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We give a purely analytic construction of a self-similar local regular Dirichlet form on the Sierpi\'nski carpet using approximation of stable-like non-local closed forms which gives an answer to an open problem in analysis on fractals.

Functional Analysis · Mathematics 2018-11-09 Alexander Grigor'yan , Meng Yang

We complete the `paraxial' (small-angle) ray optics cloaking formalism presented previously [Choi and Howell, Opt. Express 22, 29465 (2014)], by extending it to the full-field of light. Omnidirectionality is then the only relaxed parameter…

Optics · Physics 2015-06-11 Joseph S. Choi , John C. Howell

We present the design, fabrication and performance test of a quasi three-dimensional carpet cloak made of normal dielectric in the microwave regime. Taking advantage of a simple linear coordinate transformation we design a carpet cloak with…

Optics · Physics 2011-09-30 Xiaofei Xu , Yijun Feng , Shuai Xiong , Jinlong Fan , Jun-Ming Zhao , Tian Jiang

The chapter contains a detailed presentation of the surface integral theory for modelling light diffraction by surface-relief diffraction gratings having a one-dimensional periodicity. Several different approaches are presented, leading…

Optics · Physics 2014-06-03 Daniel Maystre , Evgeny Popov

Conformal prediction (CP) is a wrapper around traditional machine learning models, giving coverage guarantees under the sole assumption of exchangeability; in classification problems, for a chosen significance level $\varepsilon$, CP…

Machine Learning · Computer Science 2023-02-23 Javier Abad , Umang Bhatt , Adrian Weller , Giovanni Cherubin

Fundamental bounds on the performance of monochromatic scattering-cancellation and field-zeroing cloaks made of prescribed linear passive materials occupying a predefined design region are formulated by projecting field quantities onto a…

Optics · Physics 2021-07-06 Lukas Jelinek , Mats Gustafsson , Miloslav Capek , Kurt Schab

In this paper, we bend a closed Riemannian manifold in the conformal class, through solving a fully nonlinear equation. As a result, we prove that each metric of quasi-negative Ricci curvature is conformal to a metric with negative Ricci…

Differential Geometry · Mathematics 2022-11-02 Rirong Yuan

An elliptic cylindrical wave expansion method by using Mathieu functions is developed to obtain the scattering field for a two-dimensional elliptic cylindrical invisibility cloak. The cloak material parameters are obtained from the spatial…

Computational Physics · Physics 2008-08-12 E. Cojocaru

This paper introduces a conformal inference method to evaluate uncertainty in classification by generating prediction sets with valid coverage conditional on adaptively chosen features. These features are carefully selected to reflect…

Machine Learning · Statistics 2024-10-31 Yanfei Zhou , Matteo Sesia

We prove that, for arbitrary three-dimensional transformation-based invisibility cloaking of an object above a ground plane or of isolated object, there are practical constraints that increase with the object size. In particular, we show…

Optics · Physics 2011-08-15 Hila Hashemi , A. Oskooi , J. D. Joannopoulos , Steven G. Johnson

We present a theory for the cloaking of arbitrarily-shaped objects and demonstrate electromagnetic scattering-cancellation through designed homogeneous coatings. First, in the small-particle limit, we expand the dipole moment of a coated…

Mesoscale and Nanoscale Physics · Physics 2014-05-26 Carlo Forestiere , Luca Dal Negro , Giovanni Miano

Conformal prediction constructs a confidence set for an unobserved response of a feature vector based on previous identically distributed and exchangeable observations of responses and features. It has a coverage guarantee at any nominal…

Machine Learning · Statistics 2022-12-08 Eugene Ndiaye , Ichiro Takeuchi

Transformation Acoustics emerged in the mid-2000s, initiating a new paradigm of metamaterial designs. One of the most compelling designs, the invisibility cloak, holds promise for stealth and noise reduction applications in aviation.…

Applied Physics · Physics 2024-11-07 Levi T. Kaganowich , Deepak C. Akiwate , Trevor J. Cox , Olga Umnova

We present the general theory of curves in conformal geometry using tractor calculus. This primarily involves a tractorial determination of distinguished parametrizations and relative and absolute conformal invariants of generic curves. The…

Differential Geometry · Mathematics 2018-05-02 Josef Šilhan , Vojtěch Žádník

A near-perfect, non-singular cylindrical invisibility cloak with diamond cross section is achieved by a two-step coordinate transformation. A small line segment is stretched and then blown up into a diamond space, and finally the cloak…

Optics · Physics 2011-12-21 Wei Li , Jianguo Guan , Zhigang Sun , Wei Wang , Qingjie Zhang

We propose an analytical approach to the conformal mapping of (rectangular) polygons based on the theory of Riemann surfaces and theta functions.

Complex Variables · Mathematics 2015-05-30 Andrei B. Bogatyrev

Invisible cloak has long captivated the popular conjecture and attracted intensive research in various communities of wave dynamics, e.g., optics, electromagnetics, acoustics, etc. However, their inhomogeneous and extreme parameters imposed…

Materials Science · Physics 2013-02-05 Tiancheng Han , Baowen Li , Cheng-Wei Qiu

The governing equation for elastic waves in flexural plates is not form invariant, and hence designing a cloak for such waves faces a major challenge. Here, we present the design of a perfect broadband cloak for flexural waves through the…

Classical Physics · Physics 2017-06-28 Ahmad Zareei , Mohammad-Reza Alam

We develop a very general theory on the regularized approximate invisibility cloaking for the wave scattering governed by the Helmholtz equation in any space dimensions via the approach of transformation optics.

Analysis of PDEs · Mathematics 2015-03-04 Jingzhi Li , Hongyu Liu , Luca Rondi , Gunther Uhlmann

The design rules of transformation optics generally lead to spatially inhomogeneous and anisotropic impedance-matched magneto-dielectric material distributions for, e.g., free-space invisibility cloaks. Recently, simplified anisotropic…

Optics · Physics 2015-06-11 Jad C. Halimeh , Martin Wegener
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