cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Discretisation schemes for level sets of planar Gaussian fields
Creators: name: Beliaev, Dmitry
name: Muirhead, Stephen
Publisher: name: arXiv
Year: 2017
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics

description: Smooth random Gaussian functions play an important role in mathematical physics, a main example being the random plane wave model conjectured by Berry to give a universal description of high-energy eigenfunctions of the Laplacian on generic compact manifolds. Our work is motivated by questions about the geometry of such random functions, in particular relating to the structure of their nodal and level sets. We study four discretisation schemes that extract information about level sets of planar Gaussian fields. Each scheme recovers information up to a different level of precision, and each requires a maximum mesh-size in order to be valid with high probability. The first two schemes are generalisations and enhancements of similar schemes that have appeared in the literature [BG16, MW07]; these give complete topological information about the level sets on either a local or global scale. As an application, we improve the results in [BG16] on Russo-Seymour-Welsh estimates for the nodal set of positively-correlated planar Gaussian fields. The third and fourth schemes are, to the best of our knowledge, completely new. The third scheme is specific to the nodal set of the random plane wave, and provides global topological information about the nodal set up to `visible ambiguities'. The fourth scheme gives a way to approximate the mean number of excursion domains of planar Gaussian fields.
description: 43 pages, 14 figures. Published version
A Hamiltonian Formulation of Causal Variational Principles
Creators: name: Finster, Felix
name: Kleiner, Johannes
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mathematical Physics (math-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Causal variational principles, which are the analytic core of the physical theory of causal fermion systems, are found to have an underlying Hamiltonian structure, giving a formulation of the dynamics in terms of physical fields in space-time. After generalizing causal variational principles to a class of lower semi-continuous Lagrangians on a smooth, possibly non-compact manifold, the corresponding Euler-Lagrange equations are derived. In the first part, it is shown under additional smoothness assumptions that the space of solutions of the Euler-Lagrange equations has the structure of a symplectic Fréchet manifold. The symplectic form is constructed as a surface layer integral which is shown to be invariant under the time evolution. In the second part, the results and methods are extended to the non-smooth setting. The physical fields correspond to variations of the universal measure described infinitesimally by one-jets. Evaluating the Euler-Lagrange equations weakly, we derive linearized field equations for these jets. In the final part, our constructions and results are illustrated in a detailed example on $\mathbb{R}^{1,1} \times S^1$ where a local minimizer is given by a measure supported on a two-dimensional lattice.
description: 32 pages, LaTeX, 1 figure, minor corrections (published version)
Control of spontaneous emission of a single quantum emitter through a time-modulated photonic-band-gap environment
Creators: name: Calajò, Giuseppe
name: Rizzuto, Lucia
name: Passante, Roberto
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We consider the spontaneous emission of a two-level quantum emitter, such as an atom or a quantum dot, in a modulated time-dependent environment with a photonic band gap. An example of such an environment is a dynamical photonic crystal or any other environment with a bandgap whose properties are modulated in time, in the effective mass approximation. After introducing our model of dynamical photonic crystal, we show that it allows new possibilities to control and tailor the physical features of the emitted radiation, specifically its frequency spectrum. In the weak coupling limit and in an adiabatic case, we obtain the emitted spectrum and we show the appearance of two lateral peaks due to the presence of the modulated environment, separated from the central peak by the modulation frequency. We show that the two side peaks are not symmetric in height, and that their height ratio can be exploited to investigate the density of states of the environment. Our results show that a dynamical environment can give further possibilities to modify the spontaneous emission features, such as its spectrum and emission rate, with respect to a static one. Observability of the phenomena we obtain is discussed, as well as relevance for tailoring and engineering radiative processes.
description: 9 pages, 3 figures
IFZ news Frühling/Sommer 2010
Creators: name: (:Unkn) Unknown
name: Justus Liebig University Giessen
Publisher: name: Universitätsbibliothek Gießen
Year: 2010
Subjects: subject: ddc:630

description: The Future of Biodiversity : Die Zukunft der Biodiversität - Gene, Arten, Ökosysteme: 40. Jubiläumstagung der Gesellschaft für Ökologie-*amies Biodiversität und Umwelt in Gebirgsregionen Georgiens-*Einfluss des Klimawandels auf die Auenvegetation -*Ein nachhaltiges Siedlungsprojekt in Westafrika-*Grünland-Biodiversität unter erhöhtem atmosphärischen CO2-*Boden, Landschaft und die Vielfalt der Tiere -*Biodiversitätsforschung auf dem Dach der Welt -*Artbildungsprozesse im Ostafrikanischen Riftsystem -*CEMarin: Biodiversität in kolumbianischen Korallenriffen -*SCOPSCO: Bohren nach Biodiversität im ältesten See Europas -*Landnutzung und Diversität in Gewässern Südecuadors -*Diversität von Actinobakterien in feuchtem Baumaterial -*Akustische Diversität bei Insekten -*Nährstoffe als Regulatoren in der Tierernährung -*Neue Juniorprofessur für Säugetierökologie am IFZ -*Biosphere IFZ Mikrobielle Vielfalt im IFZ-Teich.
Self-averaging fluctuations in the chaoticity of simple fluids
Creators: name: Das, Moupriya
name: Green, Jason R.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Chaotic Dynamics (nlin.CD)
subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: Bulk properties of equilibrium liquids are a manifestation of intermolecular forces. Here, we show how these forces imprint on dynamical fluctuations in the Lyapunov exponents for simple fluids with and without attractive forces. While the bulk of the spectrum is strongly self-averaging, the first Lyapunov exponent self-averages only weakly and at a rate that depends on the length scale of the intermolecular forces; short-range repulsive forces quantitatively dominate longer range attractive forces, which act as a weak perturbation that slows the convergence to the thermodynamic limit. Regardless of intermolecular forces, the fluctuations in the Kolmogorov-Sinai entropy rate diverge, as one expects for an extensive quantity, and the spontaneous fluctuations of these dynamical observables obey fluctuation-dissipation like relationships. Together, these results are a representation of the van der Waals picture of fluids and another lens through which we can view the liquid state.
description: 5 pages, 4 figures
IFZ news Sommer 2011
Creators: name: (:Unkn) Unknown
name: Justus Liebig University Giessen
Publisher: name: Universitätsbibliothek Gießen
Year: 2011
Subjects: subject: ddc:570

