cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
AdS$_3$ to dS$_3$ transition in the near horizon of asymptotically de Sitter solutions
Creators: name: Sadeghian, S.
name: Vahidinia, M. H.
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider two solutions of Einstein-$Λ$ theory which admit the extremal vanishing horizon (EVH) limit, odd-dimensional multi-spinning Kerr black hole (in the presence of cosmological constant) and cosmological soliton. We show that the near horizon EVH geometry of Kerr has a 3d maximally symmetric subspace whose curvature depends on rotational parameters and the cosmological constant. In the Kerr-dS case, this subspace interpolates between AdS$_3$, 3d flat and dS$_3$ by varying rotational parameters, while, the near horizon of the EVH cosmological soliton always has a dS$_3$. The feature of the EVH cosmological soliton is that it is regular everywhere on the horizon. In the near EVH case, these 3d parts turn into the corresponding locally maximally symmetric spacetimes with a horizon: Kerr-dS$_3$, flat space cosmology or BTZ black hole. We show that their thermodynamics match with the thermodynamics of the original near EVH black holes. We also briefly discuss the holographic 2d CFT dual to the near horizon of EVH solutions.
description: 27 pages, 2 figures
Approximately certifying the restricted isometry property is hard
Creators: name: Weed, Jonathan
Publisher: name: arXiv
Year: 2017
Subjects: subject: Computational Complexity (cs.CC)
subject: FOS: Computer and information sciences

description: A matrix is said to possess the Restricted Isometry Property (RIP) if it acts as an approximate isometry when restricted to sparse vectors. Previous work has shown it to be NP-hard to determine whether a matrix possess this property, but only in a narrow range of parameters. In this work, we show that it is NP-hard to make this determination for any accuracy parameter, even when we restrict ourselves to instances which are either RIP or far from being RIP. This result implies that it is NP-hard to approximate the range of parameters for which a matrix possesses the Restricted Isometry Property with accuracy better than some constant. Ours is the first work to prove such a claim without any additional assumptions.
Formally Verified Compositional Algorithms for Factored Transition Systems
Creators: name: Abdulaziz, Mohammad
Publisher: name: The Australian National University
Year: 2018
Subjects: Transition Systems
Theorem Proving
Succinct Graphs
Diameter
Reachability
AI Planning
Model checking

description: Artificial Intelligence (AI) planning and model checking are two disciplines that found wide practical applications. It is often the case that a problem in those two fields concerns a transition system whose behaviour can be encoded in a digraph that models the system's state space. However, due to the very large size of state spaces of realistic systems, they are compactly represented as propositionally factored transition systems. These representations have the advantage of being exponentially smaller than the state space of the represented system. Many problems in AI~planning and model checking involve questions about state spaces, which correspond to graph theoretic questions on digraphs modelling the state spaces. However, existing techniques to answer those graph theoretic questions effectively require, in the worst case, constructing the digraph that models the state space, by expanding the propositionally factored representation of the system. This is not practical, if not impossible, in many cases because of the state space size compared to the factored representation. One common approach that is used to avoid constructing the state space is the compositional approach, where only smaller abstractions of the system at hand are processed and the given problem (e.g. reachability) is solved for them. Then, a solution for the problem on the concrete system is derived from the solutions of the problem on the abstract systems. The motivation of this approach is that, in the worst case, one need only construct the state spaces of the abstractions which can be exponentially smaller than the state space of the concrete system. We study the application of the compositional approach to two fundamental problems on transition systems: upper-bounding the topological properties (e.g. the largest distance between any two states, i.e. the diameter) of the state spa ce, and computing reachability between states. We provide new compositional algorithms to solve both problems by exploiting different structures of the given system. In addition to the use of an existing abstraction (usually referred to as projection) based on removing state space variables, we develop two new abstractions for use within our compositional algorithms. One of the new abstractions is also based on state variables, while the other is based on assignments to state variables. We theoretically and experimentally show that our new compositional algorithms improve the state-of-the-art in solving both problems, upper-bounding state space topological parameters and reachability. We designed the algorithms as well as formally verified them with the aid of an interactive theorem prover. This is the first application that we are aware of, for such a theorem prover based methodology to the design of new algorithms in either AI~planning or model checking.
'Fabricated Security Space': The Manus Regional Processing Centre and gendered discourse between Australia and Papua New Guinea
Creators: name: Rooney, Nayahamui Michelle
Publisher: name: Canberra, ACT: Dept. of Pacific Affairs, Coral Bell School of Asia Pacific Affairs, The Australian National University
Year: 2023
Subjects: Security
Manus Island
PNG

