cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Moving gravitational wave sources at cosmological distances: Impact on the measurement of the Hubble constant
Creators: name: Torres-Orjuela, Alejandro
name: Chen, Xian
Publisher: name: arXiv
Year: 2022
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Standard sirens - GW sources with an EM counterpart - can be used to measure H_0 directly which should help to ease the existing Hubble tension. However, if the source has a relative velocity to the expanding universe on top of its motion due to the Hubble flow, a relativistic redshift affects the redshift of the EM counterpart and the apparent distance of the GW source, and thus it needs to be corrected to obtain accurate measurements. We study the effect of such a relative velocity on GWs for a source in an expanding universe showing that the total redshift of the wave is equal to the product of the relativistic redshift and the cosmological redshift. We, further, find that a relative velocity of the source changes its apparent distance by a factor (1+z_rel)^2 in contrast to a linear factor for the cosmological redshift. We discuss that the additional factor for the relativistic redshift is a consequence of a velocity-dependent amplitude for GWs. We consider the effect of the relative velocity on the chirp mass and the apparent distance of the source an observer would infer when ignoring this velocity. We find that for different astrophysical scenarios the error can range between 0.1 % and 7 % for the chirp mass while the error in the apparent distance can be between 0.25 % and 15 %. Furthermore, we consider the error introduced in the measurement of H_0 using standard sirens for two cases: (i) when the effect of velocity on the redshift of the EM counterpart is considered but not on the apparent distance obtained from GWs and (ii) when the effect of the relative velocity is ignored completely. We find that in the first case the error can reach 1 % for a source moving due to the peculiar velocity of its host galaxy and that in the second case the error can be more than 5 % for a source at the distance of GW150914 with the same velocity.
description: 14 pages, 5 figures
${}^{3}\mathrm{He}$ and $pd$ Scattering to Next-to-Leading Order in Pionless Effective Field Theory
Creators: name: Vanasse, Jared
name: Egolf, David A.
name: Kerin, John
name: König, Sebastian
name: Springer, Roxanne P.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We study the three-body systems of ${}^{3}\mathrm{He}$ and $pd$ scattering and demonstrate, both analytically and numerically, that a new $pd$ three-body force is needed at next-to-leading order in pionless effective field theory. We also show that at leading order these observables require no new three-body force beyond what is necessary to describe $nd$ scattering. We include electromagnetic effects by iterating only diagrams that involve a single photon exchange in the three-body sector.
description: 41 pages, 12 figures
On-the-go Reflectance Transformation Imaging with Ordinary Smartphones
Creators: name: Pistellato, Mara
name: Bergamasco, Filippo
Publisher: name: arXiv
Year: 2022
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Graphics (cs.GR)
subject: FOS: Computer and information sciences

description: Reflectance Transformation Imaging (RTI) is a popular technique that allows the recovery of per-pixel reflectance information by capturing an object under different light conditions. This can be later used to reveal surface details and interactively relight the subject. Such process, however, typically requires dedicated hardware setups to recover the light direction from multiple locations, making the process tedious when performed outside the lab. We propose a novel RTI method that can be carried out by recording videos with two ordinary smartphones. The flash led-light of one device is used to illuminate the subject while the other captures the reflectance. Since the led is mounted close to the camera lenses, we can infer the light direction for thousands of images by freely moving the illuminating device while observing a fiducial marker surrounding the subject. To deal with such amount of data, we propose a neural relighting model that reconstructs object appearance for arbitrary light directions from extremely compact reflectance distribution data compressed via Principal Components Analysis (PCA). Experiments shows that the proposed technique can be easily performed on the field with a resulting RTI model that can outperform state-of-the-art approaches involving dedicated hardware setups.
description: VISART VI - Workshop at the European Conference of Computer Vision (ECCV)
Renormalization group flow to effective quantum mechanics at IR in an emergent dual holographic description for spontaneous chiral symmetry breaking
Creators: name: Kim, Ki-Seok
name: Nishida, Mitsuhiro
name: Choun, Yoonseok
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Implementing the Wilsonian renormalization group (RG) transformation in a nonperturbative way, we construct an effective holographic dual description with an emergent extradimension identified with an RG scale. Taking the large$-N$ limit, we obtain an equation of motion of an order-parameter field, here the chiral condensate for our explicit demonstration. In particular, an intertwined structure manifests between the first-order RG flow equations of renormalized coupling functions and the second-order differential equation of the order-parameter field, thus referred to as a nonperturbative RG-improved mean-field theory. Assuming translational symmetry as a vacuum state, we solve these nonlinear coupled mean-field equations based on a matching method between UV- and IR-regional solutions. As a result, we find an RG flow from a weakly-coupled chiral-symmetric UV fixed point to a strongly-correlated chiral-symmetry broken IR fixed point, where the renormalized velocity of Dirac fermions vanishes most rapidly and effective quantum mechanics appears at IR. Furthermore, we translate these RG flows of coupling functions into those of emergent metric tensors and extract out geometrical properties of the emergent holographic spacetime constructed from the UV- and IR-regional solutions. Surprisingly, we obtain the volume law of entanglement entropy in the Ryu-Takayanagi formula, which implies appearance of a black hole type solution in the limit of infinite cutoff even at zero temperature. We critically discuss our field theoretic interpretation for this solution in terms of potentially gapless multi-particle excitation spectra.