description: Reisökosysteme der Zukunft -* Wie viel Wasser verdunstet aus dem Grundwasser? -*Regulation des Carnitinstoffwechsels aufgeklärt -*Persistente Samenbanken eine Brücke in die Vergangenheit? -*Exkursion nach Namibia 4 Jahre Suche nach dem Gladiator -*sciencemovies " Gold schürfen, Gift ernten?" -*Biosphere IFZ Was wächst denn da am IFZ?
Proposta de Educação Permanente em Saúde com foco no cuidado à pessoa suicida
Creators: name: Lima, Graziele Zamineli de
name: Moraes, Magali Aparecida Alves de
Publisher: name: Zenodo
Year: 2023
Subjects: Educação continuada
Prevenção ao suicídio

description: Proposta de Educação Permanente em Saúde com foco no cuidado à pessoa suicida aos profissionais de um pronto-socorro.
IFZ news Winter 2011/2012
Creators: name: (:Unkn) Unknown
name: Justus Liebig University Giessen
Publisher: name: Universitätsbibliothek Gießen
Year: 2012
Subjects: subject: ddc:570

description: Grund:Wasser. -*Biokohle auf dem Prüfstand. -*Neue Strukturdetails für gezielte Medikamentenentwicklung. -*Invasive gebietsfremde Pflanzenarten in China. -*In aller Kürze. -*Rapssorten für eine Welt im Klimawandel. -*Schaltergene in der Wurzel. -*Zweite Auflage von " Liebigs Suppenfest" unter starker Beteiligung des IFZ. -*Biosphere IFZ Die Salzgärten des IFZ.
IFZ news Sommer 2012
Creators: name: (:Unkn) Unknown
name: Justus Liebig University Giessen
Publisher: name: Universitätsbibliothek Gießen
Year: 2012
Subjects: subject: ddc:570

description: Doppelt hält besser: AG Tierökologie wirbt zwei BMBF Projektezur Biodiversitätsforschung ein -*Invertase-Aktivität limitiert den Kornertrag von Mais -*Wie viel Schnee verträgt die Krähenbeere? -*Deutsch-israelisch-palästinensischer Workshop -*In aller Kürze -*Antibiotikaresistente Mikroorganismen in Boden und Wasser -*Neue Seminarräume im IFZ -*Der längste IFZ Tag, die kürzeste IFZ Nacht: Offene Türen und Fest am 21. Juni 2012 -*Ausstellung Landschafft Ressourcen zurück in Gießen -*Biosphere IFZ Nachwuchs im IFZ-Teich.
An asymptotic expansion for the normalizing constant of the Conway-Maxwell-Poisson distribution
Creators: name: Gaunt, Robert E.
name: Iyengar, Satish
name: Daalhuis, Adri B. Olde
name: Simsek, Burcin
Publisher: name: arXiv
Year: 2016
Subjects: subject: Statistics Theory (math.ST)
subject: FOS: Mathematics
subject: 60E05, 62E20, 41A60, 33C20

description: The Conway-Maxwell-Poisson distribution is a two-parameter generalisation of the Poisson distribution that can be used to model data that is under- or over-dispersed relative to the Poisson distribution. The normalizing constant $Z(λ,ν)$ is given by an infinite series that in general has no closed form, although several papers have derived approximations for this sum. In this work, we start by using probabilistic argument to obtain the leading term in the asymptotic expansion of $Z(λ,ν)$ in the limit $λ\rightarrow\infty$ that holds for all $ν>0$. We then use an integral representation to obtain the entire asymptotic series and give explicit formulas for the first eight coefficients. We apply this asymptotic series to obtain approximations for the mean, variance, cumulants, skweness, excess kurtosis and raw moments of CMP random variables. Numerical results confirm that these correction terms yield more accurate estimates than those obtained using just the leading order term.
description: 16 pages, to appear in Annals of the Institute of Statistical Mathematics, 2017+
IFZ news Frühling/Sommer 2009
Creators: name: (:Unkn) Unknown
name: Justus Liebig University Giessen
Publisher: name: Universitätsbibliothek Gießen
Year: 2009
Subjects: subject: ddc:630