description: Global processes such as mass human migration because of conflict or natural disasters, geopolitical rivalries, climate-induced insecurity and other forces have heightened policy focus on security. This has included securitisation processes, wherein issues that may have previously been regarded as social or humanitarian challenges are increasingly viewed as security threats. This paper draws on feminist security studies and the analytical frame of a ‘fabricated security space’ to examine the gendered dimensions of the security and securitisation discourses in the bilateral relationship between Australia and Papua New Guinea (PNG) between 2012 and 2019. Specifically, I focus on Australia’s offshore detention of asylum seekers in the Manus Regional Processing Centre (RPC) during this period as one aspect of this bilateral relationship. The Australian policy and resultant highly secured detention centre complex were superimposed onto PNG’s own diverse and complex social fabric of security characterised by gendered social relationships. The Manus RPC complex, and the actors who arrived with it, set in motion a chain reaction that increasingly revealed the porous nature of this fabricated security space, leading to the undermining of bilateral efforts to address insecurity in the sense of high levels of crime, ethnic violence and gender-based violence in PNG. A key lesson from this period is the need to better appreciate relationality and mutuality in security discourse. Practices, events and discourses in and about each country are simultaneously and relationally shaped by factors domestic, bilateral and beyond, and each country’s contexts. While each country may deal individually with security as a national issue, this case study highlights how practices, policies, events and discourses can flow beyond national borders to shape the bilateral relationship between two countries and the security discourses within each country. This materialises into a range of outcomes that in turn feed back to shape the discourse.
Ab initio electromagnetic observables with the in-medium similarity renormalization group
Creators: name: Parzuchowski, N. M.
name: Stroberg, S. R.
name: Navrátil, P.
name: Hergert, H.
name: Bogner, S. K.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We present the formalism for consistently transforming transition operators within the in-medium similarity renormalization group framework. We implement the operator transformation in both the equations-of-motion and valence-space variants, and present first results for electromagnetic transitions and moments in medium-mass nuclei using consistently-evolved operators, including the induced two-body parts. These results are compared to experimental values, and--where possible--the results of no-core shell model calculations using the same input chiral interaction. We find good agreement between the equations-of-motion and valence space approaches. Magnetic dipole observables are generally in reasonable agreement with experiment, while the more collective electric quadrupole and octupole observables are significantly underpredicted, often by over an order of magnitude, indicating missing physics at the present level of truncation.
description: 19 pages, 13 figures, 3 tables
A deterministic model for forecasting long-term solar activity
Creators: name: Petrakou, Eleni
Publisher: name: arXiv
Year: 2017
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: A phenomenological model is presented for the quantitative description of individual solar cycles' features, such as onset, intensity, evolution, in terms of the number of M and X-class solar flares. The main elements of the model are the relative ecliptic motion of the planets Jupiter and Saturn, and its synergy with a quasi-periodic component of solar activity. Using as input the temporal distribution of flares during cycle 21, the general evolution of cycles 22-24 is reproduced in notable agreement with the observations, including the resurgence of activity in the last months of 2017, and further predictions are provided for cycle 25. This deterministic description could contribute to elucidating the responsible physical mechanisms and forecasting space weather.
description: 15 pages, 6 figures. Update [v3]: Concise version for publication; updated fitting of data and timing scheme (small quantitative changes in results). Update [v2]: Inclusion of X-class flares (no incurred change in results); simplification of the timing scheme (slight change in predictions, simplified systematics); revisited systematic uncertainties; rephrasing for clarity. 2017 events added
2020-TeachingModule-GeometricBehaviorOfLinearSysteModeling
Creators: name: Malagon, Audrey
Publisher: name: QUBES Educational Resources
Year: 2023

description: This module concentrates on the geometric properties of a system of 2 linear, homogeneous first order differential equations in 2 variables as dictated by the corresponding eigenvalues. Students should be familiar with using eigenvalues.
Improved energy methods for nonlocal diffusion problems
Creators: name: Cañizo, J. A.
name: Molino, A.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: We prove an energy inequality for nonlocal diffusion operators of the following type, and some of its generalisations: $Lu (x) := \int_{\mathbb{R}^N} K(x,y) (u(y) - u(x)) dy$, where $L$ acts on a real function $u$ defined on $\mathbb{R}^N$, and we assume that $K(x,y)$ is uniformly strictly positive in a neighbourhood of $x=y$. The inequality is a nonlocal analogue of the Nash inequality, and plays a similar role in the study of the asymptotic decay of solutions to the nonlocal diffusion equation $\partial_t u = L u$ as the Nash inequality does for the heat equation. The inequality allows us to give a precise decay rate of the $L^p$ norms of $u$ and its derivatives. As compared to existing decay results in the literature, our proof is perhaps simpler and gives new results in some cases (particularly, and surprisingly, in dimensions $N = 1, 2$).
Problems on Matchings and Independent Sets of a Graph
Creators: name: Bhattacharya, Amitava
name: Mondal, Anupam
name: Murthy, T. Srinivasa
Publisher: name: arXiv
Year: 2017
Subjects: subject: Combinatorics (math.CO)
subject: Discrete Mathematics (cs.DM)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences
subject: 05C69 (Primary), 05C70, 05A20 (Secondary)

