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Related papers: Divergences and Orientation in Spinfoams

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The present paper studies the large-j asymptotics of the Lorentzian EPRL spinfoam amplitude on a 4d simplicial complex with an arbitrary number of simplices. The asymptotics of the spinfoam amplitude is determined by the critical…

General Relativity and Quantum Cosmology · Physics 2013-07-24 Muxin Han , Mingyi Zhang

Spatially resolving two incoherent point sources whose separation is well below the diffraction limit dictated by classical optics has recently been shown possible using techniques that decompose the incoming radiation into orthogonal…

Quantum Physics · Physics 2021-02-10 J. O. de Almeida , J. Kołodyński , C. Hirche , M. Lewenstein , M. Skotiniotis

The simple reflection of a light beam of finite transverse extent from a homogenous interface gives rise to a surprisingly large number of subtle shifts and deflections which can be seen as diffractive corrections to the laws of geometrical…

Optics · Physics 2012-11-15 Jörg B Götte , Mark R Dennis

We study the semiclassical behavior of Lorentzian Engle-Pereira-Rovelli-Livine (EPRL) spinfoam model, by taking into account the sum over spins in the large spin regime. We also employ the method of stationary phase analysis with parameters…

General Relativity and Quantum Cosmology · Physics 2013-11-18 Muxin Han

We study two spiked models of random matrices under general frameworks corresponding respectively to additive deformation of random symmetric matrices and multiplicative perturbation of random covariance matrices. In both cases, the…

Probability · Mathematics 2020-10-14 Nathan Noiry

This paper is devoted to dimensional reductions via the norm resolvent convergence. We derive explicit bounds on the resolvent difference as well as spectral asymptotics. The efficiency of our abstract tool is demonstrated by its…

Mathematical Physics · Physics 2018-11-26 David Krejcirik , Nicolas Raymond , Julien Royer , Petr Siegl

Simplicial approaches to quantum gravity such as quantum Regge calculus and spin foams include configurations where bulk edges can become arbitrarily large while the boundary edges are kept small. Spikes and spines are prime examples for…

General Relativity and Quantum Cosmology · Physics 2024-10-24 Johanna Borissova , Bianca Dittrich , Dongxue Qu , Marc Schiffer

Off-axis parabolic mirrors (OAPs) are occasionally desirable for specialized applications, but are known to introduce field-dependent astigmatic aberrations. In an experiment where optical tweezers are formed by OAPs, another OAP is added…

Optics · Physics 2025-11-20 Meimei Liu , Yuqi Zhu , Giorgio Gratta

We study the semiclassical behavior of Lorentzian Engle-Pereira-Rovelli-Livine (EPRL) spinfoam model, by taking into account of the sum over spins in the large spin regime. The large spin parameter \lambda and small Barbero-Immirzi…

General Relativity and Quantum Cosmology · Physics 2013-09-09 Muxin Han

I compute the Lorentzian EPRL/FK/KKL spinfoam vertex amplitude for regular graphs, with an arbitrary number of links and nodes, and coherent states peaked on a homogeneous and isotropic geometry. This form of the amplitude can be applied…

General Relativity and Quantum Cosmology · Physics 2012-05-22 Francesca Vidotto

We observe fine structure in the resonance spectra of optical microcavities. We identify the polarization-resolved modes in the spectrum and find that resonance frequencies split in accordance with the theoretical prediction. The observed…

Optics · Physics 2022-06-15 C. Koks , F. B. Baalbergen , M. P. van Exter

It has previously been demonstrated in both simulation and experiment that well aligned remote focusing microscopes exhibit residual spherical aberration outside the focal plane. In this work, compensation of the residual spherical…

Optics · Physics 2023-05-17 Sharika Mohanan , Alexander D. Corbett

A strict analytical solution of the problem of spin-noise signal formation in a volume medium with randomly moving spin carriers is presented. The treatment is performed in the model of light scattering in a medium with fluctuating…

Optics · Physics 2018-02-07 G. G. Kozlov , I. I. Ryzhov , V. S. Zapasskii

We consider a diffusion equation in $\mathbb{R}^d$ with drift equal to the gradient of a homogeneous potential of degree $1+\gamma$, with $0<\gamma<1$, and local variance equal to $\varepsilon^2$ with $\varepsilon\to 0$. The associated…

Probability · Mathematics 2026-03-04 Paola Bermolen , Valeria Goicoechea , José R. León

Light injected into a spherical dielectric body may be confined very efficiently via the mechanism of total internal reflection. The frequencies that are most confined are called resonances. If the shape of the body deviates from the…

Optics · Physics 2020-09-30 Julius Gohsrich

Radio pulsar polarization exhibits a number of complex phenomena that are classified into the realm of `beyond the rotating vector model' (RVM). It is shown that these effects can be understood in geometrical terms, as a result of coherent…

High Energy Astrophysical Phenomena · Physics 2019-06-26 J. Dyks

Infrared divergence is a common feature of spinfoam models with a vanishing cosmological constant but is expected to disappear in presence of a non-vanishing cosmological constant. In this paper, we investigate the spinfoam amplitude with…

General Relativity and Quantum Cosmology · Physics 2024-05-24 Muxin Han , Qiaoyin Pan

We study the fundamental limits of detecting the presence of an additive rank-one perturbation, or spike, to a Wigner matrix. When the spike comes from a prior that is i.i.d. across coordinates, we prove that the log-likelihood ratio of the…

Probability · Mathematics 2020-06-11 Ahmed El Alaoui , Florent Krzakala , Michael I. Jordan

In this paper we introduce an optical approximation into the theory of impedance calculation, one valid in the limit of high frequencies. This approximation neglects diffraction effects in the radiation process, and is conceptually…

Accelerator Physics · Physics 2008-11-26 G. Stupakov , K. L. F. Bane , I. Zagorodnov

We conclude our analysis of bubble divergences in the flat spinfoam model. In [arXiv:1008.1476] we showed that the divergence degree of an arbitrary two-complex Gamma can be evaluated exactly by means of twisted cohomology. Here, we…

General Relativity and Quantum Cosmology · Physics 2012-02-03 Valentin Bonzom , Matteo Smerlak