description: Trotz Krieg wissenschaftliche Zusammenarbeit im Kampfgegen die Desertifikation -*Stadt - Land - Fluss: die stre IFZüge 2009 -*DFG Forschergruppe FOR 666 geht in die zweite Runde -*Humboldt-Stipendiatin erforscht Rhizosphärenbakterien -*S2-Labor des IFZ seit Januar im Normalbetrieb -*In Kürze -*Workshop zur Datenanalyse mit R -*Aufgelesen: Neuerwerbungen der IFZ-Bibliothek -*Eingelesen: Neue Bücher aus dem IFZ -Biosphere IFZ Nützliche Käfer, lästige Käfer.
Designing infographics in health research with patients and the public: A scoping review protocol
Creators: name: Beecher, Blaze
name: O’Doherty, Alan
name: Goulao, Beatriz
name: Jalali, Amirhossein
name: Salsberg, Jon
name: Dore, Elizabeth
name: HANNIGAN, AILISH
Publisher: name: University of Limerick
Year: 2023
Subjects: classificationCode: 42
subject: Health sciences
subject: FOS: Health sciences

description: Information graphics or infographics combine visual representations of information or data with text. They have been used in health research to disseminate research findings, translate knowledge and address challenges in health communication to lay audiences. There is emerging evidence of the design of infographics with the involvement of patients and the public in health research. Approaches to involvement include public and patient involvement, patient engagement and participatory research approaches. To date, there has been no comprehensive review of the literature on the design of infographics with patients and the public in health research. This paper presents a protocol and methodological framework for a scoping review to identify and map the available evidence for the involvement of patients and the public in infographics design in health research. It has been informed by preliminary searches and discussions and will guide the conduct and reporting of this review.
Binarized Convolutional Landmark Localizers for Human Pose Estimation and Face Alignment with Limited Resources
Creators: name: Bulat, Adrian
name: Tzimiropoulos, Georgios
Publisher: name: arXiv
Year: 2017
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Machine Learning (cs.LG)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences

description: Our goal is to design architectures that retain the groundbreaking performance of CNNs for landmark localization and at the same time are lightweight, compact and suitable for applications with limited computational resources. To this end, we make the following contributions: (a) we are the first to study the effect of neural network binarization on localization tasks, namely human pose estimation and face alignment. We exhaustively evaluate various design choices, identify performance bottlenecks, and more importantly propose multiple orthogonal ways to boost performance. (b) Based on our analysis, we propose a novel hierarchical, parallel and multi-scale residual architecture that yields large performance improvement over the standard bottleneck block while having the same number of parameters, thus bridging the gap between the original network and its binarized counterpart. (c) We perform a large number of ablation studies that shed light on the properties and the performance of the proposed block. (d) We present results for experiments on the most challenging datasets for human pose estimation and face alignment, reporting in many cases state-of-the-art performance. Code can be downloaded from https://www.adrianbulat.com/binary-cnn-landmarks
description: ICCV 2017 Oral
IFZ news Winter 2010
Creators: name: (:Unkn) Unknown
name: Justus Liebig University Giessen
Publisher: name: Universitätsbibliothek Gießen
Year: 2010
Subjects: subject: ddc:630

description: Auf Wallace s Spuren -*Kristallisationsroboter -*Prof. Saqib zu Gastbei Pflanzenernährung -*In aller Kürze -*Neueröffnung derIFZ-Werkstatt -*Eingelesen -*Biosphere IFZ.
A Sommerfeld Toolbox for Colored Dark Sectors
Creators: name: Hedri, Sonia El
name: Kaminska, Anna
name: de Vries, Maikel
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We present analytical formulae for the Sommerfeld corrections to the annihilation of massive colored particles into quarks and gluons through the strong interaction. These corrections are essential to accurately compute the dark matter relic density for coannihilation with colored partners. Our formulae allow to compute the Sommerfeld effect, not only for the lowest term in the angular momentum expansion of the amplitude, but for all orders in the partial wave expansion. In particular, we carefully account for the effects of the spin of the annihilating particle on the symmetry of the two-particle wave function. This work focuses on strongly interacting particles of arbitrary spin in the triplet, sextet and octet color representations. For typical velocities during freeze-out, we find that including Sommerfeld corrections on the next-to-leading order partial wave leads to modifications of up to ten to twenty percent on the total annihilation cross section. Complementary to QCD, we generalize our results to particles charged under an arbitrary unbroken SU(N) gauge group, as encountered in dark glueball models. In connection with this paper a Mathematica notebook is provided to compute the Sommerfeld corrections for colored particles up to arbitrary order in the angular momentum expansion.
description: 41 pages, 5 figures, matches EPJC version
IFZ news Winter 2012/2013
Creators: name: (:Unkn) Unknown
name: Justus Liebig University Giessen
Publisher: name: Universitätsbibliothek Gießen
Year: 2012
Subjects: subject: ddc:570