description: Let $G$ be a finite simple graph. For $X \subset V(G)$, the difference of $X$, $d(X) := |X| - |N (X)|$ where $N(X)$ is the neighborhood of $X$ and $\max \, \{d(X):X\subset V(G)\}$ is called the critical difference of $G$. $X$ is called a critical set if $d(X)$ equals the critical difference and ker$(G)$ is the intersection of all critical sets. It is known that ker$(G)$ is an independent (vertex) set of $G$. diadem$(G)$ is the union of all critical independent sets. An independent set $S$ is an inclusion minimal set with $d(S) > 0$ if no proper subset of $S$ has positive difference. A graph $G$ is called König-Egerváry if the sum of its independence number ($α(G)$) and matching number ($μ(G)$) equals $|V(G)|$. It is known that bipartite graphs are König-Egerváry. In this paper, we study independent sets with positive difference for which every proper subset has a smaller difference and prove a result conjectured by Levit and Mandrescu in 2013. The conjecture states that for any graph, the number of inclusion minimal sets $S$ with $d(S) > 0$ is at least the critical difference of the graph. We also give a short proof of the inequality $|$ker$(G)| + |$diadem$(G)| \le 2α(G)$ (proved by Short in 2016). A characterization of unicyclic non-König-Egerváry graphs is also presented and a conjecture which states that for such a graph $G$, the critical difference equals $α(G) - μ(G)$, is proved. We also make an observation about ker$G)$ using Edmonds-Gallai Structure Theorem as a concluding remark.
description: 18 pages, 2 figures
Probing Primordial-Black-Hole Dark Matter with Gravitational Waves
Creators: name: Kovetz, Ely D.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Primordial black holes (PBHs) have long been suggested as a candidate for making up some or all of the dark matter in the Universe. Most of the theoretically possible mass range for PBH dark matter has been ruled out with various null observations of expected signatures of their interaction with standard astrophysical objects. However, current constraints are significantly less robust in the 20 M_sun < M_PBH < 100 M_sun mass window, which has received much attention recently, following the detection of merging black holes with estimated masses of ~30 M_sun by LIGO and the suggestion that these could be black holes formed in the early Universe. We consider the potential of advanced LIGO (aLIGO) operating at design sensitivity to probe this mass range by looking for peaks in the mass spectrum of detected events. To quantify the background, which is due to black holes that are formed from dying stars, we model the shape of the stellar-black-hole mass function and calibrate its amplitude to match the O1 results. Adopting very conservative assumptions about the PBH and stellar-black-hole merger rates, we show that ~5 years of aLIGO data can be used to detect a contribution of >20 M_sun PBHs to dark matter down to f_PBH<0.5 at >99.9% confidence level. Combined with other probes that already suggest tension with f_PBH=1, the obtainable independent limits from aLIGO will thus enable a firm test of the scenario that PBHs make up all of dark matter.
description: 5 pages, 2 figures; expanded discussion of uncertainties; matches publication in PRL
Weighted norm inequalities for rough singular integral operators
Creators: name: Li, Kangwei
name: Pérez, Carlos
name: Rivera-Ríos, Israel P.
name: Roncal, Luz
Publisher: name: arXiv
Year: 2017
Subjects: subject: Classical Analysis and ODEs (math.CA)
subject: FOS: Mathematics

description: In this paper we provide weighted estimates for rough operators, including rough homogeneous singular integrals $T_Ω$ with $Ω\in L^\infty(\mathbb{S}^{n-1})$ and the Bochner-Riesz multiplier at the critical index $B_{(n-1)/2}$. More precisely, we prove qualitative and quantitative versions of Coifman-Fefferman type inequalities and their vector-valued extensions, weighted $A_p-A_\infty$ strong and weak type inequalities for $1
description: 29 pages, v3: minor changes
On the Gevrey regularity for Sums of Squares of vector fields, study of some models
Creators: name: Chinni, Gregorio
Publisher: name: arXiv
Year: 2017
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 35H10, 35H20, 35B65

description: The micro-local Gevrey regularity of a class of "sums of squares" with real analytic coefficients is studied in detail. Some partial regularity result is also given.
Metaphorical profiles and near-synonyms: A corpus-based study of Indonesian words for HAPPINESS
Creators: name: Rajeg, Gede Primahadi Wijaya
Publisher: name: Monash University
Year: 2019
Subjects: subject: Linguistics
subject: FOS: Languages and literature
subject: 200313 Indonesian Languages
subject: 170299 Cognitive Science not elsewhere classified
subject: FOS: Psychology
subject: Language

description: This thesis investigates metaphors for different words of happiness in Indonesian. It finds that happiness is predominantly described, among others, as an object we possess, share, and acquire; a goal one seeks to attain; a substance filling the human-body. Moreover, each of the happiness words shows statistical preferences for certain metaphors. For instance, while kebahagiaan ‘happiness’ and kesenangan ‘pleasure’ are frequently described as a desired goal, this metaphor is much less frequent for kegembiraan ‘joy’, described more frequently as a contained liquid (e.g., kegembiraan terpancar ‘joy is spurted out’). This suggests nuances between these happiness words in Indonesian.
The supplementary materials for the thesis (data and R codes for analyses) are bundled into an R package happyr (Rajeg, 2018).
Qualitative study in Loop Quantum Cosmology
Creators: name: Saló, Llibert Aresté
name: Amorós, Jaume
name: de Haro, Jaume
Publisher: name: arXiv
Year: 2016
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: This work contains a detailed qualitative analysis, in General Relativity and in Loop Quantum Cosmology, of the dynamics in the associated phase space of a scalar field minimally coupled with gravity, whose potential mimics the dynamics of a perfect fluid with a linear Equation of State (EoS). Dealing with the orbits (solutions) of the system, we will see that there are analytic ones, which lead to the same dynamics as the perfect fluid, and our goal is to check their stability, depending on the value of the EoS parameter, i.e., to show whether the other orbits converge or diverge to these analytic solutions at early and late times.
description: 12 pages, 7 figures. Version accepted for publication in CQG
Metaphorical profiles of five Indonesian quasi-synonyms of ANGER: Multiple distinctive collexeme analysis
Creators: name: Rajeg, Gede Primahadi Wijaya
Publisher: name: Monash University
Year: 2019
Subjects: subject: Linguistics
subject: FOS: Languages and literature

