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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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74149223297 · Jun 202019922001200920172026
48 results for essential conformal transformations

New compact examples of pseudo-Kähler manifolds with essential conformal transformations found.

problem Existence of essential conformal transformations in pseudo-Riemannian manifolds.
method Construction of compact locally conformally pseudo-Kähler manifolds with essential conformal transformations.
result Found compact examples of pseudo-Kähler manifolds with essential conformal transformations that are not conformally flat.

Study on conformal transformations of Cahen-Wallach spaces, focusing on fixed points and discontinuous groups.

problem Characterizing conformal transformations of Cahen-Wallach spaces.
method Analyzing conformal transformations of indecomposable Lorentzian symmetric spaces, focusing on fixed points and discontinuous groups.
result Essential conformal transformations of conformally curved Cahen-Wallach spaces have fixed points, and such transformations cannot centralize essential homotheties.

Classifies 1-connected Lorentzian manifolds with essential conformal groups.

problem Classifying Lorentzian manifolds with specific conformal groups.
method Proves existence of a metric making the manifold homogeneous and plane wave.
result Completes the classification of 1-connected Lorentzian manifolds with transitive conformal groups.

We study pseudo-Riemanniasn manifolds (M,g)(M,g) with transitive group of conformal transformation which is essential, i.e. does not preserves any metric conformal to gg. All such manifolds of Lorentz signature with non exact isotropy representation of the stability subalgebra are described. A construction of essential c…

2016-11-10abs ↗pdf ↗

Classifies conformal transformations in spacetimes without observer horizons.

problem Understanding conformal transformations in spacetimes without observer horizons.
method Proves classification of conformal transformations into two types: escaping and non-escaping.
result Conformal transformations of Einstein's static universe are classified.

Study of Lorentzian manifolds with specific transformations.

problem Characterizing Lorentzian manifolds with essential pseudo-groups of local conformal transformations.
method Generalizing recent results, using Gromov's theory of rigid transformations.
result Locally conformally homogeneous Lorentzian manifolds are either conformally flat or locally conformally equivalent to homogeneous plane waves.

We construct the first known examples of compact pseudo-Riemannian manifolds having an essential group of conformal transformations, and which are not conformally flat. Our examples cover all types (p,q)(p,q), with 2pq2 \leq p \leq q.

2012-11-03abs ↗pdf ↗

For a conformal vector field ξξ on a Riemannian manifold, we say that a point is essential if there is no local metric in the conformal class for which ξξ is Killing. We show that the only essential points are isolated zeros of ξξ. As an application, we show that every connected component of the zero set of ξξ is t…

2010-02-02abs ↗pdf ↗

Compact complex manifolds with specific group actions are conformally flat.

problem Compact complex manifolds with invariant conformal holomorphic structures.
method Study of manifolds with transitive and essentially acting complex semi-simple Lie groups.
result If a complex semi-simple Lie group acts transitively and essentially, the manifold is conformally flat.

Improved text classification performance through conformal transformations of kernels.

problem Text document categorization in high-dimensional spaces.
method Introduced new Gaussian Cosine kernel and two conformal transformations.
result Conformal transformations significantly improve kernel performance, especially for sub-optimal kernels.

Improved multivariate conformal prediction by standardizing residuals.

problem Weak conditional coverage in heteroskedastic multivariate settings.
method Natural extension of univariate normalization to multivariate setting, whitening residuals and standardizing local variance.
result Standardized residuals yield asymptotic conditional coverage under certain distributions.

Using the theory of Weyl structures, we give a natural generalization of the notion of essential conformal structures and conformal Killing fields to arbitrary parabolic geometries. We show that a parabolic structure is inessential whenever the automorphism group acts properly on the base space. As a corollary of the g…

2010-11-01abs ↗pdf ↗

The classical Liouville Theorem on conformal transformations determines local conformal transformations on the Euclidean space of dimension 3\geq 3. Its natural adaptation to the general framework of Riemannian structures is the 2-rigidity of conformal transformations, that is such a transformation is fully determined…

2014-11-20abs ↗pdf ↗

A new characterization of conformal transformations is given. By use of this, the general form of conformal transformation on two-dimensional Minkowski space is given and its conformal structure is analyzed.

2013-11-05abs ↗pdf ↗

Compact Finslerian manifolds don't admit non-trivial circle-preserving transformations.

problem Characterizing Finslerian manifolds without circle-preserving transformations.
method Analyzing critical points of conformal transformations to prove manifold rigidity.
result Compact Finslerian manifolds are Riemannian and conformally diffeomorphic to standard spheres, Euclidean spaces, or hyperbolic spaces.

This research examines anisotropic conformal transformations of pseudo-Finsler surfaces.

problem Investigating anisotropic conformal transformations of conic pseudo-Finsler surfaces.
method Using modified Berwald frame, the study finds necessary and sufficient conditions for anisotropic conformal transformations and analyzes geometric properties.
result Necessary and sufficient conditions for anisotropic conformal transformations of pseudo-Finsler surfaces are derived.