description: Elektroantennografie: von Insekten lernen. -*Lebensmittel, DART und Office Chromatography. -*Invasive Pflanzenarten und Klimawandel. -*Glucose-6-phosphat Dehydrogenase als Ziel für Medikamente. -*Europäisches Biodiesel kann nachhaltig sein.-*Afrikanisch-deutsche Field School am Malawisee. -*Der am besten untersuchte Bach der Welt. -*Biosphere IFZ: Haie im Tierhaus.
Dynamical reduction of the dimensionality of exchange interactions and the "spin-liquid" phase of $κ$-(BEDT-TTF)$_2X$
Creators: name: Powell, B. J.
name: Kenny, E. P.
name: Merino, J.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We show that the anisotropy of the effective spin model for the dimer Mott insulator phase of $κ$-(BEDT-TTF)$_2X$ salts is dramatically different from that of the underlying tight-binding model. Intra-dimer quantum interference results in a model of coupled spin chains, where frustrated interchain interactions suppress long-range magnetic order. Thus, we argue, the "spin liquid" phase observed in some of these materials is a remnant of the Tomonaga-Luttinger physics of a single chain. This is consistent with previous experiments and resolves some outstanding puzzles. An erratum [Phys. Rev. Lett. 120, 199901 (2018).] is added as an appendix.
description: Accepted by PRL, 6 pages, 5 figures
IFZ news Herbst/Winter 2009
Creators: name: (:Unkn) Unknown
name: Justus Liebig University Giessen
Publisher: name: Universitätsbibliothek Gießen
Year: 2009
Subjects: subject: ddc:630

description: Neues Exzellenzzentrum Meereswissenschaften baut auf Jahrzehnte Kooperation von JLU und Santa Marta/Kolumbien. -*Prof. Dr. Katja Becker in Nationalakademie Leopoldina gewählt. -*Klimawandel und Ökologie. -*Datenmanagement des SFB 299 wird Best-Practice Beispiel. -*In-situ Sanierung schwermetallbelasteter Böden in Georgien.
Hopf potentials for the Schrödinger operator
Creators: name: Orsina, Luigi
name: Ponce, Augusto C.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 35B05, 35B50 (Primary), 31B15, 31B35 (Secondary)

