cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Rigorous justification for the space-split sensitivity algorithm to compute linear response in Anosov systems
Creators: name: Chandramoorthy, Nisha
name: Jézéquel, Malo
Publisher: name: arXiv
Year: 2021
Subjects: subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics
subject: 37C30

description: Ruelle gave a formula for linear response of transitive Anosov diffeomorphisms. Recently, practically computable realizations of Ruelle's formula have emerged that potentially enable sensitivity analysis of certain high-dimensional chaotic numerical simulations encountered in the applied sciences. In this paper, we provide full mathematical justification for the convergence of one such efficient computation, the space-split sensitivity, or S3, algorithm. In S3, Ruelle's formula is computed as a sum of two terms obtained by decomposing the perturbation vector field into a coboundary and a remainder that is parallel to the unstable direction. Such a decomposition results in a splitting of Ruelle's formula that is amenable to efficient computation. We prove the existence of the S3 decomposition and the convergence of the computations of both resulting components of Ruelle's formula.
description: v2: added case of higher dimensional unstable manifolds v3: fixed some mistakes, improvements in the exposition v4: Electronic copy of final peer-reviewed manuscript accepted for publication
Tube-Certified Trajectory Tracking for Nonlinear Systems With Robust Control Contraction Metrics
Creators: name: Zhao, Pan
name: Lakshmanan, Arun
name: Ackerman, Kasey
name: Gahlawat, Aditya
name: Pavone, Marco
name: Hovakimyan, Naira
Publisher: name: arXiv
Year: 2021
Subjects: subject: Systems and Control (eess.SY)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: This paper presents an approach towards guaranteed trajectory tracking for nonlinear control-affine systems subject to external disturbances based on robust control contraction metrics (CCM) that aims to minimize the $\mathcal L_\infty$ gain from the disturbances to nominal-actual trajectory deviations. The guarantee is in the form of invariant tubes, computed offline and valid for any nominal trajectories, in which the actual states and inputs of the system are guaranteed to stay despite disturbances. Under mild assumptions, we prove that the proposed robust CCM (RCCM) approach yields tighter tubes than an existing approach based on CCM and input-to-state stability analysis. We show how the RCCM-based tracking controller together with tubes can be incorporated into a feedback motion planning framework to plan safe trajectories for robotic systems. Simulation results illustrate the effectiveness of the proposed method and empirically demonstrate reduced conservatism compared to the CCM-based approach.
description: Extended version of a paper published in IEEE Robotics and Automation Letters (2022). 13 pages, 6 figures
Widening the Ocean:
Creators: name: Rodrigues, José Damião
Publisher: name: Leipziger Universitätsverlag
Year: 2016

description: Über Jahrhunderte hinweg spielten Inseln als „natürliche Brücken“ eine entscheidende Rolle bei der Verbindung von Ozeanen und Weltregionen. Manche nahmen eine „zentrale“, andere eine mehr „periphere“ Rolle für Schifffahrtswege und Handelsnetzwerke, die Kontrolle der Meere und die Besiedlung von Kontinenten ein. Die Konstruktion und Integration der atlantischen Welt nahm seit dem 15. Jahrhundert ihren Ausgang von den Makaronesischen Inseln, die den Mittelmeerraum mit dem Atlantischen Becken verbanden. Auf den Kanaren, Madeira, den Azoren und Kapverdischen Inseln, aber auch auf São Tomé und Príncipe wurden traditionell mediterrane, soziale und ökonomische Muster an neue geographische und historische Kontexte angepasst. Dabei bildeten sich Prototypen der nachfolgenden Kolonisierung Amerikas heraus. Der Beitrag betrachtet die frühneuzeitliche ostatlantische Welt als frühen Schauplatz der europäischen „Moderne.“
description: Comparativ, Vol 26 No 5 (2016): The Baltic Sea: A Space of Changing Expectations
The Gauss-Bonnet topological scalar in the Geometric Trinity of Gravity
Creators: name: Bajardi, Francesco
name: Blixt, Daniel
name: Capozziello, Salvatore
Publisher: name: arXiv
Year: 2023
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The Gauss-Bonnet topological scalar is presented in metric-teleparallel formalism as well as in the symmetric and general teleparallel formulations. In all of the aforementioned frameworks, the full expressions are provided explicitly in terms of torsion, non-metricity and Levi-Civita covariant derivative. The number of invariant terms of this form is counted and compared with the number which can appear in the corresponding effective field theory. Although the difference in this number is not very large, it is found that the Gauss-Bonnet invariant excludes some of the effective field theory terms. This result sheds new light on how General Relativity symmetries can be maintained at higher order in teleparallel theories: this fact appears to be highly nontrivial in the teleparallel formulation. The importance of the so-called ``pseudo-invariant'' theories like $f(T)$- and $f(T,T_\mathcal{G})$-gravity is further discussed in the context of teleparallel Gauss-Bonnet gravity.
description: 18 pages; Accepted for publication in IJGMMP
Convex-Concave Min-Max Stackelberg Games
Creators: name: Goktas, Denizalp
name: Greenwald, Amy
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computer Science and Game Theory (cs.GT)
subject: Machine Learning (cs.LG)
subject: Numerical Analysis (math.NA)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: Min-max optimization problems (i.e., min-max games) have been attracting a great deal of attention because of their applicability to a wide range of machine learning problems. Although significant progress has been made recently, the literature to date has focused on games with independent strategy sets; little is known about solving games with dependent strategy sets, which can be characterized as min-max Stackelberg games. We introduce two first-order methods that solve a large class of convex-concave min-max Stackelberg games, and show that our methods converge in polynomial time. Min-max Stackelberg games were first studied by Wald, under the posthumous name of Wald's maximin model, a variant of which is the main paradigm used in robust optimization, which means that our methods can likewise solve many convex robust optimization problems. We observe that the computation of competitive equilibria in Fisher markets also comprises a min-max Stackelberg game. Further, we demonstrate the efficacy and efficiency of our algorithms in practice by computing competitive equilibria in Fisher markets with varying utility structures. Our experiments suggest potential ways to extend our theoretical results, by demonstrating how different smoothness properties can affect the convergence rate of our algorithms.
description: 25 pages, 4 tables, 1 figure, Forthcoming in NeurIPS 2021
Spaces of Belonging and Intra-European Migration from Southern and Eastern Periphery to the North
Creators: name: Petrogiannis, Vasileios
Publisher: name: Leipziger Universitätsverlag
Year: 2016

