Results 81 to 90 of about 112,001 (232)
Projective Vector Fields on Semi-Riemannian Manifolds
This paper explores the properties of projective vector fields on semi-Riemannian manifolds. The main result establishes that if a projective vector field P on such a manifold is also a conformal vector field with potential function ψ and the vector ...
Norah Alshehri, Mohammed Guediri
doaj +1 more source
Abundant Superintegrable Systems and Hessian Structures [PDF]
We show that a large class of non-degenerate second-order (maximally) superintegrable systems gives rise to Hessian structures, which admit natural (Hessian) coordinates adapted to the superintegrable system.
Vollmer, Andreas +1 more
core +1 more source
Model fit and parameter uncertainty in amortized variational inference based item response theory
Abstract Amortized variational inference (AVI) has become a popular, computationally efficient alternative to marginal maximum likelihood estimation (MML) for estimating high‐dimensional item response theory models on large datasets. However, currently the AVI framework lacks methods to assess model fit and determine parameter uncertainty.
K. Veldkamp +3 more
wiley +1 more source
The Geometry of (p,q)-Harmonic Maps
This paper studies (p,q)-harmonic maps by unified geometric analytic methods. First, we deduce variation formulas of the (p,q)-energy functional. Second, we analyze weakly conformal and horizontally conformal (p,q)-harmonic maps and prove Liouville ...
Yan Wang, Kaige Jiang
doaj +1 more source
SDFs from Unoriented Point Clouds using Neural Variational Heat Distances
We propose a novel variational approach for computing neural Signed Distance Fields (SDF) from unoriented point clouds. We first compute a small time step of heat flow (middle) and then use its gradient directions to solve for a neural SDF (right). Abstract We propose a novel variational approach for computing neural Signed Distance Fields (SDF) from ...
Samuel Weidemaier +5 more
wiley +1 more source
The framework of the research whose part of results are published in this work is the category of real vector bundles over finite dimensional differentiable manifolds. The objects of studies are gauge structures on these vector bundles. We are interested
Michel Nguiffo Boyom
doaj +1 more source
SPECIAL RICCI–HESSIAN EQUATIONS ON KÄHLER MANIFOLDS
Abstract Special Ricci–Hessian equations on Kähler manifolds $(M,g)$ , as defined by Maschler [‘Special Kähler–Ricci potentials and Ricci solitons’,
ANDRZEJ DERDZINSKI, PAOLO PICCIONE
openaire +2 more sources
Dubrovin's duality for F-manifolds with eventual identities [PDF]
A vector field <i>E</i> on an <i>F</i>-manifold (M, o, e) is an eventual identity if it is invertible and the multiplication X*Y := X o Y o E^{-1} defines a new F-manifold structure on <i>M</i>.
Ian A.B. Strachan +3 more
core +1 more source
Abstract While semi‐analytical boundary handling techniques have proven effective for modeling particle‐based fluid‐solid interactions, they can become unstable when applied to mesh boundaries undergoing dynamic motion or featuring complex, sharp geometries.
Junyuan Liu +5 more
wiley +1 more source
A General Type of Almost Contact Manifolds [PDF]
Among almost contact manifolds Sasakian manifolds, Kenmotsu manifolds (called also “a certain class of almost contact manifolds”) and cosymplectic manifolds have been studied by many authors.
Catalin Angelo Ioan
core