description: We establish the Hopf boundary point lemma for the Schrödinger operator $-Δ+ V$ involving potentials $V$ that merely belong to the space $L^{1}_{loc}(Ω)$. More precisely, we prove that among all supersolutions $u$ of $-Δ+ V$ which vanish on the boundary $\partialΩ$ and are such that $V u \in L^{1}(Ω)$, if there exists one supersolution which satisfies $\partial u/\partial n < 0$ almost everywhere on $\partialΩ$ with respect to the outward unit vector $n$, then such a property holds for every nontrivial supersolution in the same class. We rely on the existence of nontrivial solutions of the nonhomogeneous Dirichlet problem with boundary datum in $L^{\infty}(\partialΩ)$.
description: Arxiv title has been modified to coincide with the paper as published
Angular momentum evolution in Dark Matter haloes: a study of the Bolshoi and Millennium simulations
Creators: name: Contreras, S.
name: Padilla, N.
name: Lagos, C. D. P.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We use three different cosmological dark matter simulations to study how the orientation of the angular momentum vector (AM) in dark matter haloes evolve with time. We find that haloes in this kind of simulations are constantly affected by a spurious change of mass, which translates into an artificial change in the orientation of the AM. After removing the haloes affected by artificial mass change, we found that the change in the orientation of the AM vector is correlated with time. The change in its angle and direction (i.e. the angle subtended by the AM vector in two consecutive timesteps) that affect the AM vector has a dependence on the change of mass that affects a halo, the time elapsed in which the change of mass occurs and the halo mass. We create a Monte-Carlo simulation that reproduces the change of angle and direction of the AM vector. We reproduce the angular separation of the AM vector since a look back time of 8.5 Gyrs to today ( $\rm α$) with an accuracy of approximately 0.05 in $\rm cos(α)$. We are releasing this Monte-Carlo simulation together with this publication. We also create a Monte Carlo simulation that reproduces the change of the AM modulus. We find that haloes in denser environments display the most dramatic evolution in their AM direction, as well as haloes with a lower specific AM modulus. These relations could be used to improve the way we follow the AM vector in low-resolution simulations.
description: Accepted by MNRAS
Doubly magic nuclei from Lattice QCD forces at $M_{PS}=$469 MeV/c$^2$
Creators: name: McIlroy, C.
name: Barbieri, C.
name: Inoue, T.
name: Doi, T.
name: Hatsuda, T.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We perform ab initio self-consistent Green's function calculations of the closed shell nuclei $^{\rm 4}$He, $^{\rm 16}$O and $^{\rm 40}$Ca, based on two-nucleon potentials derived from Lattice QCD simulations, in the flavor SU(3) limit and at the pseudo-scalar meson mass of 469~MeV/c$^{\rm 2}$. The nucleon-nucleon interaction is obtained using the HAL QCD method and its short-distance repulsion is treated by means of ladder resummations outside the model space. Our results show that this approach diagonalises ultraviolet degrees of freedom correctly. Therefore, ground state energies can be obtained from infrared extrapolations even for the relatively hard potentials of HAL QCD. Comparing to previous Brueckner Hartree-Fock calculations, the total binding energies are sensibly improved by the full account of many-body correlations. The results suggest an interesting possible behaviour in which nuclei are unbound at very large pion masses and islands of stability appear at first around the traditional doubly-magic numbers when the pion mass is lowered toward its physical value. The calculated one-nucleon spectral distributions are qualitatively close to those of real nuclei even for the pseudo-scalar meson mass considered here.
description: 7 pages, 4 figures, RIKEN-QHP-286, RIKEN-iTHEMS-Report-17
Ubiquitous formation of bulk Dirac cones and topological surface states from a single orbital manifold in transition-metal dichalcogenides
Creators: name: Bahramy, M. S.
name: Clark, O. J.
name: Yang, B. -J.
name: Feng, J.
name: Bawden, L.
name: Riley, J. M.
name: Marković, I.
name: Mazzola, F.
name: Sunko, V.
name: Biswas, D.
name: Cooil, S. P.
name: Jorge, M.
name: Wells, J. W.
name: Leandersson, M.
name: Balasubramanian, T.
name: Fujii, J.
name: Vobornik, I.
name: Rault, J. E.
name: Kim, T. K.
name: Hoesch, M.
name: Okawa, K.
name: Asakawa, M.
name: Sasagawa, T.
name: Eknapakul, T.
name: Meevasana, W.
name: King, P. D. C.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Transition-metal dichalcogenides (TMDs) are renowned for their rich and varied properties. They range from metals and superconductors to strongly spin-orbit-coupled semiconductors and charge-density-wave systems, with their single-layer variants one of the most prominent current examples of two-dimensional materials beyond graphene. Their varied ground states largely depend on the transition metal d-electron-derived electronic states, on which the vast majority of attention has been concentrated to date. Here, we focus on the chalcogen-derived states. From density-functional theory calculations together with spin- and angle- resolved photoemission, we find that these generically host type-II three-dimensional bulk Dirac fermions as well as ladders of topological surface states and surface resonances. We demonstrate how these naturally arise within a single p-orbital manifold as a general consequence of a trigonal crystal field, and as such can be expected across a large number of compounds. Already, we demonstrate their existence in six separate TMDs, opening routes to tune, and ultimately exploit, their topological physics.
description: 10 pages, 4 figures
Lattice realization of a bosonic integer quantum Hall state - trivial insulator transition and relation to the self-dual line in the easy-plane NCCP1 model
Creators: name: Geraedts, Scott D.
name: Motrunich, Olexei I.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We provide an explicit lattice model of bosons with two separately conserved boson species [$U(1)\times U(1)$ global symmetry] realizing a direct transition between an integer quantum Hall effect of bosons and a trivial phase, where any intermediate phase is avoided by an additional symmetry interchanging the two species. If the latter symmetry is absent, we find intermediate superfluid phases where one or the other boson species condenses. We know the precise location of the transition since at this point our model has an exact non-local anti-unitary particle-hole-like symmetry that resembles particle-hole symmetry in the lowest Landau level of electrons. We exactly map the direct transition to our earlier study of the self-dual line of the easy-plane NCCP1 model, in the mathematically equivalent reformulation in terms of two (new) particles with $π$-statistics and identical energetics. While the transition in our model is first-order, we hope that our mappings and recent renewed interest in such self-dual models will stimulate more searches for models with a continuous transition.
description: 10 pages + appendix, 3 figures
Nonadiabatic dynamics of the excited states for the Lipkin-Meshkov-Glick model
Creators: name: Kopylov, Wassilij
name: Schaller, Gernot
name: Brandes, Tobias