description: Vor dem Hintergrund erneut wachsender Migrationsströme innerhalb der EU wertet der Autor Interviews aus, die er in Schweden mit Migranten aus Griechenland und Lettland geführt hat. Dabei geht es ihm darum, zu verstehen, wie sich die EU-Bürgerschaft auf die Identifikation mit nationalen, regionalen und europäischen Räumen auswirkt. Es zeigt sich, dass die nationale die wichtigste Ebene der Selbstidentifikation bleibt. „Europäisch“ zu sein wird ebenfalls als wichtig erachtet, zumal es im Immigrationsland einen Zugang zu Rechten garantiert, der Dritten verwehrt bleibt. Im Fall lettischer Migranten wird eine regionale Zugehörigkeit zum Baltikum und Osteuropa definiert, die von Skandinavien und Westeuropa abgegrenzt bleibt. Die griechischen Befragten sehen sich mehr zum Balkan denn zum Mittelmeer gehörig, von dessen nichteuropäischen Anrainern sie sich distanzieren möchten. Als Einheiten gedachte Mittelmeer- und Ostseeregionen spielen für die Erwartungen der Migranten kaum eine Rolle.
description: Comparativ, Vol 26 No 5 (2016): The Baltic Sea: A Space of Changing Expectations
A tunable electronic beam splitter realized with crossed graphene nanoribbons
Creators: name: Brandimarte, Pedro
name: Engelund, Mads
name: Papior, Nick
name: Garcia-Lekue, Aran
name: Frederiksen, Thomas
name: Sánchez-Portal, Daniel
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Graphene nanoribbons (GNRs) are promising components in future nanoelectronics due to the large mobility of graphene electrons and their tunable electronic band gap in combination with recent experimental developments of on-surface chemistry strategies for their growth. Here we explore a prototype 4-terminal semiconducting device formed by two crossed armchair GNRs (AGNRs) using state-of-the-art first-principles transport methods. We analyze in detail the roles of intersection angle, stacking order, inter-GNR separation, and finite voltages on the transport characteristics. Interestingly, when the AGNRs intersect at $θ= 60^\circ$, electrons injected from one terminal can be split into two outgoing waves with a tunable ratio around 50% and with almost negligible back-reflection. The splitted electron wave is found to propagate partly straight across the intersection region in one ribbon and partly in one direction of the other ribbon, i.e., in analogy of an optical beam splitter. Our simulations further identify realistic conditions for which this semiconducting device can act as a mechanically controllable electronic beam splitter with possible applications in carbon-based quantum electronic circuits and electron optics. We rationalize our findings with a simple model that suggests that electronic beam splitters can generally be realized with crossed GNRs.
Localization effects from local phase shifts in the modulation of waveguide arrays
Creators: name: Tschernig, Konrad
name: Perez-Leija, Armando
name: Busch, Kurt
Publisher: name: arXiv
Year: 2023
Subjects: subject: Optics (physics.optics)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Artificial gauge fields enable the intriguing possibility to manipulate the propagation of light as if it were under the influence of a magnetic field even though photons possess no intrinsic electric charge. Typically, such fields are engineered via periodic modulations of photonic lattices such that the effective coupling coefficients after one period become complex-valued. In this work, we investigate the possibility to introduce randomness into artificial gauge fields by applying local random phase shifts in the modulation of lattices of optical waveguides. We first study the elemental unit consisting of two coupled single-mode waveguides and determine the effective complex-valued coupling coefficient after one period of the modulation as a function of the phase shift, the modulation amplitude and the modulation frequency. Thereby we identify the regime where varying the modulation phase yields sufficiently large changes of the effective coupling coefficient to induce Anderson localization. Using these results, we demonstrate numerically the onset of Anderson localization in 1D- and 2D-lattices of x-, and helically-modulated waveguides via randomly choosing the modulation phases of the individual waveguides. Besides further fundamental investigations of wave propagation in the presence of random gauge fields, our findings enable the engineering of the coupling coefficients without changing the footprint of the overall lattice. As a proof of concept, we demonstrate how to engineer out-of-phase modulated lattices which exhibit dynamic localization and defect-free surface states. Therefore, we anticipate that the modulation phase will play an important role in the judicious design of functional waveguide lattices.
Optimizing floating guard ring designs for FASPAX N-in-P silicon sensors
Creators: name: Shin, Kyung-Wook
name: Bradford, Robert
name: Lipton, Ronald
name: Deptuch, Gregory
name: Fahim, Farah
name: Madden, Tim
name: Zimmerman, Tom
Publisher: name: arXiv
Year: 2016
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: FASPAX (Fermi-Argonne Semiconducting Pixel Array X-ray detector) is being developed as a fast integrating area detector with wide dynamic range for time resolved applications at the upgraded Advanced Photon Source (APS.) A burst mode detector with intended $\mbox{13 $MHz$}$ image rate, FASPAX will also incorporate a novel integration circuit to achieve wide dynamic range, from single photon sensitivity to $10^{\text{5}}$ x-rays/pixel/pulse. To achieve these ambitious goals, a novel silicon sensor design is required. This paper will detail early design of the FASPAX sensor. Results from TCAD optimization studies, and characterization of prototype sensors will be presented.
description: IEEE NSS-MIC 2015 Conference record
Challenges of Transnational Regional Democracy:
Creators: name: Kurunmäki, Jussi
Publisher: name: Leipziger Universitätsverlag
Year: 2016

