cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
On signatures of spontaneous collapse dynamics modified single field inflation
Creators: name: Banerjee, Shreya
name: Das, Suratna
name: Kumar, K. Sravan
name: Singh, T. P.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The observed classicality of primordial perturbations, despite their quantum origin during inflation, calls for a mechanism for quantum-to-classical transition of these initial fluctuations. As literature suggests a number of plausible mechanisms which try to address this issue, it is of importance to seek for concrete observational signatures of these several approaches in order to have a better understanding of the early universe dynamics. Among these several approaches, it is the spontaneous collapse dynamics of Quantum Mechanics which is most viable of leaving discrete observational signatures as collapse mechanism inherently changes the generic Quantum dynamics. We observe in this study that the observables from the scalar sector, i.e. scalar tilt $n_s$, running of scalar tilt $α_s$ and running of running of scalar tilt $β_s$, can not potentially distinguish a collapse modified inflationary dynamics in the realm of canonical scalar field and $k-$inflationary scenarios. The only distinguishable imprint of collapse mechanism lies in the observables of tensor sector in the form of modified consistency relation and a blue-tilted tensor spectrum only when the collapse parameter $δ$ is non-zero and positive.
description: 14 pg, 2 tables, 0 figs, v2: Version accepted for publication on Phys. Rev. D. Title of the paper modified slightly
Quantum limited measurement of space-time curvature with scaling beyond the conventional Heisenberg limit
Creators: name: Kish, Sebastian P.
name: Ralph, Timothy C.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We study the problem of estimating the phase shift due to the general relativistic time dilation in the interference of photons using a non-linear Mach-Zender interferometer setup. By introducing two non-linear Kerr materials, one in the bottom and one in the top arm, we can measure the non-linear phase $ϕ_{NL}$ produced by the space-time curvature and achieve a scaling of the standard deviation with photon number ($N$) of $1/N^β$ where $β> 1$, which exceeds the conventional Heisenberg limit of a linear interferometer ($1/N$). The non-linear phase shift is an effect that is amplified by the intensity of the probe field. In a regime of high number of photons, this effect can dominate over the linear phase shift.
description: 8 pages, 4 figures, Closest to published version
Hypercuboidal renormalization in spin foam quantum gravity
Creators: name: Bahr, Benjamin
name: Steinhaus, Sebastian
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In this article we apply background-independent renormalization group methods to spin foam quantum gravity. It is aimed at extending and elucidating the analysis of a companion letter, in which the existence of a fixed point in the truncated RG flow for the model was reported. Here we repeat the analysis with various modifications, and find that both qualitative and quantitative features of the fixed point are robust in this setting. We also go into details about the various approximation schemes employed in the analysis.
description: 14 + 4 pages, 18 figures, v2: matching published version, minor improvements and updated references
$D \to ρ\,\ell^+\ell^-$ Decays in the QCD Factorization Approach
Creators: name: Feldmann, Thorsten
name: Mueller, Bastian
name: Seidel, Dirk
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We consider rare semileptonic decays of a heavy $D$-meson into a light vector meson in the framework of QCD factorization. In contrast to the corresponding $B$-meson decays, the naive factorization hypothesis does not even serve as a first approximation. Rather, the decay amplitudes appear to be dominated by non-factorizable dynamics, e.g. through annihilation topologies, which are particularly sensitive to long-distance hadronic contributions. We therefore pay particular attention to intermediate vector-meson resonances appearing in quark-loop and annihilation topologies. Compared to the analogous $B$-meson decays, we identify a number of effects that result in very large theoretical uncertainties for differential decay rates. Some of these effects are found to cancel in the ratio of partially integrated decay rates for transversely and longitudinally polarized $ρ$ mesons. On the phenomenological side this implies a very limited potential to constrain physics beyond the Standard Model by means of these decays.
description: 40 pages, 12 figures, minor text changes, minor bug in numerical output fixed, conclusions unchanged
Empirical analysis and agent-based modeling of Lithuanian parliamentary elections
Creators: name: Kononovicius, A.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Physics and Society (physics.soc-ph)
subject: FOS: Physical sciences