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We theoretically investigate the impact of the excited state quantum phase transition on the adiabatic dynamics for the Lipkin-Meshkov-Glick model. Using a time dependent protocol, we continuously change a model parameter and then discuss the scaling properties of the system especially close to the excited state quantum phase transition where we find that these depend on the energy eigenstate. On top, we show that the mean-field dynamics with the time dependent protocol gives the correct scaling and expectation values in the thermodynamic limit even for the excited states.
Symmetry-protected topological states for interacting fermions in alkaline-earth-like atoms
Creators: name: Zhou, Xiaofan
name: Pan, Jian-Song
name: Liu, Zheng-Xin
name: Zhang, Wei
name: Yi, Wei
name: Chen, Gang
name: Jia, Suotang
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Atomic Physics (physics.atom-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We discuss the quantum simulation of symmetry-protected topological (SPT) states for interacting fermions in quasi-one-dimensional gases of alkaline-earth-like atoms such as $^{173}$Yb. Taking advantage of the separation of orbital and nuclear-spin degrees of freedom in these atoms, we consider Raman-assisted spin-orbit couplings in the clock states, which, together with the spin-exchange interactions in the clock-state manifolds, give rise to SPT states for interacting fermions. We numerically investigate the phase diagram of the system, and study the phase transitions between the SPT phase and the symmetry-breaking phases. The interaction-driven topological phase transition can be probed by measuring local density distribution of the topological edge modes.
description: 6 pages, 4 figures
The Mont Blanc neutrinos from SN 1987A: Could they have been monochromatic (8 MeV) tachyons with $m^2=-0.38$ keV$^2$?
Creators: name: Ehrlich, Robert
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Here we consider faster-than-light neutrinos having $m_ν^2=-0.38$ $keV^2$ as the explanation of the Mont Blanc burst. It is shown that the Mont Blanc burst is consistent with the distinctive signature of that explanation i.e., an 8 MeV antineutrino line from SN 1987A. It is further shown that a model of core collapse supernovae involving dark matter particles of mass 8 MeV would in fact yield an 8 MeV antineutrino line. Moreover, that dark matter model predicts 8 MeV $ν,\barν$ and $e^+e^-$ pairs from the galactic center, a place where one would expect large amounts of dark matter to collect. The resulting $e^+$ would create $γ-$rays from the galactic center, and a fit to MeV $γ-$ray data yields the model's dark matter mass, as well as the calculated source temperature and angular size. More direct support comes from the spectrum of $N\sim1000$ events recorded by the Kamiokande-II detector on the day of SN 1987A, which appear to show an 8 MeV line atop the detector background. This $\barν$ line, if genuine, has been well-hidden for 30 years because it occurs very close to the peak of the background. This fact might ordinarily justify extreme skepticism. In the present case, however, a more positive view is called for based on (a) the very high statistical significance of the result $(30 σ),$ (b) the use of a detector background independent of the SN 1987A data using a later K-II data set, and (c) the observation of an excess above the background spectrum whose central energy and width both agree with that of an 8 MeV $\barν$ line broadened by $25\%$ resolution. Lastly, it is noted that the tachyonic interpretation of the Mont Blanc burst fits the author's earlier unconventional $3+3$ model of the neutrino mass states.
Lorentz Gauge Theory of Gravity in Electron Positron Colliders
Creators: name: Borzou, Ahmad
name: Cleaver, Gerald
name: Mirza, Behrouz
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: Lorentz gauge theory (LGT) is a feasible candidate for theory of quantum gravity in which routine field theory calculations can be carried out perturbatively without encountering too many divergences. In LGT spin of matter also gravitates. The spin-generated gravity is expected to be extremely stronger than that generated by mass and could be explored in current colliders. In this article the observable signals of the theory in an electron-positron collider is investigated. We specifically study pair annihilation into two gravitons, and LGT corrections to processes like $e^-+e^+\rightarrow μ^-+μ^+$ and $e^-+e^+\rightarrow e^-+e^+$.
description: 12 pages, 3 figures, accepted for publication in CQG
Solvable models for neutral modes in fractional quantum Hall edges
Creators: name: Heinrich, Chris
name: Levin, Michael
Publisher: name: arXiv
Year: 2017
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We describe solvable models that capture how impurity scattering in certain fractional quantum Hall edges can give rise to a neutral mode --- i.e. an edge mode that does not carry electric charge. These models consist of two counter-propagating chiral Luttinger liquids together with a collection of discrete impurity scatterers. Our main result is an exact solution of these models in the limit of infinitely strong impurity scattering. From this solution, we explicitly derive the existence of a neutral mode and we determine all of its microscopic properties including its velocity. We also study the stability of the neutral mode and show that it survives at finite but sufficiently strong scattering. Our results are applicable to a family of Abelian fractional quantum Hall states of which the $ν= 2/3$ state is the most prominent example.
description: Published version
Overhanging of membranes and filaments adhering to periodic graph substrates
Creators: name: Miura, Tatsuya
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mathematical Physics (math-ph)
subject: Classical Analysis and ODEs (math.CA)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: This paper mathematically studies membranes and filaments adhering to periodic patterned substrates in a one-dimensional model. The problem is formulated by the minimizing problem of an elastic energy with a contact potential on graph substrates. Global minimizers (ground states) are mainly considered in view of their graph representations. Our main results exhibit sufficient conditions for the graph representation and examples of situations where any global minimizer must overhang.
description: 20 pages, 15 figures
Renormalization group in super-renormalizable quantum gravity
Creators: name: Modesto, Leonardo
name: Rachwal, Leslaw
name: Shapiro, Ilya L.
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: One of the main advantages of super-renormalizable higher derivative quantum gravity models is the possibility to derive exact beta functions, by making perturbative one-loop calculations. We perform such a calculation for the Newton constant by using the Barvinsky-Vilkovisky trace technology. The result is well-defined in a large class of models of gravity in the sense that the renormalization group beta functions do not depend on the gauge-fixing condition. Finally, we discuss the possibility to apply the results to a large class of nonlocal gravitational theories which are free of massive ghost-like states at the tree-level.
description: 21 pages, journal version, improved and with two new appendices
IFZ news Sommer 2018
Creators: name: (:Unkn) Unknown
name: Justus Liebig University Giessen
Publisher: name: Universitätsbibliothek Gießen
Year: 2018
Subjects: subject: ddc:570

