Results 21 to 30 of about 440 (138)
Berichte zur Wissenschaftsgeschichte, EarlyView.I present and discuss two drafts of remarks prepared by the mathematician Hermann Minkowski (1864–1909). They were composed in December 1907 while preparing his paper on the “Basic Equations of Electromagnetic Processes in Moving Bodies” for publication in the Proceedings of the Göttingen Academy of Sciences.
Tilman Sauer
wiley +1 more source
Front Propagation Through a Perforated Wall
Communications on Pure and Applied Mathematics, EarlyView.ABSTRACT We consider a bistable reaction– diffusion equation ut=Δu+f(u)$u_t=\Delta u +f(u)$ on RN${\mathbb {R}}^N$ in the presence of an obstacle K$K$, which is a wall of infinite span with many holes. More precisely, K$K$ is a closed subset of RN${\mathbb {R}}^N$ with smooth boundary such that its projection onto the x1$x_1$‐axis is bounded and that ...
Henri Berestycki +2 more
wiley +1 more source
Effect of Magnetic Islands on Neoclassical Heat Diffusivity in a Global Tokamak Simulation
Contributions to Plasma Physics, EarlyView.ABSTRACT Resonant magnetic perturbations (RMPs) alter magnetic field topology via island formation and can modify core transport in toroidal fusion devices. Using the global gyrokinetic particle‐in‐cell code XGC‐S, originally developed for stellarator geometries, we quantify how island topology affects neoclassical heat transport in a circular tokamak ...
Joseph X. Li +5 more
wiley +1 more source
Optical Skyrmions with Tunable or Reconfigurable Topology Using Spin‐Decoupled Metaoptics
Laser &Photonics Reviews, EarlyView.The work introduces advanced optical elements capable of generating and dynamically reconfiguring complex light patterns known as optical skyrmions. By precisely shaping light polarization at the nanoscale, a single engineered metasurface can generate and manipulate robust and tunable polarization textures in an efficient and scalable way.
Andrea Vogliardi +5 more
wiley +1 more source
Near‐Infrared Polarimetric Imaging With Nonlinear Flat‐Optics
Laser &Photonics Reviews, EarlyView.ABSTRACT A compact and broadband polarimetric imaging platform is presented, based on second‐harmonic generation (SHG) in nonlinear flat‐optics. The system employs periodic all‐dielectric AlGaAs gratings to induce polarization‐dependent SH emission, enabling pixel by pixel direct retrieval of the full Stokes vector from an input intensity distribution ...
Evgenii Menshikov +6 more
wiley +1 more source
Kuga–Satake Construction on Families of K3 Surfaces of Picard Rank 14
Mathematische Nachrichten, EarlyView.ABSTRACT The isometry between the type IV6 and the type II4 hermitian symmetric domains suggests a possible relation between suitable moduli spaces of K3 surfaces of Picard rank 14 and of polarized abelian 8‐folds with totally definite quaternion multiplication. We show how this isometry induces a geometrically meaningful map between such moduli spaces
Flora Poon
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The Two Extremal Rays of Some Hyper–Kähler Fourfolds
Mathematische Nachrichten, EarlyView.ABSTRACT We consider projective Hyper–Kähler manifolds of dimension 4 that are deformation equivalent to Hilbert squares of K3 surfaces. In case such a manifold admits a divisorial contraction, the exceptional divisor is a conic bundle over a K3 surface. A classification of lattice embeddings implies that there are five types of such conic bundles.
Federica Galluzzi, Bert van Geemen
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Mathematical Methods in the Applied Sciences, EarlyView.ABSTRACT This paper proves the existence of nontrivial solution for two classes of quasilinear systems of the type −ΔΦ1u=Fu(x,u,v)+λRu(x,u,v)inΩ−ΔΦ2v=−Fv(x,u,v)−λRv(x,u,v)inΩu=v=0on∂Ω$$ \left\{\begin{array}{l}\hfill -{\Delta}_{\Phi_1}u={F}_u\left(x,u,v\right)+\lambda {R}_u\left(x,u,v\right)\kern0.1832424242424242em \mathrm{in}\kern0.3em \Omega ...
Lucas da Silva, Marco Souto
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Quantum symmetries in 2+1 dimensions: Carroll, (a)dS-Carroll, Galilei and (a)dS-Galilei
Journal of High Energy PhysicsThere is a surge of research devoted to the formalism and physical manifestations of non-Lorentzian kinematical symmetries, which focuses especially on the ones associated with the Galilei and Carroll relativistic limits (the speed of light taken to ...
Tomasz Trześniewski
doaj +1 more source
International Journal of Mechanical System Dynamics, EarlyView.ABSTRACT The rotor system of an electrically assisted turbocharger (EAT) is composed of multiple shaft components; The nonlinear connection and contact effects make it difficult to determine the system dynamic characteristics. To improve the modeling accuracy of EAT rotor system and evaluate the influence of contact between multi‐axis components and ...
Wenchao Liang +5 more
wiley +1 more source