English
Related papers

Related papers: Low-Pass Filters: Commentary on a Remark by Feynma…

200 papers

In his book \emph{Topics in Analytic Number Theory}, Hans Rademacher conjectured that the limits of certain sequences of coefficients that arise in the ordinary partial fraction decomposition of the generating function for partitions of…

Number Theory · Mathematics 2018-12-05 Andrew V. Sills , Doron Zeilberger

We derive Bethe's formula for the Lamb shift by extending Feynman's suggestion that the shift could be interpreted as the change, due to the presence of the atom, in electromagnetic field energy. This approach is based on measurable…

Quantum Physics · Physics 2025-04-09 Peter W. Milonni , Paul R. Berman , Kanu Sinha

We re-examine the constraints imposed by causality and unitarity on the low-energy effective field theory expansion of four-particle scattering amplitudes, exposing a hidden "totally positive" structure strikingly similar to the positive…

High Energy Physics - Theory · Physics 2023-01-11 Nima Arkani-Hamed , Tzu-Chen Huang , Yu-tin Huang

We consider light ray reflections in $n$-dimensional semi-infinite tube, for $n\geq 3$, made of Lambertian material. The source of light is placed far away from the exit, and the light ray is assumed to reflect so that the distribution of…

Probability · Mathematics 2016-07-01 Krzysztof Burdzy , Tvrtko Tadić

We compute the real and imaginary parts of the electric permittivities and magnetic permeabilities for relativistic electrons from quantum electrodynamics at finite temperature and density. A semiclassical approximation establishes the…

Quantum Physics · Physics 2018-03-14 C. A. A. de Carvalho

A model for quantum Zeno effect based upon an effective Schr\"odinger equation originated by the path-integral approach is developed and applied to a two-level system simultaneously stimulated by a resonant perturbation. It is shown that…

Quantum Physics · Physics 2009-10-30 Roberto Onofrio , Carlo Presilla , Ubaldo Tambini

The widely-accepted theoretical treatment of the electromagnetic boundary problem of evanescent wave transfer at an interface between a normal medium of n=1 and an ideal negative index medium of n=-1 neglects the non-zero induced surface…

Optics · Physics 2013-06-12 Weiguo Yang , Michael A. Fiddy

We derive positivity bounds on low energy effective field theories which admit gapped, analytic, unitary, Lorentz invariant, and possibly non-local UV completions, by considering 2 to 2 scatterings of Jaffe fields whose…

High Energy Physics - Theory · Physics 2019-06-14 Junsei Tokuda

Negative refraction, which reverses many fundamental aspects of classical optics, can be obtained in systems with negative magnetic permeability and negative dielectric permittivity. This Letter documents an experimental realization of…

Strongly Correlated Electrons · Physics 2007-05-23 A. Pimenov , P. P. Przyslupski , B. Dabrowski , A. Loidl

We discuss path integrals for quantum mechanics with a potential which is a perturbation of the upside-down oscillator. We express the path integral (in the real time) by the Wiener measure. We obtain the Feynman integral for perturbations…

High Energy Physics - Theory · Physics 2023-05-23 Z. Haba

In 1971 Feynman, Kislinger and Ravndal [1] proposed Lorentz-invariant differential equation capable to describe relativistic particle with mass and internal space-time structure. By making use of new variables that differentiate between…

High Energy Physics - Theory · Physics 2009-09-29 Paul Korbel

One of Feynman's greatest contributions to physics was the interpretation of negative energies as antimatter in quantum field theory. A key component of this interpretation is the Feynman propagator, which seeks to describe the behavior of…

Quantum Physics · Physics 2017-05-16 R. E. Kastner

One of the concepts of Relativity theory that challenges conventional intuition the most is time dilation and length contraction. Usual approaches for describing relativistic effects in quantum systems merely postulate the consequences of…

Quantum Physics · Physics 2024-02-27 Esteban Martínez-Vargas

A unified, consistent and simple view of the Faraday law of induction is presented, which consists of two points: discriminating the lab- from the rest-frame electric field and understanding it is the impossibility for both fields to vanish…

Classical Physics · Physics 2007-05-23 Dorothea Hahn , Mario Liu

Path integrals developed by Richard Feynman have been an important tool in Physics in studying quantum field theory. In mathematics, it has also been widely used in providing formal proofs in the study of Index theorem and asymptotic…

Probability · Mathematics 2017-02-23 Zhehua Li

Although various limits on the predicability of physical phenomena as well as on physical knowables are commonly established and accepted, we challenge their ultimate validity. More precisely, we claim that fundamental limits arise only…

History and Philosophy of Physics · Physics 2012-12-10 Cristian S. Calude , Karl Svozil

A new approach to producing a composite material with negative refraction index is demonstrated. It is shown that a photonic structure consisting of two dielectric materials, with positive and negative dielectric permittivities, can support…

Optics · Physics 2007-05-23 Gennady Shvets

Hardy's paradox is analysed within Feynman's formulation of quantum mechanics. A transition amplitude is represented as a sum over virtual paths which different intermediate measurements convert into different sets of real pathways.…

Quantum Physics · Physics 2009-11-13 D. Sokolovski , I. Puerto Gimenez , R. Sala Mayato

Manipulation of the refractive index has been of growing interest lately. We consider parameters and possibilities of enhancing the absolute-value limit of the linear index in coherent atomic systems. Starting with a review of how two-level…

Optics · Physics 2024-02-20 Robert A. McCutcheon , Susanne F. Yelin

We look afresh at the deduction of the "Lorentz contraction" of a "rod" from the Lorentz transformation equations of the special theory of relativity. We show that under special conditions, which include acceleration of the "rod", length…

General Physics · Physics 2009-04-14 Sadanand D Agashe