description: In this contribution we analyze a parties' vote share distribution across the polling stations during the Lithuanian parliamentary elections of 1992, 2008 and 2012. We find that the distribution is rather well fitted by the Beta distribution. To reproduce this empirical observation we propose a simple multi-state agent-based model of the voting behavior. In the proposed model agents change the party they vote for either idiosyncratically or due to a linear recruitment mechanism. We use the model to reproduce the vote share distribution observed during the election of 1992. We discuss model extensions needed to reproduce the vote share distribution observed during the other elections.
description: 19 pages, 11 figures
Momentum conserving defects in affine Toda field theories
Creators: name: Bristow, Rebecca
name: Bowcock, Peter
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: Type II integrable defects with more than one degree of freedom at the defect are investigated. A condition on the form of the Lagrangian for such defects is found which ensures the existence of a conserved momentum in the presence of the defect. In addition it is shown that for any Lagrangian satisfying this condition, the defect equations of motion, when taken to hold everywhere, can be extended to give a Bäcklund transformation between the bulk theories on either side of the defect. This strongly suggests that such systems are integrable. Momentum conserving defects and Bäcklund transformations for affine Toda field theories based on the $A_n$, $B_n$, $C_n$ and $D_n$ series of Lie algebras are found. The defect associated with the $D_4$ affine Toda field theory is examined in more detail. In particular classical time delays for solitons passing through the defect are calculated.
description: 26 pages, typos corrected and a reference removed
Entropy of a box of gas in an external gravitational field $-$ revisited
Creators: name: Bhattacharya, Sourav
name: Chakraborty, Sumanta
name: Padmanabhan, T.
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Earlier it was shown that the entropy of an ideal gas, contained in a box and moving in a gravitational field, develops an area dependence when it approaches the horizon of a static, spherically symmetric spacetime. Here we extend the above result in two directions; viz., to (a) the stationary axisymmteric spacetimes and (b) time dependent cosmological spacetimes evolving asymptotically to the de Sitter or the Schwarzschild de Sitter spacetimes. While our calculations are exact for the stationary axisymmetric spacetimes, for the cosmological case we present an analytical expression of the entropy when the spacetime is close to the de Sitter or the Schwarzschild de Sitter spacetime. Unlike the static spacetimes, there is no hypersurface orthogonal timelike Killing vector field in these cases. Nevertheless, the results hold and the entropy develops an area dependence in the appropriate limit.
description: v2, 19pp; added discussions and clarifications, improved presentation; results unchanged; to appear in PRD
A Universal Construction for (Co)Relations
Creators: name: Fong, Brendan
name: Zanasi, Fabio
Publisher: name: arXiv
Year: 2017
Subjects: subject: Logic in Computer Science (cs.LO)
subject: Category Theory (math.CT)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics
subject: F.3.2

description: Calculi of string diagrams are increasingly used to present the syntax and algebraic structure of various families of circuits, including signal flow graphs, electrical circuits and quantum processes. In many such approaches, the semantic interpretation for diagrams is given in terms of relations or corelations (generalised equivalence relations) of some kind. In this paper we show how semantic categories of both relations and corelations can be characterised as colimits of simpler categories. This modular perspective is important as it simplifies the task of giving a complete axiomatisation for semantic equivalence of string diagrams. Moreover, our general result unifies various theorems that are independently found in literature, including the cases of linear corelations (relevant for the semantics of electrical circuits), of partial equivalence relations and of linear subspaces (semantics of signal flow graphs and of the phase-free ZX calculus).
description: 15 pages + 4 page appendix, CALCO 2017
Quantum-continuum calculation of the surface states and electrical response of silicon in solution
Creators: name: Campbell, Quinn
name: Dabo, Ismaila
Publisher: name: arXiv
Year: 2017
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: A wide range of electrochemical reactions of practical importance occur at the interface between a semiconductor and an electrolyte. We present an embedded density-functional theory method using the recently released self-consistent continuum solvation (SCCS) approach to study these interfaces. In this model, a quantum description of the surface is incorporated into a continuum representation of the bending of the bands within the electrode. The model is applied to understand the electrical response of silicon electrodes in solution, providing microscopic insights into the low-voltage region, where surface states determine the electrification of the semiconductor electrode.
description: 8 pages, 5 figures
title: The power of crystal optics
Creators: name: Fischer, Reinhard X.
name: Shannon, Robert D.
Publisher: name: Deutsche Geologische Gesellschaft - Geologische Vereinigung e.V. (DGGV)
Year: 2022

description:
It is demonstrated here that refractive-index measurements can be used to determine details of chemical compositions and physical properties of crystals. For example, the H2O content of hydrous minerals can be determined from their mean refractive indices with high accuracy as shown for 157 zeolite-type minerals and compounds (Fischer et al., 2020). This is especially important when only small crystals are available not suitable for thermal analyses or for other reliable methods of measuring the amount of H2O. The physical basis for these predictions is the additivity of electronic polarizabilities of cations and anions. If the chemical composition and the molar volume of a compound are known, the total electronic polarizability can be calculated from the sum of the individual polarizabilities of the elements. Using the Anderson-Eggleton equation, the mean refractive index can be calculated. Deviations between observed and calculated mean refractive indices can be used, e.g., to identify ion conductors showing unusually high discrepancies. We have evaluated more than 3000 datasets of minerals and compounds to determine the electronic polarizabilities of four anions and 76 cations in various coordinations. Based on these parameters, the mean refractive index for more than 2000 minerals and compounds could be calculated with an error <2%. Some groups of compounds are identified showing systematic deviations. The results are compared with the Gladstone-Dale approach after Mandarino (1976).

