cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Stability and asymptotic interactions of chiral magnetic skyrmions in a tilted magnetic field
Creators: name: Barton-Singer, Bruno
name: Schroers, Bernd J.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: 70S20

description: Using a general framework, interaction potentials between chiral magnetic solitons in a planar system with a tilted external magnetic field are calculated analytically in the limit of large separation. The results are compared to previous numerical results for solitons with topological charge $\pm 1$. A key feature of the calculation is the interpretation of Dzyaloshinskii-Moriya interaction (DMI) as a background $SO(3)$ gauge field. In a tilted field, this leads to a $U(1)$-gauged version of the usual equation for spin excitations, leading to a distinctive oscillating interaction profile. We also obtain predictions for skyrmion stability in a tilted field which closely match numerical observations.
description: Updated to the final version published in SciPost Physics. Small change to notation to distinguish between the abstract gauge field $\boldsymbol{A}_i$ and the concrete DMI parameters of a given magnet $\boldsymbol{D}_i$. No other significant changes
Resolved imaging of exoplanets with the solar gravitational lens
Creators: name: Turyshev, Slava G.
name: Toth, Viktor T.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We discuss the feasibility of direct multipixel imaging of exoplanets with the solar gravitational lens (SGL) in the context of a realistic deep space mission. For this, we consider an optical telescope, placed in the image plane that forms in the strong interference region of the SGL. We consider an Earth-like exoplanet located in our immediate stellar neighborhood and model its characteristics using our own Earth. We estimate photon fluxes from such a compact, extended, resolved exoplanet. This light appears in the form of an Einstein ring around the Sun, seen through the solar corona. The solar corona background contributes a significant amount of stochastic noise and represents the main noise source for observations utilizing the SGL. We estimate the magnitude of this noise. We compute the resulting signal-to-noise ratios (SNRs) and related integration times that are needed to perform imaging measurements under realistic conditions. It is known that deconvolution, removing the blur due to the SGL's spherical aberration substantially decreases the SNR. Our key finding is that this "penalty" is significantly mitigated when sampling locations in the image plane (image pixels) remain widely spaced. Consequently, we conclude that an imaging mission is challenging but feasible, using technologies that are either already available or in active development. Under realistic conditions, high-resolution imaging of Earth-like exoplanets in our galactic neighborhood requires only weeks or months of integration time, not years as previously thought: a high quality 1000x1000 pixel image of an Earth-like planet at Proxima Centauri could be obtained with SNR>10 using approximately 14 months of integration time.
description: 12 pages, 4 figures, 2 tables
Renormalization Group Study of a Fragile Fermi liquid in $1+ε$ dimensions
Creators: name: Mai, Peizhi
name: Krishnamurthy, H. R.
name: Shastry, B. Sriram
Publisher: name: arXiv
Year: 2016
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We present a calculation of the low energy Greens function in $1+ε$ dimensions using the method of extended poor man's scaling, developed here. We compute the wave function renormalization $Z(ω)$ and also the decay rate near the Fermi energy. Despite the lack of $ω^2$ damping characteristic of 3-dimensional Fermi liquids, we show that quasiparticles do exist in $1+ε$ dimensions, in the sense that the quasiparticle weight $Z$ is finite and that the damping rate is smaller than the energy. We explicitly compute the crossover from this behavior to a 1-dimensional type Tomonaga-Luttinger liquid behavior at higher energies.
Leveraging Reinforcement Learning for Task Resource Allocation in Scientific Workflows
Creators: name: Bader, Jonathan
name: Zunker, Nicolas
name: Becker, Soeren
name: Kao, Odej
Publisher: name: arXiv
Year: 2022
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: FOS: Computer and information sciences

description: Scientific workflows are designed as directed acyclic graphs (DAGs) and consist of multiple dependent task definitions. They are executed over a large amount of data, often resulting in thousands of tasks with heterogeneous compute requirements and long runtimes, even on cluster infrastructures. In order to optimize the workflow performance, enough resources, e.g., CPU and memory, need to be provisioned for the respective tasks. Typically, workflow systems rely on user resource estimates which are known to be highly error-prone and can result in over- or underprovisioning. While resource overprovisioning leads to high resource wastage, underprovisioning can result in long runtimes or even failed tasks. In this paper, we propose two different reinforcement learning approaches based on gradient bandits and Q-learning, respectively, in order to minimize resource wastage by selecting suitable CPU and memory allocations. We provide a prototypical implementation in the well-known scientific workflow management system Nextflow, evaluate our approaches with five workflows, and compare them against the default resource configurations and a state-of-the-art feedback loop baseline. The evaluation yields that our reinforcement learning approaches significantly reduce resource wastage compared to the default configuration. Further, our approaches also reduce the allocated CPU hours compared to the state-of-the-art feedback loop by 6.79% and 24.53%.
description: Paper accepted in 2022 IEEE International Conference on Big Data Workshop BPOD 2022
Optimization of the green chemistry-like extraction of phenolic compounds from grape (Vitis labrusca L.) and blackberry (Rubus fruticosus L.) seeds with concomitant biological and antioxidant activity assessments
Creators: name: Junior, Tufy Kabbas
name: de Moura, Cristiane
name: Cruz, Thiago Mendanha
name: Marques, Mariza Boscacci
name: do Carmo, Mariana  Araújo Vieira
name: Turnes Pasini Deolindo, Carolina
name: Daguer, Heitor
name: Azevedo, Luciana
name: Granato, Daniel
Publisher: name: University of Limerick
Year: 2023
Subjects: classificationCode: 31
subject: Biological sciences
subject: FOS: Biological sciences