description: Züchtung stresstoleranter Sorghumhirsen für eine bienenfreundliche Biogaserzeugung - iFZ Masters 2017 - Wälder, Wasser und Leben am Nil - Summer School Mikrobielle Bioinformatik in Kolumbien - Antibiotika-Leitstrukturen aus Nacktschnecken - Belastbarkeit der Eisenten-Population - streiFZüge 2018 - Biosphere iFZ: Nützlinge in den Wintergärten
Effect of cooling roofs on gust wind speed over an urban agglomeration in Southern China
Creators: name: Wang, Xueyuan
Publisher: name: figshare
Year: 2023
Subjects: classificationCode: 370108
subject: Meteorology

description: The site observation and simulation data (CTL case) include 2 files: "Urban_OBS_and_CTL_simulated_data.nc”, and Rural_OBS_and_CTL_simulated_data.nc". Each file includes 2208 hours of 3 variables, including the wind speed at 10m (WS10m), temperature at 2m (T2m), and relative humidity at 2m (RH2m).The WR and GR case simulated differences of the wind speed (WS), gust wind speed (GWS), friction velocity, atmospheric stability, and wind shear averaged in the daytime, nighttime, and daily mean in the inner model domain (110*130) are in the files "WR_GR_difference_WS.nc", "WR_GR_difference_GWS.nc", "WR_GR_difference_friction_velocity.nc", "WR_GR_difference_stability.nc", and "WR_GR_difference_wind shear.nc".The WR and GR simulated probability distribution differences of the gust wind speed in the urban areas in the daytime, nighttime, and whole time are in the file "WR_and_GR_probability_differences_GWS.nc".The file "WR_GR_diurnal_LIR_HIR_COI_mean_data" includes the WR and GR simulated hourly-averaged differences of wind speed (WS), gust wind speed (GWS), friction velocity, atmospheric stability, and wind shear in city-wide urban areas.The file "WR_GR_contribution_urban" includes the WR and GR simulated hourly-averaged differences of the gust wind speed (GWS), and contributions of wind speed (WS), turbulence (item 2 in Equation (S1)), and deep convection (item 3 in Equation (S1)) to the gust wind speed in city-wide urban areas.
Hardware for Machine Learning: Challenges and Opportunities
Creators: name: Sze, Vivienne
name: Chen, Yu-Hsin
name: Emer, Joel
name: Suleiman, Amr
name: Zhang, Zhengdong
Publisher: name: arXiv
Year: 2016
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Machine learning plays a critical role in extracting meaningful information out of the zetabytes of sensor data collected every day. For some applications, the goal is to analyze and understand the data to identify trends (e.g., surveillance, portable/wearable electronics); in other applications, the goal is to take immediate action based the data (e.g., robotics/drones, self-driving cars, smart Internet of Things). For many of these applications, local embedded processing near the sensor is preferred over the cloud due to privacy or latency concerns, or limitations in the communication bandwidth. However, at the sensor there are often stringent constraints on energy consumption and cost in addition to throughput and accuracy requirements. Furthermore, flexibility is often required such that the processing can be adapted for different applications or environments (e.g., update the weights and model in the classifier). In many applications, machine learning often involves transforming the input data into a higher dimensional space, which, along with programmable weights, increases data movement and consequently energy consumption. In this paper, we will discuss how these challenges can be addressed at various levels of hardware design ranging from architecture, hardware-friendly algorithms, mixed-signal circuits, and advanced technologies (including memories and sensors).
description: Published as an invited conference paper at CICC 2017
Probabilistic $N$-$k$ Failure-Identification for Power Systems
Creators: name: Sundar, Kaarthik
name: Coffrin, Carleton
name: Nagarajan, Harsha
name: Bent, Russell
Publisher: name: arXiv
Year: 2017
Subjects: subject: Systems and Control (eess.SY)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: This paper considers a probabilistic generalization of the $N$-$k$ failure-identification problem in power transmission networks, where the probability of failure of each component in the network is known a priori and the goal of the problem is to find a set of $k$ components that maximizes disruption to the system loads weighted by the probability of simultaneous failure of the $k$ components. The resulting problem is formulated as a bilevel mixed-integer nonlinear program. Convex relaxations, linear approximations, and heuristics are developed to obtain feasible solutions that are close to the optimum. A general cutting-plane algorithm is proposed to solve the convex relaxation and linear approximations of the $N$-$k$ problem. Extensive numerical results corroborate the effectiveness of the proposed algorithms on small-, medium-, and large-scale test instances, the test instances include the IEEE 14-bus system, the IEEE single-area and three-area RTS96 systems, the IEEE 118-bus system, the WECC 240-bus test system, the 1354-bus PEGASE system, and the 2383-bus Polish winter-peak test system.
description: 17 pages, Networks, 2018
IFZ news Sommer 2019
Creators: name: (:Unkn) Unknown
name: Justus Liebig University Giessen
Publisher: name: Universitätsbibliothek Gießen
Year: 2019
Subjects: subject: ddc:570

description: iFZ ist Typuslokalität für neue Schwammart - iFZ Masters 2018 - Umweltveränderungen in Biodiversitäts-Hotspot-Systemen - Eine Flagelle für alle Bedingungen - iFZ Aktionstag für Groß und Klein - Biosphere iFZ: Insekten-Aktionstag auch Anstoß für einen bunteren Campus
title: Willingness to Pay for environmental attributes
Creators: name: Ribeiro, Jose Eduardo Carvalho
Publisher: name: University of Kent
Year: 2023

description: This thesis investigates the consumers' motivations to buy, and estimation of the willingness to pay for, organic food and the environmental attributes associated with it. These attributes include environment friendliness, animal welfare, low chemical usage, health, and quality, all shown to be significant parameters of social welfare. The thesis estimates results from revealed, stated and combined data, addressing the issues associated with single estimations, above all hypothetical bias, collinearity and endogeneity of attributes, and data scale differences. The true reasons why consumers appreciate environmental attributes, and their driving behaviour, are imperative from a marketing, industry and policy perspectives.
Divergence-free $H$(div)-FEM for time-dependent incompressible flows with applications to high Reynolds number vortex dynamics
Creators: name: Schroeder, Philipp W.
name: Lube, Gert
Publisher: name: arXiv
Year: 2017
Subjects: subject: Numerical Analysis (math.NA)
subject: Computational Physics (physics.comp-ph)
subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: 35Q30, 65M15, 65M60, 76D17, 76M10

