Results 81 to 90 of about 4,762 (252)

A tutorial on Bayesian model averaging for exponential random graph models

British Journal of Mathematical and Statistical Psychology, EarlyView.
Abstract The use of exponential random graph models (ERGMs) is becoming prevalent in psychology due to their ability to explain and predict the formation of edges between vertices in a network. Valid inference with ERGMs requires correctly specifying endogenous and exogenous effects as network statistics, guided by theory, to represent the network ...
Ihnwhi Heo, Jan‐Willem Simons, Haiyan Liu   +2 more
wiley   +1 more source

Geodesic deviation in the q-metric

European Physical Journal C: Particles and Fields
We consider the tidal forces between test particles falling along geodesics in the exterior spacetime generated by a static and axially symmetric compact matter source with a non-vanishing mass quadrupole.
A. Idrissov, K. Boshkayev, K. F. Dialektopoulos, A. Urazalina, D. Utepova   +4 more
doaj   +1 more source

Ricci Solitons on Riemannian Hypersurfaces Generated by Torse-Forming Vector Fields in Riemannian and Lorentzian Manifolds

Axioms
In this paper, we examine torse-forming vector fields to characterize extrinsic spheres (that is, totally umbilical hypersurfaces with nonzero constant mean curvatures) in Riemannian and Lorentzian manifolds.
Norah Alshehri, Mohammed Guediri
doaj   +1 more source

SDFs from Unoriented Point Clouds using Neural Variational Heat Distances

Computer Graphics Forum, EarlyView.
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, Florine Hartwig, Josua Sassen, Sergio Conti, Mirela Ben‐Chen, Martin Rumpf   +5 more
wiley   +1 more source

Non-relativistic spinning particle in a Newton-Cartan background

Journal of High Energy Physics, 2018
We construct the action of a non-relativistic spinning particle moving in a general torsionless Newton-Cartan background. The particle does not follow the geodesic equations, instead the motion is governed by the non-relativistic analog of Papapetrou ...
Andrea Barducci, Roberto Casalbuoni, Joaquim Gomis   +2 more
doaj   +1 more source

Connectivity by geodesics on globally hyperbolic spacetimes with a lightlike Killing vector field

Revista Matemática Iberoamericana, 2017
Taking a globally hyperbolic spacetime endowed with a complete lightlike Killing vector field and a complete Cauchy hypersurface, we characterize the points which can be connected by geodesics. A straightforward consequence is the geodesic connectedness of globally hyperbolic generalized plane waves with a complete Cauchy hypersurface.
BARTOLO, Rossella, Candela AM, Flores JL
openaire   +3 more sources

Controllable Intrinsic Surface Pattern Generation Using Slime Mold Simulations

Computer Graphics Forum, EarlyView.
Abstract Surface‐based pattern simulations have proven valuable for texture design and scientific visualization, but existing methods face several limitations. Most simulations either target a narrow range of pattern types (e.g. spots, branching) or support a broad range of patterns at the cost of time‐consuming parameter tuning.
Jeffrey Layton, Faramarz Samavati, Adam Runions   +2 more
wiley   +1 more source

Geodesic Distance Function Learning via Heat Flow on Vector Fields

CoRR, 2014
Learning a distance function or metric on a given data manifold is of great importance in machine learning and pattern recognition. Many of the previous works first embed the manifold to Euclidean space and then learn the distance function. However, such a scheme might not faithfully preserve the distance function if the original manifold is not ...
Binbin Lin, Ji Yang, Xiaofei He 0001, Jieping Ye   +3 more
openaire   +3 more sources

Mesh Processing Non‐Meshes via Neural Displacement Fields

Computer Graphics Forum, EarlyView.
Abstract Mesh processing pipelines are mature, but adapting them to newer non‐mesh surface representations—which enable fast rendering with compact file size—requires costly meshing or transmitting bulky meshes, negating their core benefits for streaming applications.
Yuta Noma, Zhecheng Wang, Chenxi Liu, Karan Singh, Alec Jacobson   +4 more
wiley   +1 more source

Lightlike Submanifolds of a Semi-Riemannian Manifold of Quasi-Constant Curvature

Journal of Applied Mathematics, 2012
We study the geometry of lightlike submanifolds (𝑀,𝑔,𝑆(𝑇𝑀),𝑆(𝑇𝑀⟂)) of a semi-Riemannian manifold (𝑀,̃𝑔) of quasiconstant curvature subject to the following conditions: (1) the curvature vector field ζ of 𝑀 is tangent to 𝑀, (2) the screen distribution 𝑆(
D. H. Jin, J. W. Lee
doaj   +1 more source