Fischer, R.X., Burianek, M., Shannon, R.D. (2020) Eur. J. Mineral. 32, 27.

Mandarino, J.A. (1976) Can. Mineral. 14, 498.

Shannon, R.D., Fischer, R.X. (2016) Amer. Mineral. 101, 2288.
A unified thermostat scheme for efficient configurational sampling for classical/quantum canonical ensembles via molecular dynamics
Creators: name: Zhang, Zhijun
name: Liu, Xinzijian
name: Chen, Zifei
name: Zheng, Haifeng
name: Yan, Kangyu
name: Liu, Jian
Publisher: name: arXiv
Year: 2017
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Atomic and Molecular Clusters (physics.atm-clus)
subject: Biological Physics (physics.bio-ph)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: We show a unified second-order scheme for constructing simple, robust and accurate algorithms for typical thermostats for configurational sampling for the canonical ensemble. When Langevin dynamics is used, the scheme leads to the BAOAB algorithm that has been recently investigated. We show that the scheme is also useful for other types of thermostat, such as the Andersen thermostat and Nosé-Hoover chain. Two 1-dimensional models and three typical realistic molecular systems that range from the gas phase, clusters, to the condensed phase are used in numerical examples for demonstration. Accuracy may be increased by an order of magnitude for estimating coordinate-dependent properties in molecular dynamics (when the same time interval is used), irrespective of which type of thermostat is applied. The scheme is especially useful for path integral molecular dynamics, because it consistently improves the efficiency for evaluating all thermodynamic properties for any type of thermostat.
description: Manuscript + Supplementary Material. A unified second-order scheme for constructing simple, robust and accurate algorithms for typical thermostats for configurational sampling for the canonical ensemble. (Accepted by J. Chem. Phys.)
On Backreaction in Newtonian cosmology
Creators: name: Buchert, Thomas
Publisher: name: arXiv
Year: 2017
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We clarify that a result recently stated by Kaiser is contained in a theorem of Buchert and Ehlers that is widely known for its main result: that there is no global kinematical backreaction in Newtonian cosmology. Kaiser cites this paper, re-derives parts of the theorem, but incompletely restates its content. He makes further claims, which cannot be proven beyond the limited context of Newtonian cosmology. We also discuss recent papers of Rácz et al. and Roukema who claim the existence of global backreaction within the Newtonian framework.
description: 4 pages; refers to V1 and V2 of arXiv:1703.08809; matches published version in MNRAS Letters
Searches for pair production of third-generation squarks in sqrt(s) = 13 TeV pp collisions
Creators: name: CMS Collaboration
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Searches are presented for direct production of top or bottom squark pairs in proton-proton collisions at the CERN LHC. Two searches, based on complementary techniques, are performed in all-jet final states that are characterized by a significant imbalance in transverse momentum. An additional search requires the presence of a charged lepton isolated from other activity in the event. The data were collected in 2015 at a centre-of-mass energy of 13 TeV with the CMS detector and correspond to an integrated luminosity of 2.3 inverse femtobarns. No statistically significant excess of events is found beyond the expected contribution from standard model processes. Exclusion limits are set in the context of simplified models of top or bottom squark pair production. Models with top and bottom squark masses up to 830 and 890 GeV, respectively, are probed for light neutralinos. For models with top squark masses of 675 GeV, neutralino masses up to 260 GeV are excluded at 95% confidence level.
description: Replaced with the published version. Added the journal reference and DOI. All the figures and tables can be found at http://cms-results.web.cern.ch/cms-results/public-results/publications/SUS-16-008/index.html
The Effect of GUP to Massive Vector and Scalar Particles Tunneling From a Warped DGP Gravity Black Hole
Creators: name: Övgün, Ali
name: Jusufi, Kimet
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Physics (physics.gen-ph)
subject: FOS: Physical sciences

