

2000-12-29abs ↗pdf ↗

We discuss the behaviour of the signature index class of closed foliated bundles under the operation of cutting and pasting. Along the way we establish several index theoretic results: we define Atiyah-Patodi-Singer (APS) index classes for Dirac-type operators on foliated bundles with boundary; we prove a relative inde…

2004-07-23abs ↗pdf ↗

New examples show positive scalar curvature metrics on manifolds with boundary that cannot be extended.

problem Positive scalar curvature metrics on manifolds with boundary that cannot be extended.
method Analytic techniques related to the prescribed scalar curvature problem in conformal geometry.
result Obstruction to positivity of conformal Laplacians given by a real-valued ξ-invariant.

We investigate the problem of calculating the Fredholm index of a geometric Dirac operator subject to local (e.g. Dirichlet and Neumann) and non-local (APS) boundary conditions posed on the strata of a manifold with corners. The boundary strata of the manifold with corners can intersect in higher codimension. To calcul…

2017-04-03abs ↗pdf ↗

Extends Atiyah-Singer Dirac operator study to non-compact spacetimes.

problem Analyzing Dirac operator on non-compact spacetimes with non-compact Cauchy hypersurface.
method Building on previous works, extends Fredholm result to non-compact Lorentzian spaces, using von Neumann algebras and Galois coverings.
result Γ-Fredholmness of the Dirac operator under APS boundary conditions.

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 ↗

The general theory of boundary value problems for linear elliptic wedge operators (on smooth manifolds with boundary) leads naturally, even in the scalar case, to the need to consider vector bundles over the boundary together with general smooth fiberwise multiplicative group actions. These actions, essentially trivial…

2013-01-24abs ↗pdf ↗

Extends Onsager's conjecture to Besov spaces on manifolds with boundary.

problem Proving Onsager's conjecture on Riemannian manifolds with boundary.
method Constructing Hodge-Neumann heat kernel, obtaining off-diagonal decay and local Bernstein estimates.
result Extends Onsager's conjecture to Besov spaces B^3,V13\widehat{B}_{3,V}^{\frac{1}{3}}.

Uniform K-homology theory applied to elliptic operators on manifolds with boundary.

problem Developing a theory to study boundary conditions for elliptic operators on non-compact manifolds.
method Theory of relative uniform K-homology, developing a relative index map.
result Uniform K-homology classes of boundary conditions and their connection to the higher ρ-invariant.

We study the index of the APS boundary value problem for a strongly Callias-type operator DD on a complete even dimensional Riemannian manifold MM (the odd dimensional case was considered in our previous paper arXiv:1706.06737). We use this index to define the relative ηη-invariant η(A1,A0)η(A_1,A_0) of two strongly Calli…

2017-08-24abs ↗pdf ↗

Paper proposes a graph model for optimal AP deployment in indoor optical wireless networks.

problem Challenges in deploying optical wireless networks due to LoS requirement and limited range.
method Graph modeling approach to identify minimum number of APs and their optimal locations.
result Optimal deployment of APs ensures connectivity and minimizes interference in indoor environments.

Index theorems for the Dirac operator allow one to study spinors on manifolds with boundary and torsion. We analyse the modifications of the boundary Chern-Simons correction and APS eta invariant in the presence of torsion. The bulk contribution must also be modified and is computed using a supersymmetric quantum mecha…

1999-01-05abs ↗pdf ↗

We propose a non-perturbative formulation of the Atiyah-Patodi-Singer(APS) index in lattice gauge theory, in which the index is given by the ηη invariant of the domain-wall Dirac operator. Our definition of the index is always an integer with a finite lattice spacing. To verify this proposal, using the eigenmode set o…

2019-10-21abs ↗pdf ↗

We show that there is a canonical construction of a zeta (Bismut-Quillen) connection on the determinant line bundle of a family of APS elliptic boundary problems and that it has curvature equal to the 2-form part of a relative eta form.

2007-12-13abs ↗pdf ↗

We provide an interpretation of the APS index theorem of Piazza-Schick and Zeidler in terms of coarse homotopy theory. On the one hand we propose a motivic version of the boundary value problem, the index theorem, and the associated secondary invariants. On the other hand, we discuss in detail how the abstract version …

2018-06-10abs ↗pdf ↗

The class of metrizable spaces MM with the following approximation property is introduced and investigated: MAP(n,0)M\in AP(n,0) if for every $\e>0$ and a map $g\colon\I^n\to M$ there exists a 0-dimensional map $g'\colon\I^n\to M$ which is $\e$-homotopic to gg. It is shown that this class has very nice properties. For exam…

2008-01-20abs ↗pdf ↗

A geometric structure (FAP-structure), having both absolute parallelism and Finsler properties, is constructed. The building blocks of this structures are assumed to be functions of position and direction. A non-linear connection emerges naturally and is defined in terms of the building blocks of the structure. Two lin…

2008-01-07abs ↗pdf ↗

Study improves scalability of cell-free massive MIMO networks by optimizing UE-AP association.

problem Optimizing UE-AP association in cell-free massive MIMO networks.
method Deep learning algorithm using Bidirectional Long Short-Term Memory cells and hybrid probabilistic weight updating.
result Enhanced scalability without retraining, robust against pilot contamination.

Given two unitary involutions σ1σ_{1} and σ2σ_{2} satisfying Gσi=σiGG σ_{i} = - σ_{i} G on kerBker B on a compact manifold with cylindrical end, M. Lesch, K. Wojciechowski ([LW]) and W. Müller ([M]) established the formula describing the difference of two eta-invariants with the APS boundary conditions associated with σ1σ_{1}

2004-08-13abs ↗pdf ↗

Study optimal portfolio selection using average and current profitability of risky assets.

problem Continuous-time mean-variance portfolio selection in time-varying financial markets.
method Introduced AP and CP indexes; estimated AP and CP using second-order variation of an auxiliary wealth process.
result Estimations of AP and CP are more accurate than traditional MLE.

AP-CDE uses NF to estimate high-dimensional conditional densities, improving interpretability.

problem Estimating conditional densities for high-dimensional responses like images.
method Extends NF neural networks to handle high-dimensional yy with a latent zz.
result Improves interpretation of latent components, especially zPz_P.

Detects project management anti-patterns using code and issue data.

problem Detecting project management anti-patterns requires expert judgment and is expensive.
method Convert descriptions to detectable metrics, quantify deviations, and optimize patterns.
result Automatic calibration enhances pattern detection and severity assessment.

We study the index of the APS boundary value problem for a strongly Callias-type operator D on a complete Riemannian manifold MM. We show that this index is equal to an index on a simpler manifold whose boundary is a disjoint union of two complete manifolds N0N_0 and N1N_1. If the dimension of MM is odd we show that …

2017-06-21abs ↗pdf ↗

Study proves positivity of quasi-local masses in general relativity using spinors.

problem Proving the positivity of quasi-local masses in general relativity.
method Using spinors and solving Dirac equation on compact Riemannian manifolds with boundary conditions.
result Gravitational mass bounded by a spacelike topological 2-sphere is non-negative, vanishing only in Minkowski space.

The paper presents a method to improve trust in deep learning models for crop and weed classification.

problem Lack of user trust in deep learning models for precision agriculture due to their complexity and uncertainty.
method Group-conditional conformal prediction via quantile regression calibration.
result The proposed method provides valid statistical guarantees on the predictive performance of deep learning models.