Revealing ultra-high-energy cosmic ray acceleration with multi-messenger observations of the nearby GRB 980425/SN 1998bw
Creators: name: Mirabal, Nestor
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: The origin of ultra-high energy cosmic rays (UHECRs) is one of the most mystifying issues in astroparticle physics. It has been suggested that gamma-ray bursts (GRBs) are excellent acceleration sites for cosmic rays. The propagation of UHECRs from the GRB host galaxy to the Earth should generate delayed secondary photons and neutrinos. Here we present a dedicated search for delayed UHECR and neutrino emission centered around the position of nearby GRB 980425/SN 1998bw. Located at a distance of 36.9 Mpc, GRB 980425/SN 1998bw is well within the Greisen-Zatsepin-Kuzmin (GZK) distance horizon. We find no evidence for UHECR or neutrino clustering around the GRB 980425/SN 1998bw position between 2004 and 2020. Under ideal propagation conditions, we propose that it might be possible to detect an excess from delayed UHECRs around GRB 980425/SN 1998bw within the next 100 years if the intergalactic magnetic field (IGMF) strength is $B \leq 3 \times 10^{-13}$ G.
description: 8 pages, 2 figures, revised version
Σημειωτική και μετάφραση: από τη σημείωση στη διασημειωτικότητα
Creators: name: Boklund-Λαγοπούλου, Κάριν
Publisher: name: Syn-Thèses
Year: 2022
Subjects: σημειωτική; μετάφραση; διασημειωτικότητα

description: Βιβλιοκρισία του συγγράμματος: Σημειωτική και μετάφραση: από τη σημείωση στη διασημειωτικότητα, του Ευάγγελου Κουρδή, Αθήνα, Εκδόσεις Ινστιτούτο του Βιβλίου–Καρδαμίτσα, 2020, 138 σελίδες, 14€, ISBN 9789603545118 (1η έκδοση)
description: Syn-Thèses, No 12 (2021): Νέες τάσεις στη μεταφρασεολογία: το ελληνικό παράδειγμα
Dynamics of the corotating vortices in dipolar Bose-Einstein condensates in the presence of dissipation
Creators: name: Gautam, S.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: We study the dynamics of a single and a corotating vortex pair in a dipolar Bose-Einstein condensate in the framework of dissipative Gross-Pitaevskii equation. This simple model enables us to simulate the effect of finite temperature on the vortex dynamics. We study the effect of dipolar interactions on the dynamics of a single vortex in the presence of phenomenological dissipation. In the case of a corotating vortex pair, an initial asymmetry in the locations of the vortices can lead to different decay rates for the constituent vortices as is the case for the condensates interacting via pure contact interactions. We observe that the anisotropic interaction between the component vortices manifests itself as the perceptible difference in the trajectories traversed by the vortices in the condensate at finite temperatures.
description: 8 pages, 7 figures
Dissociation slowdown by collective optical response under strong coupling conditions
Creators: name: Sukharev, Maxim
name: Subotnik, Joseph
name: Nitzan, Abraham
Publisher: name: arXiv
Year: 2022
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: Optics (physics.optics)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We consider an ensemble of diatomic molecules resonantly coupled to an optical cavity under strong coupling conditions at normal incidence. Photodissociation dynamics is examined via direct numerical integration of the coupled Maxwell-Schrodinger equations with molecular ro-vibrational degrees of freedom explicitly taken into account. It is shown that the dissociation is significantly affected (slowed down) when the system is driven at its polaritonic frequencies. The observed effect is demonstrated to be of transient nature and has no classical analog. An intuitive explanation of the dissociation slowdown at polaritonic frequencies is proposed.
Testing the accuracy of likelihoods for cluster abundance cosmology
Creators: name: Payerne, Constantin
name: Murray, Calum
name: Combet, Céline
name: Doux, Cyrille
name: Fumagalli, Alessandra
name: Penna-Lima, Mariana
Publisher: name: arXiv
Year: 2022
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: The abundance of galaxy clusters is a sensitive probe to the amplitude of matter density fluctuations, the total amount of matter in the Universe as well as its expansion history. Inferring correct values and accurate uncertainties of cosmological parameters requires accurate knowledge of cluster abundance statistics, encoded in the likelihood function. In this paper, we test the accuracy of cluster abundance likelihoods used in the literature, namely the Poisson and Gaussian likelihoods as well as the more complete description of the Gauss-Poisson Compound likelihood. This is repeated for a variety of binning choices and analysis setups. In order to evaluate the accuracy of a given likelihood, this work compares individual posterior covariances to the covariance of estimators over the 1000 simulated dark matter halo catalogs obtained from PINOCCHIO algorithm. We find that for Rubin/LSST or Euclid-like surveys the Gaussian likelihood gives robust constraints over a large range of binning choices. The Poisson likelihood, that does not account for sample covariance, always underestimates the errors on the parameters, even when the sample volume is reduced or only high-mass clusters are considered. We find no benefit in using the more complex Gauss-Poisson Compound likelihood as it gives essentially the same results as the Gaussian likelihood, but at a greater computational cost. Finally, in this ideal setup, we note only a small gain on the parameter error bars when using a large number of bins in the mass-redshift plane.