description: This paper discusses the effects of the mass and the angular momentum of massive vector and scalar particles on the Hawking temperature manifested under the effects of the generalized uncertainty principle (GUP). In particular, we calculate the Hawking temperature of a black hole in a warped DGP gravity model in the framework of the quantum tunneling method. We use the modified Proca and Klein-Gordon equations previously determined from the GUP Lagrangian in the spacetime background of a warped Dvali-Gabadadze-Porrati (DGP) metric, with the help of Hamilton-Jacobi (HJ) and semiclassical (WKB) approximation methods. We find that as a special case of a warped DGP black hole solution, the Hawking temperature of a Schwarzschild-de Sitter (SdS) black hole can be determined. Furthermore, the Hawking temperature is influenced by the mass and the angular momentum of vector and scalar particles and depends on which of those types of particles is being emitted by the black hole. We conclude that the nonthermal nature of the Hawking spectrum leads to Planck-scale nonthermal correlations, shedding light on the information paradox in black hole evaporation.
description: 9 pages, accepted for publication in EPJ Plus
AMP-Inspired Deep Networks for Sparse Linear Inverse Problems
Creators: name: Borgerding, Mark
name: Schniter, Philip
name: Rangan, Sundeep
Publisher: name: arXiv
Year: 2016
Subjects: subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences

description: Deep learning has gained great popularity due to its widespread success on many inference problems. We consider the application of deep learning to the sparse linear inverse problem, where one seeks to recover a sparse signal from a few noisy linear measurements. In this paper, we propose two novel neural-network architectures that decouple prediction errors across layers in the same way that the approximate message passing (AMP) algorithms decouple them across iterations: through Onsager correction. First, we propose a "learned AMP" network that significantly improves upon Gregor and LeCun's "learned ISTA." Second, inspired by the recently proposed "vector AMP" (VAMP) algorithm, we propose a "learned VAMP" network that offers increased robustness to deviations in the measurement matrix from i.i.d. Gaussian. In both cases, we jointly learn the linear transforms and scalar nonlinearities of the network. Interestingly, with i.i.d. signals, the linear transforms and scalar nonlinearities prescribed by the VAMP algorithm coincide with the values learned through back-propagation, leading to an intuitive interpretation of learned VAMP. Finally, we apply our methods to two problems from 5G wireless communications: compressive random access and massive-MIMO channel estimation.
description: to appear in IEEE Transactions in Signal Processing
Diffusion, subdiffusion and localisation of active colloids in random post lattices
Creators: name: Morin, Alexandre
name: Cardozo, David Lopes
name: Chikkadi, Vijayakumar
name: Bartolo, Denis
Publisher: name: arXiv
Year: 2017
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Combining experiments and theory, we address the dynamics of self-propelled particles in crowded environments. We first demonstrate that motile colloids cruising at constant speed through random lattices undergo a smooth transition from diffusive, to subdiffusive, to localized dynamics upon increasing the obstacle density. We then elucidate the nature of these transitions by performing extensive simulations constructed from a detailed analysis of the colloid-obstacle interactions. We evidence that repulsion at a distance and hard-core interactions both contribute to slowing down the long-time diffusion of the colloids. In contrast, the localization transition stems solely from excluded-volume interactions and occurs at the void-percolation threshold. Within this critical scenario, equivalent to that of the random Lorentz gas, genuine asymptotic subdiffusion is found only at the critical density where the motile particles explore a fractal maze.
description: 9 pages, 8 figures
Compressive Sensing-Based Detection with Multimodal Dependent Data
Creators: name: Wimalajeewa, Thakshila
name: Varshney, Pramod K.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Applications (stat.AP)
subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences

description: Detection with high dimensional multimodal data is a challenging problem when there are complex inter- and intra- modal dependencies. While several approaches have been proposed for dependent data fusion (e.g., based on copula theory), their advantages come at a high price in terms of computational complexity. In this paper, we treat the detection problem with compressive sensing (CS) where compression at each sensor is achieved via low dimensional random projections. CS has recently been exploited to solve detection problems under various assumptions on the signals of interest, however, its potential for dependent data fusion has not been explored adequately. We exploit the capability of CS to capture statistical properties of uncompressed data in order to compute decision statistics for detection in the compressed domain. First, a Gaussian approximation is employed to perform likelihood ratio (LR) based detection with compressed data. In this approach, inter-modal dependence is captured via a compressed version of the covariance matrix of the concatenated (temporally and spatially) uncompressed data vector. We show that, under certain conditions, this approach with a small number of compressed measurements per node leads to enhanced performance compared to detection with uncompressed data using widely considered suboptimal approaches. Second, we develop a nonparametric approach where a decision statistic based on the second order statistics of uncompressed data is computed in the compressed domain. The second approach is promising over other related nonparametric approaches and the first approach when multimodal data is highly correlated at the expense of slightly increased computational complexity.
Dynamical pruning of the multiconfiguration time-dependent Hartree method (DP-MCTDH): An efficient approach for multidimensional quantum dynamics
Creators: name: Larsson, Henrik R.
name: Tannor, David J.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We present two strategies for combining dynamical pruning with the multiconfiguration time-dependent Hartree method (DP-MCTDH), where dynamical pruning means on-the-fly selection of relevant basis functions. The first strategy prunes the primitive basis that represents the single-particle functions (SPFs). This is useful for smaller systems that require many primitive basis functions per degree of freedom, as we will illustrate for NO$_2$. Furthermore, this allows for higher-dimensional mode combination and partially lifts the sum-of-product-form requirement onto the structure of the Hamiltonian, as we illustrate for nonadiabatic 24-dimensional pyrazine. The second strategy prunes the set of configurations of SPF at each time step. We show that this strategy yields significant speed-ups with factors between 5 and 50 in computing time, making it competitive with the multilayer MCTDH method.
Assessing the impacts of time to detection distribution assumptions on detection probability estimation
Creators: name: Martin-Schwarze, Adam
name: Niemi, Jarad
name: Dixon, Philip
Publisher: name: arXiv
Year: 2016
Subjects: subject: Populations and Evolution (q-bio.PE)
subject: FOS: Biological sciences