description: Preferable citation of the paper:

Rajeg, G. P. W. (2014). Metaphorical profiles of five Indonesian quasi-synonyms of ANGER: Multiple distinctive collexeme analysis. In Proceedings of the International Congress of the Linguistic Society of Indonesia 2014 (pp. 165-170). Bandar Lampung, Sumatra, Indonesia: Masyarakat Linguistik Indonesia (MLI). https://doi.org/10.4225/03/58578ddba1fd2

To cite this repository, click the dark pink Cite button and then select the citation style from the dropdown button. The default style is DataCite.
The presentation slides, the input raw data, and the analysis output for the Multiple Distinctive Collexeme Analysis (MDCA) are available in the earlier version (Version 3) of this repository; select it from the Version dropdown button below the title.
MDCA is performed to the input data using the Coll.analysis 3.2, an R script to conduct the variety of Collostructional Analysis.
Investigating the temperature dependence of the specific shear viscosity of QCD matter with dilepton radiation
Creators: name: Vujanovic, Gojko
name: Denicol, Gabriel S.
name: Luzum, Matthew
name: Jeon, Sangyong
name: Gale, Charles
Publisher: name: arXiv
Year: 2017
Subjects: subject: Nuclear Theory (nucl-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: This work reports on investigations of the effects on the evolution of viscous hydrodynamics and on the flow coefficients of thermal dileptons, originating from a temperature-dependent specific shear viscosity $η/s (T)$ at temperatures beyond 180 MeV formed at the Relativistic Heavy-Ion Collider (RHIC). We show that the elliptic flow of thermal dileptons can resolve the magnitude of $η/s$ at the high temperatures, where partonic degrees of freedom become relevant, whereas discriminating between different specific functional forms will likely not be possible at RHIC using this observable.
description: 25 pages, 20 figures
Metafora Emosi Bahasa Indonesia
Creators: name: Rajeg, I Made
Publisher: name: figshare
Year: 2023
Subjects: Indonesian languages
Indonesian literature
Language studies not elsewhere classified
Linguistic structures (incl. phonology, morphology and syntax)
Linguistics not elsewhere classified
Computational linguistics
Other language, communication and culture not elsewhere classified

description: This document is a booklet-length summary (in both Indonesian and English) of my Doctoral dissertation completed in 2013 at Udayana University, Indonesia. Cite this thesis as follows: In APA 6th: Rajeg, I. M. (2013). Metafora emosi Bahasa Indonesia. (Disertasi doktoral). Universitas Udayana, Denpasar, Bali, Indonesia. https://doi.org/10.6084/m9.figshare.7886180. In Unified style sheet for linguistics: Rajeg, I Made. 2013. Metafora emosi Bahasa Indonesia. Denpasar, Bali, Indonesia: Universitas Udayana Disertasi doktoral. doi:10.6084/m9.figshare.7886180. Description The thesis is a corpus-based investigation of emotion metaphors for five Indonesian words that each refers to ANGER, LOVE, FEAR, HAPPINESS, and SADNESS. The data is based on literary corpus texts downloaded from the web. The study adops quantitative corpus linguistic methods of Metaphorical Pattern Analysis (Stefanowitsch 2006). Related emotion metaphor studies in Indonesian can be seen in the References below.
Research Community Management - Skills framework
Creators: name: Sharan, Malvika
name: Karoune, Emma
Publisher: name: Zenodo
Year: 2023
Subjects: Community Management
Community
Research
Data Science
Open Research
Skills

description: This skills framework has been developed for The Alan Turing Institutes Research Community Management Team. Documents include: Research Community Management (RCM) - Team roles and responsibilities - spreadsheet Template for Case study - The Alan Turing Institute including RCM skills framework This is part of a wider project about 'Professionalising traditional and infrastructure research roles in data science'. See more information about this project at this link: https://github.com/alan-turing-institute/professionalising-data-science-roles
Does a growing static length scale control the glass transition?
Creators: name: Wyart, Matthieu
name: Cates, Michael E.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: Several theories of the glass transition propose that the structural relaxation time τα is controlled by a growing static length scale ξ that is determined by the free energy landscape but not by the local dynamical rules governing its exploration. We argue, based on recent simulations using particle-radius-swap dynamics, that only a modest factor in the increase in τα on approach to the glass transition may stem from the growth of a static length, with a vastly larger contribution attributable instead to a slowdown of local dynamics. This reinforces arguments that we base on the observed strong coupling of particle diffusion and density fluctuations in real glasses
Groups that have the same holomorph as a finite perfect group
Creators: name: Caranti, A.
name: Volta, F. Dalla
Publisher: name: arXiv
Year: 2016
Subjects: subject: Group Theory (math.GR)
subject: FOS: Mathematics
subject: 20B35, 20D45, 20D40