description: Der 1991 gegründeten Ostseeparlamentarierkonferenz (BSPC) wurde eine wichtige Rolle für die Demokratisierung transnationaler Entscheidungsprozesse im Ostseeraum zugeschrieben. Erwartet wurde, dass sie zur Herausbildung einer regionalen Zivilgesellschaft und politischen Öffentlichkeit beitragen könne. Der Autor untersucht die Arbeit der BSPC in Hinblick auf erfüllte und unerfüllte Erwartungen. Die Theorien der transnationalen Demokratie fanden in diesem Fall keine Bestätigung, da die BSCP-Mitglieder die Interessen ihrer nationalen Wahlkreise in den Vordergrund stellten. Auch in dieser Institution konnte demnach das nationalstaatliche Paradigma nicht zugunsten einer politisch integrierten „Ostseeregion“ überwunden werden. Angesichts der Spannungen mit dem mittlerweile einzigen Nicht-EU-Mitglied der BSPC, Russland, kann die Parlamentarierkonferenz jedoch im Rahmen herkömmlicher zwischenstaatlicher Kooperation zu Frieden und Sicherheit in der Region beitragen.
description: Comparativ, Vol 26 No 5 (2016): The Baltic Sea: A Space of Changing Expectations
Petals and Books: The largest Laplacian spectral gap from 1
Creators: name: Jost, Jürgen
name: Mulas, Raffaella
name: Zhang, Dong
Publisher: name: arXiv
Year: 2021
Subjects: subject: Combinatorics (math.CO)
subject: Spectral Theory (math.SP)
subject: FOS: Mathematics

description: We prove that, for any connected graph on $N\geq 3$ vertices, the spectral gap from the value $1$ with respect to the normalized Laplacian is at most $1/2$. Moreover, we show that equality is achieved if and only if the graph is either a petal graph (for $N$ odd) or a book graph (for $N$ even). This implies that $(\frac12,\frac32)$ is a maximal gap interval for the normalized Laplacian on connected graphs. This is closely related to the Alon-Boppana bound on regular graphs and a recent result by Kollár and Sarnak on cubic graphs. Our result also provides a sharp bound for the convergence rate of some eigenvalues of the Laplacian on neighborhood graphs.
description: 32 pages
From Isolation to Connectivity?
Creators: name: Paci, Deborah
Publisher: name: Leipziger Universitätsverlag
Year: 2016

description: In Ostsee und Mittelmeer spielen Inseln eine wichtige Rolle bei der Umsetzung europäischer makroregionaler Strategien. Der Aufsatz untersucht, wie die EU an die Probleme von Inseln herangeht. Bis zu den Verträgen von Maastricht (1992) und Amsterdam (1997) wurden sie im Struktur- und regionalpolitischen Rahmen kaum beachtet. Seit die Insellage als gesondertes Problem anerkannt wird, bemisst die EU die „dauerhaften strukturellen Nachteile“ von Inseln fast ausschließlich an ihrer Entfernung vom nationalen Festland. Demgegenüber haben die Island Studies der letzten Jahrzehnte unter Verweis auf die die Vielseitigkeit der Außenverflechtung von Inseln eine stärker Insel- und Netzwerkzentrierte Sichtweise gefordert. Wie die Autorin unterstreicht, schmälert das Beharren der EU auf einem Festlandzentrierten Ansatz das Potential, das durch den stärkeren Ausbau von Inselnetzwerken zur Geltung gebracht werden könnte.
description: Comparativ, Vol 26 No 5 (2016): The Baltic Sea: A Space of Changing Expectations
Strategies of offence and defence in takeover battles in Australia
Creators: name: Jones, Brian Farquhar.
Publisher: name: Monash University
Year: 2022