description: Abundance estimates from animal point-count surveys require accurate estimates of detection probabilities. The standard model for estimating detection from removal-sampled point-count surveys assumes that organisms at a survey site are detected at a constant rate; however, this assumption is often not justified. We consider a class of N-mixture models that allows for detection heterogeneity over time through a flexibly defined time-to-detection distribution (TTDD) and allows for fixed and random effects for both abundance and detection. Our model is thus a combination of survival time-to-event analysis with unknown-N, unknown-p abundance estimation. We specifically explore two-parameter families of TTDDs, e.g. gamma, that can additionally include a mixture component to model increased probability of detection in the initial observation period. We find that modeling a TTDD by using a two-parameter family is necessary when data have a chance of arising from a distribution of this nature. In addition, models with a mixture component can outperform non-mixture models even when the truth is non-mixture. Finally, we analyze an Overbird data set from the Chippewa National Forest using mixed effect models for both abundance and detection. We demonstrate that the effects of explanatory variables on abundance and detection are consistent across mixture TTDDs but that flexible TTDDs result in lower estimated probabilities of detection and therefore higher estimates of abundance.
description: Expands previous simulation study and adds simulations across a range of `true' detection values
Optimal wall-to-wall transport by incompressible flows
Creators: name: Tobasco, Ian
name: Doering, Charles R.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Analysis of PDEs (math.AP)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We consider wall-to-wall transport of a passive tracer by divergence-free velocity vector fields $\mathbf{u}$. Given an enstrophy budget $\langle |\nabla \mathbf{u}|^{2} \rangle \le Pe^{2}$ we construct steady two-dimensional flows that transport at rates $Nu(\mathbf{u}) \gtrsim Pe^{2/3}/(\log Pe)^{4/3}$ in the large enstrophy limit. Combined with the known upper bound $Nu(\mathbf{u})\lesssim Pe^{2/3}$ for any such enstrophy-constrained flow, we conclude that maximally transporting flows satisfy $Nu\sim Pe^{2/3}$ up to possible logarithmic corrections. Combined with known transport bounds in the context of Rayleigh-Bénard convection this establishes that while suitable flows approaching the "ultimate" heat transport scaling $Nu\sim Ra^{1/2}$ exist, they are not always realizable as buoyancy-driven flows. The result is obtained by exploiting a connection between the wall-to-wall optimal transport problem and a closely related class of singularly perturbed variational problems arising in the study of energy-driven pattern formation in materials science.
description: Edited to take into account referee comments. To appear in Phys. Rev. Lett
Prospects and Applications Near Ferroelectric Quantum Phase Transitions
Creators: name: Chandra, P.
name: Lonzarich, G. G.
name: Rowley, S. E.
name: Scott, J. F.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The emergence of complex and fascinating states of quantum matter in the neighborhood of zero temperature phase transitions suggests that such quantum phenomena should be studied in a variety of settings. Advanced technologies of the future may be fabricated from materials where the cooperative behavior of charge, spin and current can be manipulated at cryogenic temperatures. The propagating lattice dynamics of displacive ferroelectrics make them appealing for the study of quantum critical phenomena that is characterized by both space- and time-dependent quantities. In this Key Issues article we aim to provide a self-contained overview of ferroelectrics near quantum phase transitions. Unlike most magnetic cases, the ferroelectric quantum critical point can be tuned experimentally to reside at, above or below its upper critical dimension; this feature allows for detailed interplay between experiment and theory using both scaling and self-consistent field models. Empirically, the sensitivity of the ferroelectrics $T_c$s to external to chemical pressure gives practical access to a broad range of temperature behavior over several hundreds of Kelvin. Additional degrees of freedom like charge and spin can be added and characterized systematically. Satellite memories, electrocaloric cooling and low-loss phased-array radar are among possible applications of low-temperature ferroelectrics. We end with open questions for future research that include textured polarization states and unusual forms of superconductivity that remain to be understood theoretically.
description: Invited Key Issues article for Reports on the Progress of Physics; References added
2211 Emotions & clothing consumption/activism
Creators: name: Bosshard, Anna
name: Raba, Sara
name: Abera, Benjamin
Publisher: name: Open Science Framework
Year: 2022
Subjects: subject: Social and Behavioral Sciences
subject: Activism
subject: Emotions and pro-environmental behavior
subject: Fast fashion