description: We describe the groups that have the same holomorph as a finite perfect group. Our results are complete for centerless groups. When the center is non-trivial, some questions remain open. The peculiarities of the general case are illustrated by a couple of examples that might be of independent interest.
description: 19 pages - minor revisions
Gain settings for the upgraded H.E.S.S. CT1-4 cameras under moonlight observations
Creators: name: Tomankova, Lenka
name: Yusafzai, Anke
name: Kostunin, Dmitriy
name: Giavitto, Gianluca
name: Ohm, Stefan
name: Mitchell, Alison
name: de Naurois, Mathuie
name: Lenain, Jean-Philippe
name: H. E. S. S. Collaboration
Publisher: name: Deutsches Elektronen-Synchrotron, DESY, Hamburg
Year: 2022
Subjects: instrumentation
very-high energy gamma-ray astronomy
cherenkov cameras
calibration

description: Zenodo (2022). doi:10.5281/ZENODO.7400326 special issue: "HESS technical note"
description: The purpose of this technical document is to assess the effect of a gain reduction on low- and high-level analysis results and to investigate the option of using a common lowered gain for both, dark and moonlight observations. Using a sequence of six Crab Nebula runs taken at alternating gain settings, it was shown that decreasing the gain factor from 80 to 60 Analog-to-digital counts per photo-electron (ADC/pe) has no significant effect on the telescope system sensitivity under dark-sky conditions. This result confirms expectations that such a change in gain has a comparatively small effect on the signal readout. In particular, the following results were obtained: 1. The trigger rates and event statistics are comparable for both gains. 2. The distributions of Hillas parameters are consistent for both gains. 3. The spectral analysis results are consistent within about 10%. The efficiency of detecting gamma rays is energy-independent and consistent for both gains, indicating no loss of performance at any energy.
description: Published by Zenodo
New characterizations of Ricci curvature on RCD metric measure spaces
Creators: name: Han, Bang-Xian
Publisher: name: arXiv
Year: 2017
Subjects: subject: Functional Analysis (math.FA)
subject: Analysis of PDEs (math.AP)
subject: Metric Geometry (math.MG)
subject: FOS: Mathematics
subject: Primary: 47D07, 30L99, Secondary: 51F99