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
Space of Failed Expectations?
Creators: name: Grzechnik, Marta
Publisher: name: Leipziger Universitätsverlag
Year: 2016

description: Nach dem Fall des Eisernen Vorhangs richteten sich viele Bemühungen darauf, die Ostseeregion als einheitlich gestaltete und gelebte Region zu etablieren. Politische und akademische Akteure arbeiteten gezielt und nicht ohne Erfolg an der Verbreitung grenzüberwindender Kategorien. Dies geschah nicht nur theoretisch, sondern auch praktisch in dem Sinne, dass sich grenzübergreifende Netzwerke herausgebildet haben, in denen der Transfer von Ideen bezüglich der „Ostseeregion“ reibungslos funktioniert. Die nähere Untersuchung dieser und anderer im 20. Jh. gegründeter Netzwerke zeigt allerdings, dass sie oft nicht die ganze Region umspannen, über die sie reden und die sie erreichen möchten. Der vorliegende Beitrag beschäftigt sich mit den Grenzen der Übertragbarkeit von Ideen über die „Ostseeregion“ und stellt sich der Herausforderung, diese Grenzen zu erklären und zu verstehen.
description: Comparativ, Vol 26 No 5 (2016): The Baltic Sea: A Space of Changing Expectations
Fast approximate delivery of fluence maps: the VMAT case
Creators: name: Balvert, Marleen
name: Craft, David
Publisher: name: arXiv
Year: 2016
Subjects: subject: Medical Physics (physics.med-ph)
subject: FOS: Physical sciences

description: In this article we provide a method to generate the trade-off between delivery time and fluence map matching quality for volumetric modulated arc therapy (VMAT). At the heart of our method lies a mathematical programming model that, for a given duration of delivery, optimizes leaf trajectories and dose rates such that the desired fluence map is reproduced as well as possible. This model was presented for the single map case in a companion paper (Fast approximate delivery of fluence maps: the single map case). The resulting large-scale, non-convex optimization problem was solved using a heuristic approach. The single-map approach cannot directly be applied to the full arc case due to the large increase in model size, the issue of allocating delivery times to each of the arc segments, and the fact that the ending leaf positions for one map will be the starting leaf positions for the next map. In this article the method proposed in \cite{dm1} is extended to solve the full map treatment planning problem. We test our method using a prostate case and a head and neck case, and present the resulting trade-off curves. Analysis of the leaf trajectories reveal that short time plans have larger leaf openings in general than longer delivery time plans. Our method allows one to explore the continuum of possibilities between coarse, large segment plans characteristic of direct aperture approaches and narrow field plans produced by sliding window approaches. Exposing this trade off will allow for an informed choice between plan quality and solution time. Further research is required to speed up the optimization process to make this method clinically implementable.
Analysis of pressure-robust embedded-hybridized discontinuous Galerkin methods for the Stokes problem under minimal regularity
Creators: name: Baier-Reinio, Aaron
name: Rhebergen, Sander
name: Wells, Garth N.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics
subject: 65N12, 65N15, 65N30, 76D07

description: We present analysis of two lowest-order hybridizable discontinuous Galerkin methods for the Stokes problem, while making only minimal regularity assumptions on the exact solution. The methods under consideration have previously been shown to produce $H(\textrm{div})$-conforming and divergence-free approximate velocities. Using these properties, we derive a priori error estimates for the velocity that are independent of the pressure. These error estimates, which assume only $H^{1+s}$-regularity of the exact velocity fields for any $s \in [0, 1]$, are optimal in a discrete energy norm. Error estimates for the velocity and pressure in the $L^2$-norm are also derived in this minimal regularity setting. Our theoretical findings are supported by numerical computations.
Towards the Distribution of a Class of Polycrystalline Materials with an Equilibrium Defect Structure by Grain Diameters: Temperature Behavior of the Yield Strength
Creators: name: Reshetnyak, Alexander A.
name: Shamshutdinova, Varvara V.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences
subject: J.2
subject: 62P35 74C05 74C10 74C15 74C20 74E15

description: We modify a theory of flow stress introduced in [arXiv:1803.08247[cond-mat.mtrl-sci]], [arXiv:1809.03628[cond-mat.mes-hall]], [arXiv:1908.09338[cond-mat.mtrl-sci]] for a class of polycrystalline materials with equilibrium and quasy-equilibrium defect structure under quasi-static plastic deformations. We suggest, in addition to modified Bose-Einstein distribution, Maxwell-like distribution law for defects (within dislocation-disclination mechanism) in the grains of polycrystalline samples with respect to grain's diameter. Polycrystalline aggregates are considered within single- and two-phase models that correspond to the presence of crystalline and grain-boundary (porous) phases. The scalar dislocation density is derived. Analytic and graphic forms of the generalized Hall-Petch relations for yield strength are produced for single-mode samples with BCC ($α$-Fe), FCC (Cu, Al, Ni) and HCP ($α$-Ti, Zr) crystal lattices at T=300 K with different values of the grain-boundary phase. We derived new form of the temperature-dimensional effect. The values of extremal grain and maximum of yield strength are decreased with raising the temperature in accordance with experiments up to NC region.
description: 8 pages, 1 figure, 2 tables, contribution to the Proceedings of the International Conference Physical mesomechanics of condensed matter: Physical principles of multiscale structure formation and the mechanisms of nonlinear behavior, 5-8, September, 2022, Tomsk, Russia
Deliverable 1.2 Inequality concepts and theories in the postcrisis Europe Summary of the literature review-revised version
Creators: name: University Of Uppsala
name: Metropolitan Research Institute
name: University Of Tartu
name: Tárki Társadalomkutatási Intézet Zrt
name: CESIS
name: Technical University Of Delft
Publisher: name: Zenodo
Year: 2021
Subjects: social inequality
economic theories
precarious work
young people
welfare regime
education
labour market
housing
urban regimes
capability approach
life-course analysis
intergenerational mobility
vulnerability