description: 13 pages, 10 figures, accepted for publication in MNRAS
Possible generation of anomalously soft quark excitations at nonzero temperature: Nonhyperbolic dispersion of parapion and van Hove singularity
Creators: name: Kitazawa, Masakiyo
name: Kunihiro, Teiji
name: Nemoto, Yukio
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We study the quark spectrum at finite temperature near and above the pseudocritical temperature of the chiral phase transition incorporating the effects of the collective modes with the quantum number of the sigma (parasigma) and pion (parapion) in a chiral effective model with a nonzero current quark mass. Below the pion zero-binding temperature where the pionic modes are bound, the quark self-energy has van Hove singularity induced by the scattering of quarks with the composite bound pions with a nonhyperbolic dispersion curve. This singularity is found to cause a drastic change in the quark spectrum from that in the mean field picture near the pseudocritical temperature: The quark spectrum has an unexpected sharp peak at an energy considerably lower than the constituent quark mass, while the spectrum approaches the mean field one at high temperatures. We clarify that the emergence of this anomalous structure of the quark spectral function originates from the composite nature of the pionic modes with a non-Lorentz invariant dispersion relation in the medium at finite temperature.
description: 10 pages, 7 figures, to appear in Phys. Rev. D. Comments on the parameter dependence, the Matsubara summation, future prospects added. References added. Typos corrected
From scale invariance to Lorentz symmetry
Creators: name: Sibiryakov, Sergey
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: It is shown that a unitary translationally invariant field theory in (1+1) dimensions satisfying isotropic scale invariance, standard assumptions about the spectrum of states and operators and the requirement that signals propagate with finite velocity possesses an infinite dimensional symmetry given by one or a product of several copies of conformal algebra. In particular, this implies presence of one or several Lorentz groups acting on the operator algebra of the theory.
description: 5 pages, no figures; changes in the abstract
Properties of scalar wave emission in a scalar-tensor theory with kinetic screening
Creators: name: Shibata, Masaru
name: Traykova, Dina
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We study numerically the scalar wave emission by a non-spherical oscillation of neutron stars in a scalar-tensor theory of gravity with kinetic screening, considering both the monopole and quadrupole mode emission. In agreement with previous results in the literature, we find that the monopole is always suppressed by the screening effect, regardless of the size of the screening radius, $r_{\rm sc}$. For the quadrupole mode, however, our analysis shows that the suppression only occurs for screening radius larger than the wavelength of scalar waves, $λ_{\rm wave}$, but not for $r_{\rm sc} < λ_{\rm wave}$. This demonstrates that to fully understand the nature of this theory, it is necessary to study other more complex systems, such as neutron star binaries, considering a wide range of $r_{\rm sc}$ values.
description: 13 pages, 8 figures; Minor changes, version as accepted in PRD
Εισαγωγή: το ελληνικό παράδειγμα στη μεταφρασεολογία
Creators: name: Χαραλαμπίδου, Παρθένα
name: Κουρδής, Ευάγγελος
Publisher: name: Syn-Thèses
Year: 2022
Subjects: ελληνόφωνη μεταφρασεολογία; ελληνικό παράδειγμα

description: ----
description: Syn-Thèses, No 12 (2021): Νέες τάσεις στη μεταφρασεολογία: το ελληνικό παράδειγμα
Multiple Lac-mediated loops revealed by Bayesian statistics and tethered particle motion
Creators: name: Johnson, Stephanie
name: van de Meent, Jan-Willem
name: Phillips, Rob
name: Wiggins, Chris H.
name: Lindén, Martin
Publisher: name: arXiv
Year: 2014
Subjects: subject: Biological Physics (physics.bio-ph)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: Biomolecules (q-bio.BM)
subject: FOS: Physical sciences
subject: FOS: Biological sciences

description: The bacterial transcription factor LacI loops DNA by binding to two separate locations on the DNA simultaneously. Despite being one of the best-studied model systems for transcriptional regulation, the number and conformations of loop structures accessible to LacI remain unclear, though the importance of multiple co-existing loops has been implicated in interactions between LacI and other cellular regulators of gene expression. To probe this issue, we have developed a new analysis method for tethered particle motion, a versatile and commonly-used in vitro single-molecule technique. Our method, vbTPM, performs variational Bayesian inference in hidden Markov models. It learns the number of distinct states (i.e., DNA-protein conformations) directly from tethered particle motion data with better resolution than existing methods, while easily correcting for common experimental artifacts. Studying short (roughly 100 bp) LacI-mediated loops, we provide evidence for three distinct loop structures, more than previously reported in single-molecule studies. Moreover, our results confirm that changes in LacI conformation and DNA binding topology both contribute to the repertoire of LacI-mediated loops formed in vitro, and provide qualitatively new input for models of looping and transcriptional regulation. We expect vbTPM to be broadly useful for probing complex protein-nucleic acid interactions.
description: 34 pages, 25 figures, including Supporting information. To appear in Nucleic Acids Research. Accompanying open-source software: http://sourceforge.net/projects/vbtpm/
Accessing gluon polarization with high-$P_T$ hadrons in SIDIS
Creators: name: Whitehill, R. M.
name: Zhou, Yiyu
name: Sato, N.
name: Melnitchouk, W.