description: We prove that on a large family of metric measure spaces, if the $L^p$-gradient estimate for heat flows holds for some $p>2$, then the $L^1$-gradient estimate also holds. This result extends Savaré's result on metric measure spaces, and provides a new proof to von Renesse-Sturm theorem on smooth metric measure spaces. As a consequence, we propose a new analysis object based on Gigli's measure-valued Ricci tensor, to characterize the Ricci curvature of ${\rm RCD}$ space in a local way. The argument is a new iteration technique based on non-smooth Bakry-Émery theory, which is a new method to study the curvature dimension condition of metric measure spaces.
description: The first title of this paper was `Self-improvement of gradient estimate of heat flows on metric measure spaces'
A new astrophysical solution to the Too Big To Fail problem - Insights from the MoRIA simulations
Creators: name: Verbeke, Robbert
name: Papastergis, Emmanouil
name: Ponomareva, Anastasia A.
name: Rathi, Shivangee
name: De Rijcke, Sven
Publisher: name: arXiv
Year: 2017
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We test whether advanced galaxy models and analysis techniques of simulations can alleviate the Too Big To Fail problem (TBTF) for late-type galaxies, which states that isolated dwarf galaxy kinematics imply that dwarfs live in lower-mass halos than is expected in a ΛCDM universe. Furthermore, we want to explain this apparent tension between theory and observations. To do this, we use the MoRIA suite of dwarf galaxy simulations to investigate whether observational effects are involved in TBTF for late-type field dwarf galaxies. To this end, we create synthetic radio data cubes of the simulated MoRIA galaxies and analyse their HI kinematics as if they were real, observed galaxies. We find that for low-mass galaxies, the circular velocity profile inferred from the HI kinematics often underestimates the true circular velocity profile, as derived directly from the enclosed mass. Fitting the HI kinematics of MoRIA dwarfs with a theoretical halo profile results in a systematic underestimate of the mass of their host halos. We attribute this effect to the fact that the interstellar medium of a low-mass late-type dwarf is continuously stirred by supernova explosions into a vertically puffed-up, turbulent state to the extent that the rotation velocity of the gas is simply no longer a good tracer of the underlying gravitational force field. If this holds true for real dwarf galaxies as well, it implies that they inhabit more massive dark matter halos than would be inferred from their kinematics, solving TBTF for late-type field dwarf galaxies.
description: 21 pages, 21 figures. Accepted for publication in A&A. Corrected certain values in Table 1
Anomalous Acoustic Plasmon Mode from Topologically Protected States
Creators: name: Jia, Xun
name: Zhang, Shuyuan
name: Sankar, Raman
name: Chou, Fang-Cheng
name: Wang, Weihua
name: Kempa, K.
name: Plummer, E. W.
name: Zhang, Jiandi
name: Zhu, Xuetao
name: Guo, Jiandong
Publisher: name: arXiv
Year: 2017
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Plasmons, the collective excitations of electrons in the bulk or at the surface, play an important role in the properties of materials, and have generated the field of Plasmonics. We report the observation of a highly unusual acoustic plasmon mode on the surface of a three-dimensional topological insulator (TI), Bi2Se3, using momentum resolved inelastic electron scattering. In sharp contrast to ordinary plasmon modes, this mode exhibits almost linear dispersion into the second Brillouin zone and remains prominent with remarkably weak damping not seen in any other systems. This behavior must be associated with the inherent robustness of the electrons in the TI surface state, so that not only the surface Dirac states but also their collective excitations are topologically protected. On the other hand, this mode has much smaller energy dispersion than expected from a continuous media excitation picture, which can be attributed to the strong coupling with surface phonons.
Relative entropy of steering: On its definition and properties
Creators: name: Kaur, Eneet
name: Wilde, Mark M.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: In [Gallego and Aolita, Physical Review X 5, 041008 (2015)], the authors proposed a definition for the relative entropy of steering and showed that the resulting quantity is a convex steering monotone. Here we advocate for a different definition for relative entropy of steering, based on well grounded concerns coming from quantum Shannon theory. We prove that this modified relative entropy of steering is a convex steering monotone. Furthermore, we establish that it is uniformly continuous and faithful, in both cases giving quantitative bounds that should be useful in applications. We also consider a restricted relative entropy of steering which is relevant for the case in which the free operations in the resource theory of steering have a more restricted form (the restricted operations could be more relevant in practical scenarios). The restricted relative entropy of steering is convex, monotone with respect to these restricted operations, uniformly continuous, and faithful.
description: v2: 24 pages, final version accepted for publication in Journal of Physics A
Equivariant thinning over a free group
Creators: name: Soo, Terry
name: Wilkens, Amanda
Publisher: name: arXiv
Year: 2017
Subjects: subject: Dynamical Systems (math.DS)
subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 37A35, 60G10, 60E15

description: We construct entropy increasing monotone factors in the context of a Bernoulli shift over the free group of rank at least two.
description: 14 pages. Version 2 contains minor edits and a simplification of the main theorem
Scalar Casimir effect in a high-dimensional cosmic dispiration spacetime
Creators: name: Mota, H. F.
name: de Mello, E. R. Bezerra
name: Bakke, K.
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: In this paper we present a complete and detailed analysis of the calculation of both the Wightman function and the vacuum expectation value of the energy-momentum tensor that arise from quantum vacuum fluctuations of massive and massless scalar fields in the cosmic dispiration spacetime, which is formed by the combination of two topological defects: a cosmic string and a screw dislocation. This spacetime is obtained in the framework of the Einstein-Cartan theory of gravity and is considered to be a chiral space-like cosmic string. For completeness we perform the calculation in a high-dimensional spacetime, with flat extra dimensions. We found closed expressions for the the energy-momentum tensor and, in particular, in (3+1)-dimensions, we compare our results with existing previous ones in the literature for the massless scalar field case.
description: 26 pages, 5 figures
Effect of finite particle number sampling on baryon number fluctuations
Creators: name: Steinheimer, Jan
name: Koch, Volker
Publisher: name: arXiv
Year: 2017
Subjects: subject: Nuclear Theory (nucl-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The effects of finite particle number sampling on the net baryon number cumulants, extracted from fluid dynamical simulations, are studied. The commonly used finite particle number sampling procedure introduces an additional Poissonian (or multinomial if global baryon number conservation is enforced) contribution which increases the extracted moments of the baryon number distribution. If this procedure is applied to a fluctuating fluid dynamics framework one severely overestimates the actual cumulants. We show that the sampling of so called test-particles suppresses the additional contribution to the moments by at least one power of the number of test-particles. We demonstrate this method in a numerical fluid dynamics simulation that includes the effects of spinodal decomposition due to a first order phase transition. Furthermore, in the limit where anti-baryons can be ignored, we derive analytic formulas which capture exactly the effect of particle sampling on the baryon number cumulants. These formulas may be used to test the various numerical particle sampling algorithms.
description: 9 pages 3 figures
Profile of solutions for nonlocal equations with critical and supercritical nonlinearities
Creators: name: Bhakta, Mousomi
name: Mukherjee, Debangana
name: Santra, Sanjiban
Publisher: name: arXiv
Year: 2016
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: We study the fractional laplacian problem (-Δ)^s u &=& u^p -εu^q \quad\text{in }\quad Ω, u &\in& H^s(Ω)\cap L^{q+1}(Ω),u &>&0 \quad\text{in }\quad Ω, u&=&0 \quad\text{in}\quad \mathbb{R}^N\setminusΩ, where $s\in(0,1)$, $q>p\geq \frac{N+2s}{N-2s}$ and $ε>0$ is a parameter. Here $Ω\subseteq\mathbb{R}^N$ is a bounded star-shaped domain with smooth boundary and $N> 2 s$. We establish existence of a variational positive solution $u_ε$ and characterize the asymptotic behaviour of $u_ε$ as $ε\to 0$. When $p=\frac{N+2s}{N-2s}$, we describe how the solution $u_ε$ concentrates and blows up at a interior point of the domain. Furthermore, we prove the local uniqueness of solution of the above problem when $Ω$ is a convex symmetric domain of $\mathbb{R}^N$ with $N>4s$ and $p=\frac{N+2s}{N-2s}$.
description: 30 pages
Implications and Impacts of Connected and Autonomous vehicles (CAVs) on Employment and Job Market Disruption
Creators: name: Ahmad, Miraj Uddin
Publisher: name: figshare
Year: 2023
Subjects: classificationCode: 350501
subject: Business and labour history
classificationCode: 350502
subject: Employment equity and diversity