description: The aim of this study is to better understand thoughts, emotions and various behaviors related to clothing consumption.
Scrutinizing Teachers’ Awareness of Global Citizenship Education (GCED) in Jordan
Creators: name: Al-Husban, Naima
name: Tawalbeh, Mohammad
Publisher: name: Alberta Journal of Educational Research
Year: 2022

description: This study aimed to determine the Global Citizenship Education (GCED) awareness level of teachers of different subjects in Jordan and to investigate whether their global citizenship awareness levels varied in terms of different demographic variables. The sample comprised 4305 teachers. Data were gathered using an awareness scale and an interview. Findings revealed that teachers showed an unsatisfactory level of awareness of GCED; females were more aware of GCED. Based on the results, it is recommended that teachers’ knowledge should be fostered in teaching GCED concepts, skills, and values, and to transcend the teacher-centered approach as it doesn’t promote the outcomes of creating global citizens. Keywords: Teachers’ Awareness, Global Citizenship Education, Demographic Variables, Teacher Development. Cette étude avait pour but de déterminer le niveau de sensibilisation à l'éducation à la citoyenneté mondiale des enseignants de différentes matières en Jordanie et d'examiner si leur niveau de sensibilisation à la citoyenneté mondiale variait en fonction de différentes variables démographiques. L'échantillon comprenait 4 305 enseignants. Les données ont été recueillies à l'aide d'une échelle de sensibilisation et d'un entretien. Les résultats ont révélé que les enseignants ont montré un niveau insatisfaisant de sensibilisation à la citoyenneté mondiale ; les femmes étaient plus sensibilisées à la citoyenneté mondiale. Sur la base des résultats, il est recommandé de renforcer les connaissances des enseignants dans l'enseignement des concepts, des compétences et des valeurs de la citoyenneté mondiale, et de transcender l'approche centrée sur l'enseignant car elle ne favorise pas la création de citoyens du monde. Mots clés : Sensibilisation des enseignants, éducation à la citoyenneté mondiale, variables démographiques, développement des enseignants.
description: Alberta Journal of Educational Research, Vol. 68 No. 4 (2022): Winter
Fault Tolerance with Bare Ancillae for a [[7,1,3]] Code
Creators: name: Li, Muyuan
name: Gutiérrez, Mauricio
name: David, Stanley E.
name: Hernandez, Alonzo
name: Brown, Kenneth R.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We present a [[7, 1, 3]] quantum error-correcting code that is able to achieve fault-tolerant syndrome measurement using one ancillary qubit per stabilizer for an error model of independent single-qubit Pauli errors. All single-qubit Pauli errors on the ancillary qubits propagate to form exclusively correctable errors on the data qubits. The situation changes for error models with two-qubit Pauli errors. We compare the level-1 logical error rates under two noise models: the standard Pauli symmetric depolarizing error model and an anisotropic error model. The anisotropic model is motivated by control errors on two-qubit gates commonly applied to trapped ion qubits. We find that one ancillary qubit per syndrome measurement is sufficient for fault-tolerance for the anisotropic error, but is not sufficient for the standard depolarizing errors. We then show how to achieve fault tolerance for the standard depolarizing errors by adding flag qubits to check for errors on select ancilary qubits. Our results on this [[7, 1, 3]] code demonstrates how physically motivated noise models may simplify fault-tolerent protocols.
From Nodal Chain Semimetal To Weyl Semimetal in HfC
Creators: name: Yu, Rui
name: Wu, Quansheng
name: Fang, Zhong
name: Weng, Hongming
Publisher: name: arXiv
Year: 2017
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Based on first-principles calculations and effective model analysis, we propose that the WC-type HfC, in the absence of spin-orbit coupling (SOC), can host a three-dimensional nodal chain semimetal state. Distinguished from the previous material IrF4 [T. Bzdusek et al., Nature 538, 75 (2016)], the nodal chain here is protected by mirror reflection symmetries of a simple space group, while in IrF4 the nonsymmorphic space group with a glide plane is a necessity. Moreover, in the presence of SOC, the nodal chain in WC type HfC evolves into Weyl points. In the Brillouin zone, a total of 30 pairs of Weyl points in three types are obtained through the first-principles calculations. Besides, the surface states and the pattern of the surface Fermi arcs connecting these Weyl points are studied, which may be measured by future experiments.
description: https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.119.036401
The Gravitational-Wave Physics
Creators: name: Cai, Rong-Gen
name: Cao, Zhoujian
name: Guo, Zong-Kuan
name: Wang, Shao-Jiang
name: Yang, Tao
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The direct detection of gravitational wave by Laser Interferometer Gravitational-Wave Observatory indicates the coming of the era of gravitational-wave astronomy and gravitational-wave cosmology. It is expected that more and more gravitational-wave events will be detected by currently existing and planned gravitational-wave detectors. The gravitational waves open a new window to explore the Universe and various mysteries will be disclosed through the gravitational-wave detection, combined with other cosmological probes. The gravitational-wave physics is not only related to gravitation theory, but also is closely tied to fundamental physics, cosmology and astrophysics. In this review article, three kinds of sources of gravitational waves and relevant physics will be discussed, namely gravitational waves produced during the inflation and preheating phases of the Universe, the gravitational waves produced during the first-order phase transition as the Universe cools down and the gravitational waves from the three phases: inspiral, merger and ringdown of a compact binary system, respectively. We will also discuss the gravitational waves as a standard siren to explore the evolution of the Universe.
description: v1, 37 pages, 7 figures, invited review for National Science Review; v2, revised version to match the online publication version
Reframing Teacher Engagement: A Framework for Improving Workplace Conditions to Foster Teacher Engagement
Creators: name: Heim, Katrin
name: Marshall, Kurtis
Publisher: name: Alberta Journal of Educational Research
Year: 2022