We study several problems concerning conformal transformation on metric measure spaces, including the Sobolev space, the differential structure and the curvature-dimension condition under conformal transformations. This is the first result about preservation of lower curvature bounds under perturbation, which is new ev…

2015-11-10abs ↗pdf ↗

ST-BCP narrows the coverage gap in BCP by transforming nonconformity scores.

problem The looseness in BCP's coverage guarantee due to Markov's inequality.
method Introduces a data-dependent transformation of nonconformity scores.
result Reduces the average coverage gap from 4.20% to 1.12% on benchmarks.

Classification of Finslerian spaces with nontrivial concircular transformations.

problem Classifying Finslerian spaces with nontrivial concircular transformations.
method Proving the existence of at most two critical points in a conformal circle-preserving transformation and presenting a diffeomorphism classification based on these critical points.
result Presented a diffeomorphism classification of Finslerian manifolds that admit nontrivial conformal circle-preserving transformations.

In this article, we prove several results about the extension to the boundary of conformal immersions from an open subset ΩΩ of a Riemannian manifold LL, into another Riemannian manifold NN of the same dimension. In dimension n3n \geq 3, and when the (n1)(n-1)-dimensional Hausdorff measure of Ω\partial Ω is zero, we …

2011-10-05abs ↗pdf ↗

Synthetic approach to conformal transformations in metric and Lorentzian spaces.

problem Defining consistent conformal transformations in spaces of low regularity.
method Introducing conformal transformations in metric and Lorentzian spaces, focusing on Lorentzian pre-length spaces.
result Established a consistent notion of conformal length and proved its properties.

Proves rigidity of certain transformations on specific geometric manifolds.

problem Rigidity of conformal circle-preserving transformations on Berwaldian manifolds.
method Analyzes properties of Berwaldian manifolds and flag curvatures.
result Rigidity condition for nontrivial conformal circle-preserving transformations.

We consider several transformation groups of a locally conformally Kähler manifold and discuss their inter-relations. Among other results, we prove that all conformal vector fields on a compact Vaisman manifold which is neither locally conformally hyperkähler nor a diagonal Hopf manifold are Killing, holomorphic and th…

2008-12-16abs ↗pdf ↗

The connected components of the zero set of any conformal vector field vv, in a pseudo-Riemannian manifold (M,g)(M,g) of arbitrary signature, are of two types, which may be called `essential' and `nonessential'. The former consist of points at which vv is essential, that is, cannot be turned into a Killing field by a lo…

2011-12-01abs ↗pdf ↗

While conformal transformations of the plane preserve Laplace's equation, Lorentz-conformal mappings preserve the wave equation. We discover how simple geometric objects, such as quadrilaterals and pairs of crossing curves, are transformed under nonlinear Lorentz-conformal mappings. Squares are transformed into curvili…

2013-06-05abs ↗pdf ↗

Semisimple Lie groups act transitively on pseudo-Riemannian manifolds, making them flat.

problem Understanding actions of semisimple Lie groups on pseudo-Riemannian manifolds.
method Analyzing the pseudo-Riemannian Lichnerowicz conjecture in homogeneous settings.
result Compact pseudo-Riemannian manifolds on which a semisimple group acts conformally, essentially and transitively, are conformally flat.

Study explores solvable Lie groups' actions on closed Lorentzian manifolds.

problem Understanding conformal actions of solvable Lie groups on closed Lorentzian manifolds.
method Analyzes the identity component of the conformal group and uses algebraic hypotheses.
result Establishes conditions for conformal flatness and local embeddings.

One of the most challenging problems in the domain of 2-D image or 3-D shape is to handle the non-rigid deformation. From the perspective of transformation groups, the conformal transformation is a key part of the diffeomorphism. According to the Liouville Theorem, an important part of the conformal transformation is t…

2018-08-30abs ↗pdf ↗

The study classifies conformal biharmonic and k-polyharmonic maps between space forms.

problem Classifying conformal biharmonic and k-polyharmonic maps between space forms.
method Proving conditions for proper biharmonic and k-polyharmonic maps between space forms.
result Proper k-polyharmonic conformal maps exist if and only if the dimension is 2k.

A geodesic circle in Finsler geometry is a natural extension of that in a Euclidean space. In this paper, we apply Lie derivatives and the Cartan YY-connection to study geodesic circles and (infinitesimal) concircular transformations on a Finsler manifold. We characterize a concircular vector field with some PDEs on t…

2017-07-10abs ↗pdf ↗

The paper studies anisotropic conformal changes in pseudo-Finsler surfaces.

problem Investigating geometric properties under anisotropic conformal transformations.
method Analyzing geometric objects like Berwald, Landsberg, and Douglas tensors under anisotropic conformal transformations.
result Necessary and sufficient conditions for various geometric properties under anisotropic conformal transformations.

The abstract discusses transformations on statistical and semi-Weyl manifolds with torsion.

problem Invariance and structure preservation under conformal-projective transformations.
method Proof of invariance and preservation of structures under conformal-projective transformations.
result Semi-Weyl and statistical structures with torsion are invariant under conformal-projective transformations.