Results 61 to 70 of about 14,983 (246)

Coordinate‐ and Spacetime‐Independent Quantum Physics

Annalen der Physik, Volume 538, Issue 1, January 2026.
This article studies in the framework of quantum field theory in curved spacetime, if there exists a single zero‐rank‐tensor solution of a Klein‐Gordon PDE, being valid at once for the depicted spacetimes. The answer is shown to be affirmative, even for a class of such solutions having the standard applications in particle physics. ABSTRACT The concept
Viacheslav A. Emelyanov, Daniel Robertz
wiley   +1 more source

The Casimir Energy for a Hyperboloid Facing a Plate in the Optical Approximation

, 2004
We study the Casimir energy of a massless scalar field that obeys Dirichlet boundary conditions on a hyperboloid facing a plate. We use the optical approximation including the first six reflections and compare the results with the predictions of the ...
A. Scardicchio, A. Scardicchio, B. V. Derjagin, H. B. G. Casimir, H. Gies, M. Klein, O. Schröder, R. L. Jaffe, W. H. Press   +8 more
core   +1 more source

Different Transient Phenomena at the Edges of Traveling Foreshocks

Journal of Geophysical Research: Space Physics, Volume 131, Issue 1, January 2026.
Abstract Past kinetic simulations and spacecraft observations have shown that traveling foreshocks (TFs) are bounded by either foreshock compressional boundaries (FCBs) or foreshock bubbles (FBs). Here we present four TFs with a different kind of structure appearing at one of their edges.
Primož Kajdič, Xochitl Blanco‐Cano, Diana Rojas‐Castillo, Nojan Omidi   +3 more
wiley   +1 more source

Provable properties of asymptotic safety in f(R) approximation

Journal of High Energy Physics, 2022
We study an f(R) approximation to asymptotic safety, using a family of non-adaptive cutoffs, kept general to test for universality. Matching solutions on the four-dimensional sphere and hyperboloid, we prove properties of any such global fixed point ...
Alex Mitchell, Tim R. Morris, Dalius Stulga   +2 more
doaj   +1 more source

Predictive Modeling and Equation Formulation for 3D‐Printed Reinforced Concrete Beams

Advances in Materials Science and Engineering, Volume 2026, Issue 1, 2026.
This study focuses on developing predictive models and design equations for 3D‐printed reinforced concrete beams, utilizing machine learning to enhance the accuracy of structural analysis. The research aimed to create a novel equation for predicting bending moments, considering factors like tensile strength, compressive strength, and reinforcement ...
Paschal Chimeremeze Chiadighikaobi, Mohammad Hematibahar, Amirali Milani, Makhmud Kharun, Qais Abdulrahman Ali Qais, Mohammad Rezwan Habib   +5 more
wiley   +1 more source

Fourier and Gegenbauer expansions for a fundamental solution of the Laplacian in the hyperboloid model of hyperbolic geometry

, 2012
Due to the isotropy $d$-dimensional hyperbolic space, there exist a spherically symmetric fundamental solution for its corresponding Laplace-Beltrami operator.
Abramowitz M, Andrews G E, Beltrami E, Bers L, Byrd P F, Cohl H S, Cohl H S, Cohl H S, E G Kalnins, Erdélyi A, Erdélyi A, Fano U, Folland G B, Fox L, Gilbarg D, Gradshteyn I S, Grigor’yan A A, Grigor’yan A A, Grigor’yan A A, H S Cohl, Helgason S, Izmest’ev A A, Kalnins E G, Lee J M, Livio M, Losev A G, Magnus W, Morse P M, Olevskii˘ M N, Olver F W J, Olver F W J, Schoen R, Thurston W P, Trudeau R J, Vilenkin N Ja   +34 more
core   +2 more sources

Strongly Coupled Exciton–Hyperbolic‐Phonon‐Polariton Hybridized States in hBN‐Encapsulated Biased Bilayer Graphene

Advanced Optical Materials, Volume 13, Issue 35, December 12, 2025.
Excitons in biased bilayer graphene are electrically tunable excitations in the mid‐infrared (MIR) spectrum, where optical transitions are typically scarce. In this work, it is demonstrated that when the bilayer is encapsulated in hexagonal‐boron‐nitride (hBN)—a material supporting optical phonons and hyperbolic‐phonon‐polaritons (HPhPs) in the MIR—the
Tomer Eini, N. M. R. Peres, Yarden Mazor, Itai Epstein   +3 more
wiley   +1 more source

Dynamical Ambiguities in Singular Gravitational Field

, 1997
We consider particle dynamics in singular gravitational field. In 2d spacetime the system splits into two independent gravitational systems without singularity.
George Jorjadze, Jackiw R, Jorjadze G, Kirillov A A, Reed M, Seiberg N, Wlodzimierz Piechocki, Zhelobenko D P   +7 more
core   +1 more source

Structural Detailing of Material Extrusion Additively Manufactured 2D Metamaterials With Rigid Inclusions

PAMM, Volume 25, Issue 4, December 2025.
ABSTRACT Metamaterials are artificially designed structures that exhibit tailored mechanical properties. These properties result primarily from their underlying small‐scale architecture and can therefore be improved by adapting this structure. In this work, the mechanical behaviour of the two‐dimensional projection of the underlying structure is ...
Antonia Dönitz, Franka Kurpjuhn, Igor Berinskii, Vladimir Popov, Wolfgang H. Müller, Christina Völlmecke   +5 more
wiley   +1 more source

On Asymptotic Flatness and Lorentz Charges

, 2011
In this paper we establish two results concerning four-dimensional asymptotically flat spacetimes at spatial infinity. First, we show that the six conserved Lorentz charges are encoded in two unique, distinct, but mutually dual symmetric divergence free ...
Compère, Geoffrey, Dehouck, François, Virmani, Amitabh   +2 more
core   +1 more source