description: Historically, the factors contributing to teacher engagement have been premised on the idea that engagement is grounded in intrinsic motivation and intrapersonal characteristics. This narrative literature review offers an alternative perspective, whereby teacher engagement is enhanced through creating policies to improve workplace conditions and foster engagement. Within the findings, three essential conditions to foster teacher engagement were identified: a supportive organization, active leadership, and healthy interpersonal relationships. A conceptual framework based on these findings is constructed and proposed as an aid to school leaders in policy development to improve teacher engagement. Keywords: Teacher engagement, conditions, policy, framework, school leaders Historiquement, les facteurs contribuant à l'engagement des enseignants ont été basés sur l'idée que l'engagement est fondé sur la motivation intrinsèque et les caractéristiques intrapersonnelles. Cette analyse documentaire narrative propose une autre perspective, selon laquelle l'engagement des enseignants est renforcé par la création de politiques visant à améliorer les conditions de travail et à favoriser l'engagement. Dans les conclusions, trois conditions essentielles pour favoriser l'engagement des enseignants ont été identifiées : une organisation de soutien, un leadership actif et des relations interpersonnelles saines. On construit un cadre conceptuel basé sur ces résultats et on le propose au leadership scolaire comme appui au développement de politiques visant à améliorer l'engagement des enseignants. Mots clés : Engagement des enseignants, conditions, politique, cadre, leadeurship scolaire
description: Alberta Journal of Educational Research, Vol. 68 No. 4 (2022): Winter
Concursos de acceso a plazas de profesorado de Universidad: ejemplo de estructura de contenidos de la documentación a entregar
Creators: name: Gurrutxaga, M.
Publisher: name: Zenodo
Year: 2023
Subjects: cuerpos docentes universitarios, proyecto docente, profesorado de universidad, investigación, epistemología, concurso de acceso

description: Se muestra un ejemplo de estructura de contenidos de la documentación escrita a entregar en concursos de acceso a plazas de cuerpos docentes universitarios, por si sirve de alguna ayuda a personas que estén afrontando su redacción. Este ejemplo está basado en mi experiencia para acceder a una plaza estable en febrero de 2023, que requería entregar a) Curriculum vitae, b) programa docente sobre la materia del perfil de la plaza, c) proyecto(s) de investigación y d) trabajo original de investigación perteneciente al área de conocimiento de la plaza.
The Power of Affect: Teacher Activism as Resistance to Neoliberalism in Saskatchewan
Creators: name: Keil, Trudy
name: Osmond-Johnson, Pamela
Publisher: name: Alberta Journal of Educational Research
Year: 2022