description: This report sums up key social science concepts, theories, and debates related to inequality supporting the scientific design of UPLIFT.
Region Building Around the Baltic Sea, 1989–2016:
Creators: name: Petri, Rolf
Publisher: name: Leipziger Universitätsverlag
Year: 2016

description: Nach 1989 wurden hohe Erwartungen in die Neubegründung des Ostseeraums als Geschichtsregion gesetzt. Den Bürgern der Anrainerstaaten sollten damit neue Möglichkeiten geboten werden, sich mit übernationalen politischen Prozessen und dem ungehinderten Austausch über alle Grenzen hinweg zu identifizieren. Die hier versammelten Beiträge würdigen die durch die EU-Erweiterung erzielten Ergebnisse, ziehen jedoch hinsichtlich der anvisierten Etablierung einer „Ostseeregion“ eine eher ernüchternde Bilanz. Teils im Vergleich mit dem Mittelmeerraum werden die Strukturpolitik für Inseln, die Bemühungen um Demokratisierung der transnationalen Politik, die intellektuellen Anstrengungen zur Verankerung der Großregion sowie deren Wahrnehmung durch Migranten untersucht. Dabei zeigt sich, dass nationale Interessen und Erwartungshorizonte sowie ältere Raumvorstellungen der Etablierung einer „Ostseeregion“ bisher entgegenstehen.
description: Comparativ, Vol 26 No 5 (2016): The Baltic Sea: A Space of Changing Expectations
Convergence to weak solutions of a space-time hybridized discontinuous Galerkin method for the incompressible Navier--Stokes equations
Creators: name: Kirk, Keegan L. A.
name: Çeşmelioǧlu, Ayçıl
name: Rhebergen, Sander
Publisher: name: arXiv
Year: 2021
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics
subject: 65M12, 65M60, 76D05, 35Q30

description: We prove that a space-time hybridized discontinuous Galerkin method for the evolutionary Navier--Stokes equations converges to a weak solution as the time step and mesh size tend to zero. Moreover, we show that this weak solution satisfies the energy inequality. To perform our analysis, we make use of discrete functional analysis tools and a discrete version of the Aubin--Lions--Simon theorem.
Ferroelastic toughening: can it solve the mechanics challenges of solid electrolytes?
Creators: name: Van der Ven, Anton
name: McMeeking, Robert M.
name: Clément, Raphaële J.
name: Garikipati, Krishna
Publisher: name: arXiv
Year: 2023
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The most promising solid electrolytes for all-solid-state Li batteries are oxide and sulfide ceramics. Current ceramic solid electrolytes are brittle and lack the toughness to withstand the mechanical stresses of repeated charge and discharge cycles. Solid electrolytes are susceptible to crack propagation due to dendrite growth from Li metal anodes and to debonding processes at the cathode/electrolyte interface due to cyclic variations in the cathode lattice parameters. In this perspective, we argue that solutions to the mechanics challenges of all-solid-state batteries can be borrowed from the aerospace industry, which successfully overcame similar hurdles in the development of thermal barrier coatings of superalloy turbine blades. Their solution was to exploit ferroelastic and transformation toughening mechanisms to develop ceramics that can withstand cyclic stresses due to large variations in temperature. This perspective describes fundamental materials design principles with which to search for solid electrolytes that are ferroelastically toughened.
description: 8 pages, 8 figures
Around the combinatorial unit ball of measured foliations on bordered surfaces
Creators: name: Borot, Gaëtan
name: Charbonnier, Séverin
name: Delecroix, Vincent
name: Giacchetto, Alessandro
name: Wheeler, Campbell
Publisher: name: arXiv
Year: 2021
Subjects: subject: Geometric Topology (math.GT)
subject: Combinatorics (math.CO)
subject: Differential Geometry (math.DG)
subject: FOS: Mathematics

description: The volume $\mathscr{B}_Σ^{\rm comb}(\mathbb{G})$ of the unit ball -- with respect to the combinatorial length function $\ell_{\mathbb{G}}$ -- of the space of measured foliations on a stable bordered surface $Σ$ appears as the prefactor of the polynomial growth of the number of multicurves on $Σ$. We find the range of $s \in \mathbb{R}$ for which $(\mathscr{B}_Σ^{\rm comb})^{s}$, as a function over the combinatorial moduli spaces, is integrable with respect to the Kontsevich measure. The results depends on the topology of $Σ$, in contrast with the situation for hyperbolic surfaces where Arana-Herrera and Athreya (arXiv:1907.06287) recently proved an optimal square-integrability.
description: 37 pages, 2 appendices. v2: typos corrected, pictures added, and explanations added in various places
Mutual information for symmetric rank-one matrix estimation: A proof of the replica formula
Creators: name: Barbier, Jean
name: Dia, Mohamad
name: Macris, Nicolas
name: Krzakala, Florent
name: Lesieur, Thibault
name: Zdeborova, Lenka
Publisher: name: arXiv
Year: 2016
Subjects: subject: Information Theory (cs.IT)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Machine Learning (cs.LG)
subject: Mathematical Physics (math-ph)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: Factorizing low-rank matrices has many applications in machine learning and statistics. For probabilistic models in the Bayes optimal setting, a general expression for the mutual information has been proposed using heuristic statistical physics computations, and proven in few specific cases. Here, we show how to rigorously prove the conjectured formula for the symmetric rank-one case. This allows to express the minimal mean-square-error and to characterize the detectability phase transitions in a large set of estimation problems ranging from community detection to sparse PCA. We also show that for a large set of parameters, an iterative algorithm called approximate message-passing is Bayes optimal. There exists, however, a gap between what currently known polynomial algorithms can do and what is expected information theoretically. Additionally, the proof technique has an interest of its own and exploits three essential ingredients: the interpolation method introduced in statistical physics by Guerra, the analysis of the approximate message-passing algorithm and the theory of spatial coupling and threshold saturation in coding. Our approach is generic and applicable to other open problems in statistical estimation where heuristic statistical physics predictions are available.
From Western History to Miscellaneous History and Memory Activism in Postcolonial Korea – An Interview with Jie-Hyun Lim
Creators: name: Lim, Jie-Hyun
Publisher: name: Leipziger Universitätsverlag
Year: 2016