description: This report is part of the author's MSc Fintech course module (at the University of Huddersfield) named - Artificial Intelligence. AbstractConnected and Autonomous Vehicles (CAVs), an emerging technology in the transport and logistics industry, is on the verge of stepping into the smart cities of mankind with the aim of revolutionising transportation. Since no revolution, however, tends to come up without a hitch, CAVs are not an exception. Resulting in fear of potential mass destruction of jobs in and around the transportation industry. This paper, through review of available literatures in this field, argues that primarily it would, mostly, be the lower skilled driving professionals to encounter the side effects of this technological revolution (i.e., mass redundancies) while the highly skilled professionals plausibly see diverse range of career opportunities. Moreover, underprivileged jobseekers of rural areas, and workers commuting from distant places likely to experience the benefits of this multi-modal mobility service which could ensure equal access in employment opportunities subject to an impeccable policy formation and implementation for CAVs by the policymakers. The paper also interprets the perception of future users of CAVs while suggesting that, for the purpose of gaining public acceptance towards CAVs introduction and mitigating the aftermath of potential mass unemployment, government should not delay in initiating awareness campaign, promoting research & innovation in CAVs and early reskilling & training of the existing workforce.
Quasiparticle Interference of Surface States in Type-II Weyl Semimetal WTe$_2$
Creators: name: Zhang, Wenhan
name: Wu, Quansheng
name: Zhang, Lunyong
name: Cheong, Sang-Wook
name: Soluyanov, Alexey A.
name: Wu, Weida
Publisher: name: arXiv
Year: 2017
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Topological Weyl semimetal (TWS) is a metal, where low energy excitations behave like Weyl fermions of high-energy physics. It was recently shown that due to the lower symmetry of condensed matter systems, they can realize two distinct types of Weyl fermions. The type-I Weyl fermion in a metal is formed by a linear crossing of two bands at a point in the crystalline momentum space - Brillouin zone (BZ). The second type TWSs host type-II Weyl points appearing at the touching points of electron and hole pockets, which is a result of tilted linear dispersion. The type-II TWS was predicted to exist in several compounds, including WTe$_2$. Several ARPES studies of WTe$_2$ were reported so far, having contradictory conclusions on the topological nature of observed Fermi arcs. In this work, we report the results of spectroscopic imaging with a scanning tunneling microscope and first principle calculations, establishing a clear quasiparticle interference features of the surface states of WTe$_2$. Our work provides a strong evidence for surface state scattering. Although the surface Fermi arcs are clearly observed, it is still difficult to prove the existence of predicted Type-II Weyl points in the bulk.
description: 11 pages, 3 figures
Variational cluster approach to superconductivity and magnetism in the Kondo lattice model
Creators: name: Lenz, Benjamin
name: Gezzi, Riccardo
name: Manmana, Salvatore R.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We investigate in detail antiferromagnetic (AF) and superconducting (SC) phases as well as their coexistence in the two-dimensional Kondo lattice model on a square lattice, which is a paradigmatic model for heavy fermion materials. The results presented are mainly obtained using the variational cluster approximation (VCA) and are complemented by analytical findings for the equations of motion of pairing susceptibilities. A particularly interesting aspect is the possibility to have s-wave SC near half filling as reported by Bodensiek \textit{et al.} [Phys. Rev. Lett. \textbf{110}, 146406 (2013)]. When doping the system, we identify three regions which correspond to an AF metallic phase with small Fermi surface at weak coupling, an AF metal with a different Fermi surface topology at intermediate coupling, and a paramagnetic metal with a large Fermi surface at strong coupling. The transition between these two AF phases is found to be discontinuous at lower fillings, but turns to a continuous one when approaching half-filling. In the quest for s-wave superconductivity, only solutions are found which possess mean-field character. No true superconducting solutions caused by correlation effects are found in the s-wave channel. In contrast, we clearly identify robust d-wave pairing away from half-filling. However, we show that only by treating antiferromagnetism and superconductivity on equal footing artificial superconducting solutions at half-filling can be avoided. Our VCA findings support scenarios previously identified by variational Monte Carlo approaches and are a starting point for future investigations with VCA and further approaches such as cluster-embedding methods.
description: 19(+8) pages, 18(+7) figures; v3: final version
Open Science in den Geschichtswissenschaften? Konzeption eines offenen Forschungsdatenmanagements am Beispiel von Forschungsdaten zu Jüdischen Gewerbebetrieben im Nationalsozialismus (Masterarbeit)
Creators: name: Eckenstaler, Sophie
Publisher: name: Zenodo
Year: 2022
Subjects: open science
open data
research data management
historical reseach data