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: A recent global QCD analysis of jet production and other polarized scattering data has found the presence of negative solutions for the gluon helicity distribution in the proton, $Δg$, along with the traditional $Δg > 0$ solutions. We consider polarized semi-inclusive deep-inelastic scattering for hadrons produced with large transverse momentum as a means of constraining the dependence of $Δg$ on the parton momentum fraction, $x$. Focusing on the double longitudinal spin asymmetry, we identify the kinematics relevant for future experiments at Jefferson Lab and the Electron-Ion Collider which are particularly sensitive to the polarized gluon channel and could discriminate between the different $Δg$ behaviors.
description: 22 pages, 7 figures
Optimized shooting method for finding periodic orbits of nonlinear dynamical systems
Creators: name: Dednam, W.
name: Botha, A. E.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Chaotic Dynamics (nlin.CD)
subject: FOS: Physical sciences
subject: 34B15, 34C25, 35B10, 49N20, 70K42

description: An alternative numerical method is developed to find stable and unstable periodic orbits of nonlinear dynamical systems. The method exploits the high-efficiency of the Levenberg-Marquardt algorithm for medium-sized problems and has the additional advantage of being relatively simple to implement. It is also applicable to both autonomous and non-autonomous systems. As an example of its use, it is employed to find periodic orbits in the Rössler system, a coupled Rössler system, as well as an eight-dimensional model of a flexible rotor-bearing; problems which have been treated previously via two related methods. The results agree with the previous methods and are seen to be more accurate in some cases. A simple implementation of the method, written in the Python programming language, is provided as an Appendix.
description: 21 pages, 7 figures
Localization properties of harmonic chains with correlated mass and spring disorder: Analytical approach
Creators: name: Herrera-Gonzalez, I. F.
name: Mendez-Bermudez, J. A.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: We study the localization properties of normal modes in harmonic chains with mass and spring weak disorder. Using a perturbative approach, an expression for the localization length is obtained, which is valid for arbitrary correlations of the disorder, and for practically the whole frequency band. In addition, we show how to generate effective mobility edges by the use of disorder with long range self-correlations and cross-correlations. Finally, the transport of phonons is also analyzed showing effective transparent windows that can be manipulated through the disorder correlations even for relative short chain sizes. Our results may have applications in modulating thermal transport, particularly in the design of thermal filters or in manufacturing high-thermal-conductivity materials.
description: 10 pages, 6 figures
Cardy-Verlinde Formula of Non-Commutative Schwarzschild Black Hole
Creators: name: Abbas, G.
Publisher: name: arXiv
Year: 2014
Subjects: subject: General Physics (physics.gen-ph)
subject: FOS: Physical sciences

description: Few years ago, Setare \cite{1} has investigated the Cardy-Verlinde formula of non-commutative black hole obtained by non-commutativity of coordinates. In this paper, we apply the same procedure to a non-commutative black hole obtained by the co-ordinate coherent approch. The Cardy-Verlinde formula is entropy formula of conformal field theory in an arbitrary dimension. It relates the entropy of conformal filed theory to its total energy and Casimir energy. In this paper, we have calculated the total energy and Casimir energy of non-commutative Schwarzschild black hole and have shown that entropy of non-commutative Schwarzschild black hole horizon can be expressed in terms of Cardy-Verlinde formula.
description: 9 Pages, no figures, Accepted for Publication in Advances in High Energy Physics. Some typos removed
Supersymmetric non-Hermitian topological interface laser
Creators: name: Ezawa, Motohiko
name: Ishida, Natsuko
name: Ota, Yasutomo
name: Iwamoto, Satoshi
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We investigate laser emission at the interface of a topological and trivial phases with loss and gain. The system is described by a Su-Schrieffer-Heeger model with site-dependent hopping parameters. We study numerically and analytically the interface states. The ground state is described by the Jackiw-Rebbi mode with a pure imaginary energy, reflecting the non-Hermiticity of the system. It is strictly localized only at the A sites. We also find a series of analytic solutions of excited states based on SUSY quantum mechanics, where the A and B sites of the bipartite lattice form SUSY partners. We then study the system containing loss and gain with saturation. The Jackiw-Rebbi mode is extended to a nonlinear theory, where B sites are also excited. The relative phases between A and B sites are fixed, and hence it will serve as a large area coherent laser.