description: Comparativ, Vol 26 No 6 (2016): Ideas of Empire after the First World War: Redefining Identity and Citizenship in Colonial Empires
Differentiable Retrieval Augmentation via Generative Language Modeling for E-commerce Query Intent Classification
Creators: name: Zhao, Chenyu
name: Jiang, Yunjiang
name: Qiu, Yiming
name: Zhang, Han
name: Yang, Wen-Yun
Publisher: name: arXiv
Year: 2023
Subjects: subject: Information Retrieval (cs.IR)
subject: Computation and Language (cs.CL)
subject: FOS: Computer and information sciences
subject: H.3.3

description: Retrieval augmentation, which enhances downstream models by a knowledge retriever and an external corpus instead of by merely increasing the number of model parameters, has been successfully applied to many natural language processing (NLP) tasks such as text classification, question answering and so on. However, existing methods that separately or asynchronously train the retriever and downstream model mainly due to the non-differentiability between the two parts, usually lead to degraded performance compared to end-to-end joint training. In this paper, we propose Differentiable Retrieval Augmentation via Generative lANguage modeling(Dragan), to address this problem by a novel differentiable reformulation. We demonstrate the effectiveness of our proposed method on a challenging NLP task in e-commerce search, namely query intent classification. Both the experimental results and ablation study show that the proposed method significantly and reasonably improves the state-of-the-art baselines on both offline evaluation and online A/B test.
description: 5 pages, 2 figures; accepted by CIKM2023
Cubature Method for Stochastic Volterra Integral Equations
Creators: name: Feng, Qi
name: Zhang, Jianfeng
Publisher: name: arXiv
Year: 2021
Subjects: subject: Probability (math.PR)
subject: Numerical Analysis (math.NA)
subject: Mathematical Finance (q-fin.MF)
subject: FOS: Mathematics
subject: FOS: Economics and business
subject: 60H20, 65C30, 91G60

description: In this paper, we introduce the cubature formula for Stochastic Volterra Integral Equations. We first derive the stochastic Taylor expansion in this setting, by utilizing a functional Itô formula, and provide its tail estimates. We then introduce the cubature measure for such equations, and construct it explicitly in some special cases, including a long memory stochastic volatility model. We shall provide the error estimate rigorously. Our numerical examples show that the cubature method is much more efficient than the Euler scheme, provided certain conditions are satisfied.
description: Published version
Optical potential for incident and emitted low-energy $α$ particles. III. Non-statistical processes induced by neutrons on Zr, Nb, and Mo nuclei
Creators: name: Avrigeanu, Marilena
name: Avrigeanu, Vlad
Publisher: name: arXiv
Year: 2023
Subjects: subject: Nuclear Theory (nucl-th)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: The reliability of a previous $α$-particle optical-model potential (OMP) on nuclei with mass number 45$\leq$$A$$\leq$209 was proved for emitted $α$ particles as well, for proton--induced reactions on Zn isotopes [Phys. Rev. C {\bf 91}, 064611 (2015), Paper I]. However, the same was not the case of neutrons on Zr stable isotopes [Phys. Rev. C {\bf 96}, 044610 (2017), Paper II]. A recent assessment of this potential also for nucleon--induced $α$-emission on $A$$\sim$60 nuclei, including pickup direct reaction and eventual Giant Quadrupole Resonance (GQR) $α$-emission, is completed for neutrons incident on Zr, Nb, and Mo stable isotopes. Consistent sets of input parameters, determined through analysis of independent data, is involved while no further empirical rescaling factors of the $γ$ and nucleon widths have been involved. A suitable account of all competitive reaction channels is confirmed by careful uncertainty analysis, to avoid parameter ambiguities and/or error compensation. Additional validation of this potential is also supported by recently measured $(α,γ)$ and $(α,n)$ cross--sections of Zr and Mo nuclei. An increase of the $α$-emission beyond the statistical predictions, through consideration of additional reaction channels of the pickup direct interaction and {\it like}--GQR decay, makes possible the description of both absorption and emission of $α$ particles by the same optical potential.
description: 21 pages, 16 figures
Quantum heat waves in a one-dimensional condensate
Creators: name: Agarwal, Kartiek
name: Torre, Emanuele G. Dalla
name: Schmiedmayer, Jörg
name: Demler, Eugene
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: We study the dynamics of phase relaxation between a pair of one-dimensional condensates created by a bi-directional, supersonic `unzipping' of a finite single condensate. We find that the system fractures into different \emph{extensive} chunks of space-time, within which correlations appear thermal but correspond to different effective temperatures. Coherences between different eigen-modes are crucial for understanding the development of such thermal correlations; at no point in time can our system be described by a generalized Gibbs' ensemble despite nearly always appearing locally thermal. We rationalize a picture of propagating fronts of hot and cold sound waves, populated at effective, relativistically red- and blue-shifted temperatures to intuitively explain our findings. The disparity between these hot and cold temperatures vanishes for the case of instantaneous splitting but diverges in the limit where the splitting velocity approaches the speed of sound; in this limit, a sonic boom occurs wherein the system is excited only along an infinitely narrow, and infinitely hot beam. We expect our findings to apply generally to the study of superluminal perturbations in systems with emergent Lorentz symmetry.
description: 12+epsilon pages + Refs., 8 figures
Towards The Ultimate Brain: Exploring Scientific Discovery with ChatGPT AI
Creators: name: Adesso, Gerardo
Publisher: name: arXiv
Year: 2023
Subjects: subject: Other Computer Science (cs.OH)
subject: FOS: Computer and information sciences

