Results 31 to 40 of about 52,233 (277)

A de Sitter Farey Tail

, 2011
We consider quantum Einstein gravity in three dimensional de Sitter space. The Euclidean path integral is formulated as a sum over geometries, including both perturbative loop corrections and non-perturbative instanton corrections coming from geometries ...
Castro, Alejandra, Lashkari, Nima, Maloney, Alexander   +2 more
core   +1 more source

Parametric Surfaces for Elliptic and Hyperbolic Geometries

Mathematics
Background/Objectives: In computer graphics, virtual worlds are constructed and visualized through algorithmic processes. These environments are typically populated with objects defined by mathematical models, traditionally based on Euclidean geometry ...
László Szirmay-Kalos, András Fridvalszky, László Szécsi, Márton Vaitkus   +3 more
doaj   +1 more source

Gravity Dual for a Model of Perception

, 2011
One of the salient features of human perception is its invariance under dilatation in addition to the Euclidean group, but its non-invariance under special conformal transformation.
Bialek, Bialek, Coleman, d’Agostini, Gubser, Ho, Ho, Hull, Mueck, Nakayama, Nakayama, Nakayama, Polchinski, Riva, Wiskott, Witten, Yu Nakayama, Zamolodchikov   +17 more
core   +1 more source

Karl Popper's Philosophical Breakthrough [PDF]

, 2004
Despite his well-known deductivism, in his early (unpublished) writings, Popper held an inductivist position. Up to 1929 epistemology entered Popper's reflections only as far as the problem was that of the justification of the scientific character of ...
Gattei, Stefano
core   +1 more source

Holographic excited states in AdS black holes

Journal of High Energy Physics, 2019
We have recently presented a geometry dual to a Schwinger-Keldysh closed time contour, with two equal β/2 length Euclidean sections, which can be thought of as dual to the Thermo Field Dynamics formulation of the boundary CFT.
Marcelo Botta-Cantcheff, Pedro J. Martínez, Guillermo A. Silva   +2 more
doaj   +1 more source

Exponential stability of the nonlinear Schrödinger equation with locally distributed damping on compact Riemannian manifold

Advances in Nonlinear Analysis, 2020
In this paper, we consider the following nonlinear Schrödinger equation:
Yang Fengyan, Ning Zhen-Hu, Chen Liangbiao   +2 more
doaj   +1 more source

Fundamental Symmetries and Spacetime Geometries in Gauge Theories of Gravity—Prospects for Unified Field Theories

Universe, 2020
Gravity can be formulated as a gauge theory by combining symmetry principles and geometrical methods in a consistent mathematical framework. The gauge approach to gravity leads directly to non-Euclidean, post-Riemannian spacetime geometries, providing ...
Francisco Cabral, Francisco S. N. Lobo, Diego Rubiera-Garcia   +2 more
doaj   +1 more source

Hawking Radiation from Black Holes Formed During Quantum Tunneling

, 1994
We study the behaviour of scalar fields on background geometries which undergo quantum tunneling. The two examples considered are a moving mirror in flat space which tunnels through a potential barrier, and a false vacuum bubble which tunnels to form a ...
Aurilia, Aurilia, Banks, Berezin, Berezin, Blau, Brout, Casher, Davies, Farhi, Fischler, Hawking, Hawking, Kandrup, Kandrup, Kodama, Kodama, Lake, Lake, Lapchinsky, Lavrelashvili, Maeda, Per Kraus, Regge, Rubakov, Rubakov, Sato, Sato, Sato, Unruh   +29 more
core   +1 more source

Multimodal Data‐Driven Microstructure Characterization

Advanced Engineering Materials, EarlyView.
A self‐consistent autonomous workflow for EBSP‐based microstructure segmentation by integrating PCA, GMM clustering, and cNMF with information‐theoretic parameter selection, requiring no user input. An optimal ROI size related to characteristic grain size is identified.
Qi Zhang, Santiago Benito, Özge Özgün, Sebastian Weber, Markus Stricker   +4 more
wiley   +1 more source

Predicting Atomic Charges in MOFs by Topological Charge Equilibration

Advanced Functional Materials, EarlyView.
An atomic charge prediction method is presented that is able to accurately reproduce ab‐initio‐derived reference charges for a large number of metal–organic frameworks. Based on a topological charge equilibration scheme, static charges that fulfill overall neutrality are quickly generated.
Babak Farhadi Jahromi, Sumukh Shankar Sharadaprasad, Rochus Schmid   +2 more
wiley   +1 more source