description: 11 pages, 7 pages
Decay Constants of Pseudoscalar $D$-mesons in Lattice QCD with Domain-Wall Fermion
Creators: name: Chen, Wen-Ping
name: Chen, Yu-Chih
name: Chiu, Ting-Wai
name: Chou, Han-Yi
name: Guu, Tian-Shin
name: Hsieh, Tung-Han
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Experiment (hep-ex)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We present the first study of the masses and decay constants of the pseudoscalar $ D $ mesons in two flavors lattice QCD with domain-wall fermion. The gauge ensembles are generated on the $24^3 \times 48 $ lattice with the extent $ N_s = 16 $ in the fifth dimension, and the plaquette gauge action at $ β= 6.10 $, for three sea-quark masses with corresponding pion masses in the range $260-475$ MeV. We compute the point-to-point quark propagators, and measure the time-correlation functions of the pseudoscalar and vector mesons. The inverse lattice spacing is determined by the Wilson flow, while the strange and the charm quark masses by the masses of the vector mesons $ ϕ(1020) $ and $ J/ψ(3097) $ respectively. Using heavy meson chiral perturbation theory (HMChPT) to extrapolate to the physical pion mass, we obtain $ f_D = 202.3(2.2)(2.6) $ MeV and $ f_{D_s} = 258.7(1.1)(2.9) $ MeV.
description: 15 pages, 3 figures. v2: the statistics of ensemble (A) with m_sea = 0.005 has been increased, more details on the systematic error, to appear in Phys. Lett. B
Three dimensional full-field velocity measurements in shock compression experiments using stereo digital image correlation
Creators: name: Ravindran, Suraj
name: Gandhi, Vatsa
name: Joshi, Akshay
name: Ravichandran, Guruswami
Publisher: name: arXiv
Year: 2022
Subjects: subject: Applied Physics (physics.app-ph)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: Shock compression plate impact experiments conventionally rely on point-wise velocimetry measurements based on laser-based interferometric techniques. This study presents an experimental methodology to measure the free surface full-field particle velocity in shock compression experiments using high-speed imaging and three-dimensional (3D) digital image correlation (DIC). The experimental setup has a temporal resolution of 100 ns with a spatial resolution varying from 90 to 200 $μ$m/pixel. Experiments were conducted under three different plate impact configurations to measure spatially resolved free surface velocity and validate the experimental technique. First, a normal impact experiment was conducted on polycarbonate to measure the macroscopic full-field normal free surface velocity. Second, an isentropic compression experiment on Y-cut quartz-tungsten carbide assembly is performed to measure the particle velocity for experiments involving ramp compression waves. To explore the capability of the technique in multi-axial loading conditions, a pressure shear plate impact experiment was conducted to measure both the normal and transverse free surface velocities under combined normal and shear loading. The velocities measured in the experiments using digital image correlation are validated against previous data obtained from laser interferometry. Numerical simulations were also performed using established material models to compare and validate the experimental velocity profiles for these different impact configurations. The novel ability of the employed experimental setup to measure full-field free surface velocities with high spatial resolutions in shock compression experiments is demonstrated for the first time in this work.
description: The first two authors contributed equally to this work
Worldline holographic Schwinger effect
Creators: name: Dietrich, Dennis D.
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: The decay of the vacuum due to the presence of an electric field is expected to be delayed by a confining force. We demonstrate that this feature is captured by our model [arXiv:1404.0011 [hep-ph],arXiv:1312.5718 [hep-ph]] for hadrons based on the worldline formalism. Our model, while based entirely in four-dimensional quantum field theory, shares many features with holographic approaches: it appears intrinsically quantum mechanical; as an auxiliary fifth dimension Schwinger's proper time combines with the physical four spacetime dimensions into an AdS$_5$ geometry; conformal-symmetry breaking contributions lead to warping; hidden local symmetry emerges; four-dimensional sources are extended to five-dimensional fields by a Wilson flow (gradient flow); and a variational principle for this flow reproduces the corresponding holographic calculation. The approach also yields the higher-dimensional description in the non-relativistic case.
description: 11 pages, 1 figure; v2 matches published version
Tidally excited gravity waves in the cores of solar-type stars: resonances and critical-layer formation
Creators: name: Guo, Zhao
name: Ogilvie, Gordon I.
name: Barker, Adrian J.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We simulate the propagation and dissipation of tidally induced nonlinear gravity waves in the cores of solar-type stars. We perform hydrodynamical simulations of a previously developed Boussinesq model using a spectral-element code to study the stellar core as a wave cavity that is periodically forced at the outer boundary with a given azimuthal wavenumber and an adjustable frequency. For low-amplitude forcing, the system exhibits resonances with standing g-modes at particular frequencies, corresponding to a situation in which the tidal torque is highly frequency-dependent. For high-amplitude forcing, the excited waves break promptly near the centre and spin up the core so that subsequent waves are absorbed in an expanding critical layer, as found in previous work, leading to a tidal torque with a smooth frequency-dependence. For intermediate-amplitude forcing, we find that linear damping of the waves gradually spins up the core such that the resonance condition can be altered drastically. The system can evolve towards or away from g-mode resonances, depending on the difference between the forcing frequency and the closest eigenfrequency. Eventually, a critical layer forms and absorbs the incoming waves, leading to a situation similar to the high-amplitude case in which the waves break promptly. We study the dependence of this process on the forcing amplitude and frequency, as well as on the diffusion coefficients. We emphasize that the small Prandtl number in the centre of solar-like stars facilitates the development of a differentially rotating core owing to the nonlinear feedback of waves. Our simulations and analysis reveal that this important mechanism may drastically change the phase of gravity waves and thus the classical picture of resonance locking in solar-type stars needs to be revised.