description: In this article, we consider exactly divergence-free $H$(div)-conforming finite element methods for time-dependent incompressible viscous flow problems. This is an extension of previous research concerning divergence-free $H^1$-conforming methods. For the linearised Oseen case, the first semi-discrete numerical analysis for time-dependent flows is presented here whereby special emphasis is put on pressure- and Reynolds-semi-robustness. For convection-dominated problems, the proposed method relies on a velocity jump upwind stabilisation which is not gradient-based. Complementing the theoretical results, $H$(div)-FEM are applied to the simulation of full nonlinear Navier-Stokes problems. Focussing on dynamic high Reynolds number examples with vortical structures, the proposed method proves to be capable of reliably handling the planar lattice flow problem, Kelvin-Helmholtz instabilities and freely decaying two-dimensional turbulence.
description: 29 pages, 9 figures, 2 tables
IFZ news Winter 2019/20
Creators: name: (:Unkn) Unknown
name: Justus Liebig University Giessen
Publisher: name: Universitätsbibliothek Gießen
Year: 2019
Subjects: subject: ddc:570

description: 50 Jahre Pflanzenökologie in Gießen - Phylogeographie und Köcherfliegenseide - Biofunktionalität von Futtermitteln - Phosphataneignung: Multitalent Weiße Lupine - Interdisziplinär-Interkulturelle Studienreise nach Kosovo und Albanien - Biosphere iFZ: Diverser Magerrasen statt Monokultur
IFZ news Winter 2018/19
Creators: name: (:Unkn) Unknown
name: Justus Liebig University Giessen
Publisher: name: Universitätsbibliothek Gießen
Year: 2018
Subjects: subject: ddc:570

description: 20 Jahre FACE Linden - Boden-Pflanze-Wechselwirkungen im Global Change - Insektenmehl ist gut für Stoffwechsel fettleibiger Ratten - Mit der Genschere gegen Schadinsekten - SETAC GLB Nachwuchs-Förderpreis für Leonard Böhm - Internationale Konferenz zur Artenbildung in Langzeit-Seen - Hochpathogene Vogeltrichomonose weit unter Wildvögeln verbreitet
Driven dissipative dynamics and topology of quantum impurity systems
Creators: name: Hur, Karyn Le
name: Henriet, Loïc
name: Herviou, Loïc
name: Plekhanov, Kirill
name: Petrescu, Alexandru
name: Goren, Tal
name: Schiro, Marco
name: Mora, Christophe
name: Orth, Peter P.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: In this review, we provide an introduction and overview to some more recent advances in real-time dynamics of quantum impurity models and their realizations in quantum devices. We focus on the Ohmic spin-boson and related models, which describes a single spin-1/2 coupled to an infinite collection of harmonic oscillators. The topics are largely drawn from our efforts over the past years, but we also present a few novel results. In the first part of this review, we begin with a pedagogical introduction to the real-time dynamics of a dissipative spin at both high and low temperatures. We then focus on the driven dynamics in the quantum regime beyond the limit of weak spin-bath coupling. In these situations, the non-perturbative stochastic Schroedinger equation method is ideally suited to numerically obtain the spin dynamics as it can incorporate bias fields $h_z(t)$ of arbitrary time-dependence in the Hamiltonian. We present different recent applications of this method: (i) how topological properties of the spin such as the Berry curvature and the Chern number can be measured dynamically, and how dissipation affects the topology and the measurement protocol, (ii) how quantum spin chains can experience synchronization dynamics via coupling to a common bath. In the second part of this review, we discuss quantum engineering of spin-boson and related models in circuit quantum electrodynamics (cQED), quantum electrical circuits and cold-atoms architectures. In different realizations, the Ohmic environment can be represented by a long (microwave) transmission line, a Luttinger liquid, a one-dimensional Bose-Einstein condensate, a chain of superconducting Josephson junctions. We show that the quantum impurity can be used as a quantum sensor to detect properties of a bath at minimal coupling, and how dissipative spin dynamics can lead to new insight in the Mott-Superfluid transition.
description: 39 pages, invited review, Comptes Rendus Acad\'emie des Sciences, Special Issue on Quantum Simulators, Version as published
Charge and flux insensitive tunable superconducting qubit
Creators: name: Sete, Eyob A.
name: Reagor, Matthew
name: Didier, Nicolas
name: Rigetti, Chad T.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Superconducting qubits with in-situ tunable properties are important for constructing a quantum computer. Qubit tunability, however, often comes at the expense of increased noise sensitivity. Here, we propose a flux-tunable superconducting qubit that minimizes the dephasing due to magnetic flux noise by engineering controllable flux "sweet spots" at frequencies of interest. This is realized by using a SQUID with asymmetric Josephson junctions shunted by a superinductor formed from an array of junctions. Taking into account correlated global and local noises, it is possible to improve dephasing time by several orders of magnitude. The proposed qubit can be used to realize fast, high-fidelity two-qubit gates in large-scale quantum processors, a key ingredient for implementing fault-tolerant quantum computers.
description: 8 pages and 4 figures