description: With prevailing global neoliberal ideology, teachers and teacher unions must respond to market-driven governmental policies intended to undermine public education. In Saskatchewan, Canada, teacher activists feel compelled to both counter neoliberal discourses and proactively advocate for equitable, high-quality public education. To explore acts of resistance, semi-structured interviews with four teacher activists were employed to understand how teachers enact advocacy within their union and through grassroots activism. Harding et al.’s (2018) framework of alliances, assemblages, and affects informed data analysis, which included the creation of narrative vignettes characterizing teacher voice. This paper specifically discusses findings which suggest that affect, or how emotions do things, presented teachers with new potentialities for shaping educational policy. Keywords: narrative inquiry, teacher unions, grassroots teacher activism, neoliberalism, poststructuralism, affect Face à l'idéologie néolibérale mondiale dominante, les enseignants et les syndicats d'enseignants doivent répondre aux politiques gouvernementales axées sur le marché et destinées à saper l'éducation publique. En Saskatchewan, au Canada, les enseignants militants se sentent obligés de contrer les discours néolibéraux et de défendre de manière proactive une éducation publique équitable et de qualité. Des entretiens semi-structurés avec quatre enseignants militants ont été utilisés pour explorer les actes de résistance et comprendre comment les enseignants défendent leurs intérêts au sein de leur syndicat et par le biais du militantisme de base. Le cadre d'alliances, d'agencements et d'affects de Harding et al. (2018) a guidé l'analyse des données, qui comprenait la création de vignettes narratives caractérisant la voix des enseignants. Cet article traite spécifiquement des résultats qui suggèrent que l'affect, ou la façon dont les émotions font les choses, a présenté aux enseignants de nouvelles potentialités pour façonner la politique éducative. Mots clés : enquête narrative, syndicats d'enseignants, activisme des enseignants de la base, néolibéralisme, poststructuralisme, affect
description: Alberta Journal of Educational Research, Vol. 68 No. 4 (2022): Winter
Concursos de acceso a plazas de profesorado de Universidad: ejemplo de estructura de contenidos de la documentación a entregar
Creators: name: Gurrutxaga, M.
Publisher: name: Zenodo
Year: 2023
Subjects: proyecto docente, proyecto investigador, profesorado de universidad, trabajo de investigación, epistemología, concurso de acceso

description: Se muestra un ejemplo de estructura de contenidos de la documentación escrita a entregar en concursos de acceso a plazas de cuerpos docentes universitarios, por si sirve de alguna ayuda a personas que estén afrontando su redacción. Este ejemplo está basado en mi experiencia para acceder a una plaza estable en febrero de 2023, que requería entregar a) Curriculum vitae, b) programa docente sobre la materia del perfil de la plaza, c) proyecto(s) de investigación y d) trabajo original de investigación perteneciente al área de conocimiento de la plaza.
title: RNA trapping in 3D Hadean hydrothermal submarine vent models
Creators: name: Helmbrecht, Vanessa
name: Orsi, William
Publisher: name: Deutsche Geologische Gesellschaft - Geologische Vereinigung e.V. (DGGV)
Year: 2022

description:
The question on how life emerged on Earth remains one of the biggest mysteries of mankind. Alkaline hydrothermal vents (AHVs) might have played a key role during the transition from pre-biotic chemistry to an RNA-world during the Hadean. Two major theories regarding the emergence of life on Earth are the hydrothermal vent metabolism-first (AHVs) and the information-first (RNA world) theories. It is unknown, whether these theories are mutually exclusive. This PhD project will use controlled laboratory experiments to investigate plausible scenarios, in which RNA is accumulated within the mineral matrix, that forms in AHV models under simulated Hadean ocean conditions.

AHVs are “chemical gardens” with steep eH-pH and T gradients, that would have provided potential energy for proto-life. They contain reactive mineral surfaces like Fe-sulfide and Fe-hydroxide and have a complex internal network of micropockets and channels, that might have concentrated nucleic acids.

We simulate AHVs in an anaerobic chamber containing a N2-atmosphere. The experiment mimics Hadean conditions without oxygen. The setup contains a glass vial filled with the Fe-rich, salty and mildly acidic (pH ~5.5) „ocean“. A syringe injects the alkaline hydrothermal fluid (pH 9 to 12). Chemistry, flow-rate and temperature of the fluid can be varied. As the alkaline fluid mixes with the acidic iron “ocean”, changes in pH cause iron minerals to come out of their stability fields and precipitate forming chimney structures. Different types of RNA added to the „ocean“ before the injection might accumulate inside the hydrothermal chimney.
Ultrafast optical Faraday effect in transparent solids
Creators: name: Wismer, Michael S.
name: Stockman, Mark I.
name: Yakovlev, Vladislav S.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: Optics (physics.optics)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We predict a strong-field ultrafast optical Faraday effect, where a circularly polarized ultrashort optical pulse induces transient chirality in an achiral transparent dielectric. This effect is attractive for time-resolved measurements because it gives access to the non-instantaneity of the nonlinear medium response, and also because it represents relaxation of time-reversal symmetry by all-optical means. We propose probing the induced transient chirality with a weak linearly polarized ultraviolet pulse that is shorter than the near-infrared pump pulse. The predicted effects are ultrafast: the induced chirality vanishes for probe delays exceeding the duration of the near-infrared pulse. This opens up possibilities for applications in ultrafast circular-polarization modulators and analyzers.