description: 22 pages, 26 figures, MNRAS accepted, comments welcome
SmB6 Photoemission: Past and Present
Creators: name: Denlinger, Jonathan D.
name: Allen, James W.
name: Kang, Jeong-Soo
name: Sun, Kai
name: Min, Byung-Il
name: Kim, Dae-Jeong
name: Fisk, Zachary
Publisher: name: arXiv
Year: 2013
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Recent renewed interest in the mixed valent insulator SmB6 comes from topological theory predictions and surface transport measurements of possible in-gap surface states whose existence is most directly probed by angle-resolved photoemission spectroscopy (ARPES). Early photoemission leading up to a recent flurry of ARPES studies of in-gap states is reviewed. Conflicting interpretations about the nature of the Sm 4f-5d hybridization gap and observed X-point bands between the f-states and the Fermi level are critically assessed using the important tools of photon polarization and spatial dependence which also provide additional insight into the origin of the more ambiguous Γ-point in-gap states.
description: 10 pages, 6 figures, SCES2013 proceedings; references updated
André-Marie AMPERE (1775-1836), le génie et les larmes
Creators: name: Dufour, Xavier
Publisher: name: SEE
Year: 2021

description: La célébration des fulgurantes découvertes d’André-Marie Ampère, réalisées en septembre 1820 dans le domaine de l’électromagnétisme, ne doit pas occulter les multiples facettes d’un autodidacte génial, à la jonction de l’Encyclopédie et du romantisme. Officiellement mathématicien, volontiers chimiste, à l’occasion naturaliste mais toujours philosophe, Ampère fut aussi un homme de cœur, sensible et mystique, dont la vie fut marquée par de cruelles épreuves.
La lumière - Une histoire d’amitié entre Fresnel et Ampère
Creators: name: Amouyal, Edmond
Publisher: name: SEE
Year: 2021

description: La théorie ondulatoire de la lumière d’Augustin Fresnel et celle de l’électrodynamique d’André-Marie Ampère, sont les fruits d’une véritable collaboration -peu connue- entre deux savants fidèles en amitié, généreux et géniaux. Elles constituent deux des plus grandes découvertes du XIXème siècle, à l’origine du formidable essor de la recherche et de l’innovation industrielle.
A Transfer Operator Approach to Relativistic Quantum Wavefunction
Creators: name: Mezic, Igor
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: The original intent of the Koopman-von Neumann formalism was to put classical and quantum mechanics on the same footing by introducing an operator formalism into classical mechanics. Here we pursue their path the opposite way and examine what transfer operators can say about quantum mechanical evolution. To that end, we introduce a physically motivated scalar wavefunction formalism for a velocity field on a 4-dimensional pseudo-Riemannian manifold, and obtain an evolution equation for the associated wavefunction, a generator for an associated weighted transfer operator. The generator of the scalar evolution is of first order in space and time. The probability interpretation of the formalism leads to recovery of the Schrodinger equation in the non-relativistic limit. In the special relativity limit, we show that the scalar wavefunction of Dirac spinors satisfies the new equation. A connection with string theoretic considerations for mass is provided.
Diálogos y aleaciones experimentales. Prácticas lectoras en clave interseccional y post-colonial: por el derecho a la diferencia y la reinvención de la ciudadanía cultural
Creators: name: González, Aldo Ocampo
Publisher: name: figshare
Year: 2020
Subjects: Education

description: Quisiera inaugurar este manuscrito retomando algunas de las principales interrogantes críticas que vertebraron los supuestos y conceptos-problemas de trabajo de la versión inaugural del Coloquio Internacional sobre Prácticas lectoras en clave interseccional y post-colonial: por el derecho a la diferencia y la reinvención de la ciudadanía cultural, celebrado el viernes 10 de enero de 2020, en la ciudad de Santiago de Chile. ¿Por qué iniciar un texto a partir de interrogantes críticas? Lo primero es destacar la sección de la pregunta referida a ‘lo crítico’, operación que manifiesta la insistencia impulsada por Foucault (1985), y, posteriormente, retomada por Butler (2002), en torno al sentido y alcance de la crítica, concebida como una fuerza intensamente creativa cuya capacidad permite escuchar para enunciar entre signos de interrogación aquello que es recetado por este singular terreno de estudio en torno al alfabetismos, el derecho a la lectura y a las prácticas letradas. La crítica enfrenta una posición contingente que no se reduce al orden de una posición y de una práctica genérica sobre determinados objetos, lo cierto es que, “la crítica es siempre crítica de alguna práctica, discurso, episteme o institución instituidas, y pierde su carácter en el momento en que se abstrae de esta forma de operar y se la aísla como una práctica puramente generalizable” (Butler, 2002, p.1).