description: This paper presents a novel approach to scientific discovery using an artificial intelligence (AI) environment known as ChatGPT, developed by OpenAI. This is the first paper entirely generated with outputs from ChatGPT. We demonstrate how ChatGPT can be instructed through a gamification environment to define and benchmark hypothetical physical theories. Through this environment, ChatGPT successfully simulates the creation of a new improved model, called GPT$^4$, which combines the concepts of GPT in AI (generative pretrained transformer) and GPT in physics (generalized probabilistic theory). We show that GPT$^4$ can use its built-in mathematical and statistical capabilities to simulate and analyze physical laws and phenomena. As a demonstration of its language capabilities, GPT$^4$ also generates a limerick about itself. Overall, our results demonstrate the promising potential for human-AI collaboration in scientific discovery, as well as the importance of designing systems that effectively integrate AI's capabilities with human intelligence.
description: 26 pages. To appear in AI Magazine
Higgs bosons production and decay at future $e^+e^-$ linear colliders as a probe of the B-L model
Creators: name: Ramirez-Sanchez, F.
name: Gutierrez-Rodriguez, A.
name: Hernandez-Ruiz, M. A.
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We study the phenomenology of the light and heavy Higgs boson production and decay in the context of a $U(1)_{B-L}$ extension of the Standard Model with an additional $Z'$ boson at future $e^+e^-$ linear colliders with center-of-mass energies of $\sqrt{s}=500-3000\hspace{0.8mm}GeV$ and integrated luminosities of ${\cal L}=500-2000\hspace{0.8mm}fb^{-1}$. The study includes the processes $e^{+}e^{-}\rightarrow (Z, Z') \to Zh$ and $e^{+}e^{-}\rightarrow (Z, Z') \to ZH$, considering both the resonant and non-resonant effects. We find that the total number of expected $Zh$ and $ZH$ events can reach 909,124 and 97,487, respectively, which is a very optimistic scenario and thus it would be possible to perform precision measurements for both Higgs bosons $h$ and $H$, as well as for the $Z'$ boson in future high-energy and high-luminosity $e^+e^-$ colliders experiments. Our study complements other studies on the B-L model and on the Higgs-strahlung processes $e^{+}e^{-}\rightarrow (Z, Z') \to Zh$ and $e^{+}e^{-}\rightarrow (Z, Z') \to ZH$.
description: 39 pages, 15 figures; To be published in The Journal of Physics G: Nuclear and Particle Physics. arXiv admin note: substantial text overlap with arXiv:1506.07575; text overlap with arXiv:1106.4462 by other authors
Optical transitions in two-dimensional topological insulators with point defects
Creators: name: Sablikov, Vladimir A.
name: Sukhanov, Aleksei A.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Nontrivial properties of electronic states in topological insulators are inherent not only to the surface and boundary states, but to bound states localized at structure defects as well. We clarify how the unusual properties of the defect-induced bound states are manifested in optical absorption spectra in two-dimensional topological insulators. The calculations are carried out for defects with short-range potential. We find that the defects give rise to the appearance of specific features in the absorption spectrum, which are an inherent property of topological insulators. They have the form of two or three absorption peaks that are due to intracenter transitions between electron-like and hole-like bound states.
description: 7 pages, 3 figures
Impacts of outdoor recreation on space-use, behaviour and interspecific interactions of red deer (Cervus elaphus) in the Scottish Highlands
Creators: name: Marion, Solène
Publisher: name: University of St Andrews
Year: 2022
Subjects: Red deer
Hikers
Spatio-temporal interactions
Outdoor activities
Camera traps