description: Abschlussarbeit im Masterstudiengang Geschichtswissenschaften mit Schwerpunkt Digital History an der Humboldt-Universität zu Berlin, eingereicht am 07.06.2022
description: If you use this dataset, please cite it using the metadata from this file.
Tomographically reconstructed master equations for any open quantum dynamics
Creators: name: Pollock, Felix A.
name: Modi, Kavan
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Memory effects in open quantum dynamics are often incorporated in the equation of motion through a superoperator known as the memory kernel, which encodes how past states affect future dynamics. However, the usual prescription for determining the memory kernel requires information about the underlying system-environment dynamics. Here, by deriving the transfer tensor method from first principles, we show how a memory kernel master equation, for any quantum process, can be entirely expressed in terms of a family of completely positive dynamical maps. These can be reconstructed through quantum process tomography on the system alone, either experimentally or numerically, and the resulting equation of motion is equivalent to a generalised Nakajima-Zwanzig equation. For experimental settings, we give a full prescription for the reconstruction procedure, rendering the memory kernel operational. When simulation of an open system is the goal, we show how our procedure yields a considerable advantage for numerically calculating dynamics, even when the system is arbitrarily periodically (or transiently) driven or initially correlated with its environment. Namely, we show that the long time dynamics can be efficiently obtained from a set of reconstructed maps over a much shorter time.
description: 10+4 pages, 5 figures
Soft Gravitons & the Memory Effect for Plane Gravitational Waves
Creators: name: Zhang, P. -M.
name: Duval, C.
name: Gibbons, G. W.
name: Horvathy, P. A.
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The "gravitational memory effect" due to an exact plane wave provides us with an elementary description of the diffeomorphisms associated with soft gravitons. It is explained how the presence of the latter may be detected by observing the motion of freely falling particles or other forms of gravitational wave detection. Numerical calculations confirm the relevance of the first, second and third time integrals of the Riemann tensor pointed out earlier. Solutions for various profiles are constructed. It is also shown how to extend our treatment to Einstein-Maxwell plane waves and a midi-superspace quantization is given.
description: 40 pages, many figures. Matches published version
IFZ news Herbst/Winter 2008
Creators: name: (:Unkn) Unknown
name: Justus Liebig University Giessen
Publisher: name: Universitätsbibliothek Gießen
Year: 2008
Subjects: subject: ddc:630

description: "Giessener Modell" auch in Albanien erfolgreich -*Stadtgespräch Gentechnik -*Regulatorische Netzwerke und die innere Uhr von Bakterien -*Pflanzenzüchterische und populationsgenetische Systeme -*Ein zartes Pflänzchen macht sich breit -*Tools für EU-weites Risikomanagement im Pflanzenschutz -*Tierökologie startet EU-Verbundvorhaben SOILSERVICE -*Biosphere IFZ Schwanenblume und Krebsschere im IFZ-Teich.
Supplementary Information from The 2013 Chikungunya outbreak in the Caribbean was structured by the network of cultural relationships among islands
Creators: name: Dommar, Carlos J.
name: López, Leonardo
name: Paul, Richard
name: Rodó, Xavier
Publisher: name: The Royal Society
Year: 2023
Subjects: Health Care
Diseases
Epidemiology
Mathematical Sciences not elsewhere classified
Simulation and Modelling

description: In 2013, the Caribbean underwent an unprecedented epidemic of Chikungunya that affected 29 islands and mainland territories throughout the Caribbean in the first six months. Analysing the spread of the epidemic among the Caribbean islands, we show that the initial patterns of the epidemic can be explained by a network model based on the flight connections among islands. The network does not follow a random graph model and its topology is likely the product of geo-political relationships that generate increased connectedness among locations sharing the same language. Therefore, the infection propagated preferentially among islands that belong to the same cultural domain, irrespective of their human and vector population densities. Importantly, the flight network topology was also a more important determinant of the disease dynamics than the actual volume of traffic. Finally, the severity of the epidemic was found to depend, in the first instance, on which island was initially infected. This investigation shows how a simple epidemic model coupled with an appropriate human mobility model can reproduce the observed epidemiological dynamics. Also, it sheds light on the design of interventions in the face of the emergence of infections in similar settings of naive subpopulations loosely interconnected by host movement. This study delves into the feasibility of developing models to anticipate the emergence of vector-borne infections, showing the importance of network topology, bringing valuable methods for public health officials when planning control policies.