Matrix products with constraints on the sliding block relative frequencies of different factors
Creators: name: Kozyakin, Victor
Publisher: name: arXiv
Year: 2014
Subjects: subject: Rings and Algebras (math.RA)
subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics
subject: 15A18, 15A60, 37B10, 60J10

description: One of fundamental results of the theory of joint/generalized spectral radius, the Berger-Wang theorem, establishes equality between the joint and generalized spectral radii of a set of matrices. Generalization of this theorem on products of matrices whose factors are applied not arbitrarily but are subjected to some constraints is connected with essential difficulties since known proofs of the Berger-Wang theorem rely on the arbitrariness of appearance of different matrices in the related matrix products. Recently, X. Dai proved an analog of the Berger-Wang theorem for the case when factors in matrix products are formed by some Markov law. We introduce the concepts of the joint and generalized spectral radii for products of matrices subjected to constraints on the sliding block relative frequencies of occurrences of different matrices, and prove an analog of the Berger-Wang theorem for this case.
description: 15 pages, 25 bibliography references, updated notation, in press in Linear Algebra and Its Applications
L’unité ampère : de l’électrodynamique à la mécanique quantique
Creators: name: Poirier, Wilfrid
Publisher: name: SEE
Year: 2021

description: L’auteur retrace l’histoire complexe et mouvementée des unités électriques depuis l’adoption du système métrique jusqu’à la révision historique du Système International d’unités (SI) adoptée en 2018.
Œrsted, un précurseur de l’électromagnétisme
Creators: name: Zwisler, Laila
Publisher: name: SEE
Year: 2021

description: En 1820, le savant danois Hans Christian Œrsted découvre un phénomène nouveau pendant un cours en faisant passer un courant électrique au-dessus d’une boussole. Il observe que le courant provoque une légère déviation de l’aiguille aimantée. Œrsted mettait ainsi évidence un lien entre l’électricité et le magnétisme, un effet connu par la suite sous le nom d’électromagnétisme.
On the development of a new coplanar transmission line based on Gap Waveguide
Creators: name: Biurrun-Quel, Carlos
name: Teniente, Jorge
name: del-Rio, Carlos
Publisher: name: arXiv
Year: 2022
Subjects: subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: A combination of gap waveguide technology and the traditional coplanar waveguide is studied in detail and demonstrated experimentally for the first time. This novel metamaterial transmission line is presented in three different configurations and offers a broadband operation, low loss, and low dispersion characteristics. Analytical expressions for its characteristic impedance and effective permittivity are provided and validated by Finite Element Method simulations. The loss and dispersion of the line are analyzed with an Eigenmode solver. The proposed line prevents the propagation of substrate modes in the band of operation at the same time it reduces the dielectric loss in the line due to a higher concentration of the E-field over the air. Moreover, its coplanar layout facilitates the integration of active components. As such, it is considered to constitute a potential key element in the development of more efficient, millimeter wave systems.
description: To be submitted to MDPI Sensors
Planet X revamped after the discovery of the Sedna-like object 2012 VP$_{113}$?
Creators: name: Iorio, Lorenzo
Publisher: name: arXiv
Year: 2014
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: The recent discovery of the Sedna-like dwarf planet 2012 VP$_{\rm 113}$ by Trujillo and Sheppard has revamped the old-fashioned hypothesis that a still unseen trans-Plutonian object of planetary size, variously dubbed over the years as Planet X, Tyche, Thelisto, may lurk in the distant peripheries of the Solar System. This time, the presence of a super-Earth with mass $m_{\rm X} = 2-15m_{\oplus}$ at a distance $d_{\rm X}\approx 200-300$ astronomical units (AU) was proposed to explain the observed clustering of the arguments of perihelion $ω$ near $ω\approx 0^{\circ}$ but not $ω\approx 180^{\circ}$ for Sedna, 2012 VP$_{\rm 113}$ and other minor bodies of the Solar System with perihelion distances $q>30$ AU and semimajor axes $a>150$ AU. Actually, such a scenario is strongly disfavored by the latest constraints $Δ\dot\varpi$ on the anomalous perihelion precessions of some Solar System's planets obtained with the INPOP and EPM ephemerides. Indeed, they yield $d_{\rm X}\gtrsim 496-570$ AU ($m_{\rm X}=2m_{\oplus}$), and $d_{\rm X}\gtrsim 970-1111$ AU ($m_{\rm X} = 15 m_{\oplus}$). Much tighter constraints could be obtained in the near future from the New Horizons mission to Pluto.