description: In Scotland, the geographical distribution of red deer (Cervus elaphus scoticus) overlaps with areas used for popular outdoor activities such as hill walking. This overlap can have multiple consequences for the animal but also for its successful management. Here, I study the impact of hiking activity on red deer spatio-temporal distribution, behaviour, and interaction with sheep. First, to study the impact of hiker activity on deer detection and on their behaviour, camera traps were placed in transects at different distances (25, 75 and 150m) from the hiking path. Hiking activity was monitored and classified as busy or quiet. Second, to study how hiking activity influenced red deer interaction with sheep, camera traps were distributed at various distances from the hiking path. I found that red deer spatial and temporal response occurred at less than 150m, as more red deer were detected at 150m than at 25m. During the day, red deer were detected at greater rates in an isolated area relative to areas close to the hiking path. This avoidance only occurred on a short temporal scale, as deer returned to areas close to the hiking path the following night. I did not detect an increase in vigilance or flight behaviour closer to the hiking path or during busy hiking activity. However, the interaction between sheep and deer changed with distance from the hiking path, with greater spatial and temporal overlap in areas further away from the hiking path. I conclude that (i) hikers impact the spatial distribution of red deer at distances smaller than 150m but that this impact is only of short duration temporal scale, (ii) hiking activity does not have a significant impact on the behaviour of the animal, and (iii) hiking activity may influence the interaction between sheep and deer.
Gender, Empire and Citizenship Issues:
Creators: name: Donati, Sabina
Publisher: name: Leipziger Universitätsverlag
Year: 2016

description: Diese Sammelbesprechung untersucht eine Auswahl an einschlägigen Werken, die sich mit den kaum zu trennenden Themenfeldern Gender, Empire und Staatsangehörigkeit innerhalb der italienischen Kolonialerfahrung auseinandersetzen. Der Untersuchungszeitraum umfasst die 1920er und 190er Jahre, mit vereinzelten Rückblenden in die vorausgehenden liberalen Jahrzehnte. Es werden insbesondere Veröffentlichungen in italienischer und englischer Sprache besprochen, um darin vorkommende Forschungstraditionen und akademische Debatten herauszuheben die sich mit dem italienischen Fall beschäftigen. Diese werden wiederum vergleichend betrachtet und in Relation zu der etablierten Forschung zum britischen und französischen Imperialismus gesetzt, zu der sie Ähnlichkeiten, aber auch Unterschiede aufweisen.
description: Comparativ, Vol 26 No 6 (2016): Ideas of Empire after the First World War: Redefining Identity and Citizenship in Colonial Empires
Why do some cores remain starless ?
Creators: name: Anathpindika, S.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Physical conditions that could render a core starless(in the local Universe) is the subject of investigation in this work. To this end we studied the evolution of four starless cores, B68, L694-2, L1517B, L1689, and L1521F, a VeLLO. The density profile of a typical core extracted from an earlier simulation developed to study core-formation in a molecular cloud was used for the purpose. We demonstrate - (i) cores contracted in quasistatic manner over a timescale on the order of $\sim 10^{5}$ years. Those that remained starless did briefly acquire a centrally concentrated density configuration that mimicked the density profile of a unstable Bonnor Ebert sphere before rebounding, (ii) three of our test cores viz. L694-2, L1689-SMM16 and L1521F remained starless despite becoming thermally super-critical. On the contrary B68 and L1517B remained sub-critical; L1521F collapsed to become a VeLLO only when gas-cooling was enhanced by increasing the size of dust-grains. This result is robust, for other cores viz. B68, L694-2, L1517B and L1689 that previously remained starless could also be similarly induced to collapse. Our principle conclusions are : (a) acquiring the thermally super-critical state does not ensure that a core will necessarily become protostellar, (b) potentially star-forming cores (VeLLO L1521F here), could be experiencing coagulation of dust-grains that must enhance the gas-dust coupling and in turn lower the gas temperature, thereby assisting collapse. This hypothesis appears to have some observational support, and (c) depending on its dynamic state at any given epoch, a core could appear to be pressure-confined, gravitationally/virially bound, suggesting that gravitational/virial boundedness of a core is insufficient to ensure it will form stars, though it is crucial for gas in a contracting core to cool efficiently so it can collapse further to become protostellar.
description: 10 Figures, 3 Tables; To appear in the Publications of the Australian Society of Astronomy
Synchronization and Fundamental Time: a Connection between Relativity and Quantum Mechanics
Creators: name: Ruggiero, Matteo Luca
Publisher: name: arXiv
Year: 2023
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: An interesting connection between special relativity and quantum mechanics was put forward by Louis de Broglie, about 60 years ago, who focused on the link between synchronization in a rotating frame and the quantization of the angular momentum. Here we generalise his approach to curved spacetime, using the gravitoelectromagnetic analogy, which can be applied to describe the weak gravitational field around rotating sources, and give a new interpretation of the results.
description: 11 pages; accepted for publication in Foundations of Physics
Kinetic small angle neutron scattering of the Skyrmion lattice in MnSi
Creators: name: Mühlbauer, S.
name: Kindervater, J.
name: Adams, T.
name: Bauer, A.
name: Keiderling, U.
name: Pfleiderer, C.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We report a kinetic small angle neutron scattering study of the skyrmion lattice (SL) in MnSi. Induced by an oscillatory tilting of the magnetic field direction, the elasticity and relaxation of the SL along the magnetic field direction have been measured with microsecond resolution. For the excitation frequency of 325 Hz the SL begins to track the tilting motion of the applied magnetic field under tilting angles exceeding $α_c$ > 0.4°. Empirically the associated angular velocity of the tilting connects quantitatively with the critical charge carrier velocity of approx. 0.1mm/s under current driven spin transfer torques, for which the SL unpins. In addition, a pronounced temperature dependence of the skyrmion motion is attributed to the variation of the skyrmion stiffness. Taken together our study highlights the power of kinetic small angle neutron scattering as a new experimental tool to explore, in a rather general manner, the elasticity and impurity pinning of magnetic textures across a wide parameter space without parasitic signal interferences due to ohmic heating or Oersted magnetic fields.