description: LaTex2e, 2 pages, no figures, no tables. Accepted for publication in Monthly Notices of the Royal Astronomical Society Letters (MNRAS Letters)
title: Οξειδωτικό Στρες, Άσκηση και Αισθητικά Προβλήματα
title: Oxidative Stress, Exercise and Aesthetic Problems
titleType: AlternativeTitle
Creators: name: Βασιλάκη, Ευαγγελία
Publisher: name: Πανεπιστήμιο Δυτικής Αττικής
Year: 2022
Subjects: Οξειδωτικό στρες
Αντιοξειδωτικά
Άσκηση
Αισθητικά προβλήματα
Ελεύθερες ρίζες

description: Η εργασία αυτή μελέτησε το οξειδωτικό στρες, τα αισθητικά προβλήματα που μπορεί να προκαλέσει καθώς και το ρόλο της άσκησης στην εκδήλωση του. Το οξειδωτικό στρες είναι επιβλαβές για την ανθρώπινη υγεία και παίζει σημαντικό ρόλο στην παθογένεση δυνητικά σοβαρών καταστάσεων. Προκαλείται από αντιδραστικά είδη οξυγόνου μπορεί να είναι υπαίτιο για εκδήλωση πιτυρίδας, σμηγματορροϊκής δερματίτιδας, ψωρίασης, ατοπικής δερματίτιδας καθώς και αλωπεκίας. Το οξειδωτικό στρες παίζει επίσης σημαντικό ρόλο στη διαδικασία της γήρανσης του ανθρώπινου δέρματος. Οι περιβαλλοντικοί ρύποι, το διοξείδιο του αζώτου και το όζον προκαλούν επιβλαβείς επιδράσεις μέσω των αντιδράσεων των ελεύθερων ριζών που επιτυγχάνονται είτε απευθείας με οξείδωση βιομορίων για τη δημιουργία ROS είτε με παραγωγή κυτταροτοξικών μη ριζικών μορίων. Μελέτες έδειξαν ότι η χρόνια έκθεση σε αυτά τα σωματίδια συσχετίστηκε σημαντικά με σημάδια εξωτερικής γήρανσης, ιδιαίτερα με χρωστικές κηλίδες και πιο έντονες ρινοπαρειακές πτυχές. Επιπλέον, έχει αποδειχθεί ότι η τοπική εφαρμογή των αντιοξειδωτικών βιταμίνης C και Ε μπορεί να αποτρέψει το σχηματισμό προϊόντων οξείδωσης, μειώνοντας έτσι την οξειδωτική βλάβη στο δέρμα που προκαλείται από το περιβάλλον. Η διατροφή και τα εξωγενή αντιοξειδωτικά συμπληρώματα μπορεί να έχουν δυνητικό ρόλο στην καταπολέμηση του οξειδωτικού στρες που προκαλείται ως αποτέλεσμα περιβαλλοντικών παραγόντων. Η άσκηση αυξάνει την παραγωγή ελεύθερων ριζών. Έχει διαπιστωθεί ότι η τακτική άσκηση με ελαφριά έως μέτρια ένταση θα μπορούσε σταδιακά να ενισχύσει τον ενδογενή αντιοξειδωτικό αμυντικό μηχανισμό και να μειώσει το επίπεδο του οξειδωτικού στρες. Αντίθετα, η οξεία άσκηση και η άσκηση υψηλής έντασης οδηγούν σε αυξημένο επίπεδο οξειδωτικού στρες. Τέλος, η μέτριας έντασης άσκηση μπορεί να βελτιώσει την ελαστικότητα και την ενυδάτωση του δέρματος, και να βελτιώσει την κυτταρίτιδα. Ωστόσο, η έντονη άσκηση μπορεί να οδηγήσει σε δερματικά προβλήματα και αλωπεκία.
Probing atomic environments in alloys by electron spectroscopy
Creators: name: Underwood, T. L.
name: Ackland, G. J.
name: Cole, R. J.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: In alloys exhibiting substitutional disorder, the variety of atomic environments manifests itself as a `disorder broadening' in their core level binding energy spectra. Disorder broadening can be measured experimentally, and in principle can be used to deduce information about specific atomic environments within a sample. However, progress in this endeavor is hampered by the lack of a model for this phenomenon which can treat complex systems. In this work we describe such a model. The model is used to elucidate the relationship between charge transfer, atomic environment, and disorder broadening in complex systems, with a focus on the problem of characterizing the interface quality of CuNi multilayers. We also validate the model against the results of ab initio electronic structure calculations. Several counterintuitive aspects of the disorder broadening phenomenon are uncovered, an understanding of which is essential for the correct interpretation of experimental results. For instance, it is shown that systems with inhomogeneous concentration profiles can exhibit disorder broadenings significantly larger than random alloys. Furthermore in some systems a `disorder narrowing' is even possible.
Développer le réseau de transport pour la transition énergétique
Médaille Ampère
Creators: name: Houry, Marie-Pierre
Publisher: name: SEE
Year: 2021

description: De nombreuses transformations du mix énergétique sont à prévoir dans les décennies à venir tant en France qu’en Europe. Le réseau de transport d’électricité, maillon essentiel du système électrique, va devoir se développer. Cet article fait le point sur les méthodes et outils de planification du réseau utilisés dans un contexte énergétique incertain. La médaille Ampère est une distinction attribuée à une personne ayant particulièrement œuvré au profit de la SEE dans les domaines scientifiques de l’électricité, de l’électronique, et des technologies de l’information et de la communication. L’année 2020, départ de de la commémoration d’Ampère 200 ans par la SEE, a été marquée par l’attribution exceptionnelle de deux médailles Ampère dont celle décernée à Mme Houry.