description: The objective of this work was to determine the phenolic composition, chemical and cellular antioxidant activity, cytotoxicity in human cells, and peroxidative inhibition of the defatted fraction of grape (Vitis labrusca) and blackberry (Rubus fruticosus) seeds. Soxhlet extraction (Sox) was used to extract the fat and obtain the degreased material. A statistical optimization study was developed to maximize the extraction of bioactive compounds and antioxidant activity from defatted grape and blackberry seeds. Simultaneous optimization was applied with a combination of 35.9 min of extraction and a solid-to-solvent ratio of 1 g of defatted grape seed to 61.28 mL of an extracting solvent (60% ethanol) and 62.1 min of extraction and a solid-to-solvent ratio of 1 g of defatted blackberry seed to 64.1 mL of an extracting solvent (60% ethanol). In the cell viability assay, HepG2 cancer cells seemed more sensitive to grape and blackberry extracts, while Ea.hy926 hybrid cells showed more resistance to their effects. In general, the extracts presented low/no cytotoxicity, exhibited a protective effect against H2O2 -induced ROS production, and demonstrated antioxidant activity and a protective effect on the erythrocytes when subjected to hypotonic and isotonic conditions not presenting hemolytic behavior (5.0 to 10.0 µg GAE/mL). Thus, the results provided a broad assessment of the bioactivity of the extracts obtained using a simple and low-cost process developed by employing non-toxic solvents and with the potential to be used in technological applications.
A Model of Vector-like Leptons for the Muon $g-2$ and the $W$ Boson Mass
Creators: name: Lee, Hyun Min
name: Yamashita, Kimiko
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We consider a simple extension of the Standard Model (SM) with a vector-like lepton and a local $U(1)'$ symmetry, motivated by the recent experimental anomalies in the muon $g-2$ and the $W$ boson mass. The $U(1)'$ symmetry is spontaneously broken by the VEVs of the dark Higgs scalar and the second Higgs doublet, giving rise to the mixing between the muon and the vector-like lepton. As a result, we obtain the desirable corrections to the muon $g-2$ and the $W$ boson mass simultaneously, dominantly due to the $Z'$ gauge interactions for the vector-like lepton and the second Higgs doublet, respectively. We also discuss the consistency of the model with the $Z$ boson decay width, the Higgs couplings and the dilepton bounds.
description: 18 pages, 4 figures, v2: references and discussion on dilepton bounds added, v3: version to be published in Eur. Phys. J. C
Studies on the degradation of aggrecan from cartilage
Creators: name: Tuck., Mok Meng
Publisher: name: Monash University
Year: 2021

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.
Towards Advanced Monitoring for Scientific Workflows
Creators: name: Bader, Jonathan
name: Witzke, Joel
name: Becker, Soeren
name: Lößer, Ansgar
name: Lehmann, Fabian
name: Doehler, Leon
name: Vu, Anh Duc
name: Kao, Odej
Publisher: name: arXiv
Year: 2022
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: FOS: Computer and information sciences

description: Scientific workflows consist of thousands of highly parallelized tasks executed in a distributed environment involving many components. Automatic tracing and investigation of the components' and tasks' performance metrics, traces, and behavior are necessary to support the end user with a level of abstraction since the large amount of data cannot be analyzed manually. The execution and monitoring of scientific workflows involves many components, the cluster infrastructure, its resource manager, the workflow, and the workflow tasks. All components in such an execution environment access different monitoring metrics and provide metrics on different abstraction levels. The combination and analysis of observed metrics from different components and their interdependencies are still widely unregarded. We specify four different monitoring layers that can serve as an architectural blueprint for the monitoring responsibilities and the interactions of components in the scientific workflow execution context. We describe the different monitoring metrics subject to the four layers and how the layers interact. Finally, we examine five state-of-the-art scientific workflow management systems (SWMS) in order to assess which steps are needed to enable our four-layer-based approach.
description: Paper accepted in 2022 IEEE International Conference on Big Data Workshop SCDM 2022
Properties of IR selected Active Galactic Nuclei
Creators: name: Bornancini, Carlos G.
name: Oio, Gabriel A.
name: Alonso, M. Victoria
name: Lambas, Diego García
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Context. Active galactic nuclei (AGN) of galaxies play an important role in the life and evolution of galaxies due to the impact they exert on certain properties and the evolutionary path of galaxies. It is well known that infrared (IR) emission is useful for selecting galaxies with AGNs, although it has been observed that there is contamination by star-forming galaxies. Aims. In this work we investigate galaxy properties hosting AGNs identified at mid and near-IR wavelengths. The sample of AGNs selected at IR wavelengths was confirmed using optical spectroscopy and X-ray photometry. We study the near-UV, optical, near and mid-IR (MIR) properties, as well as [O III] λ5007 luminosity, black hole mass and morphology properties of optical and IR colour selected AGNs. Methods. We selected AGN candidates using two mid-IR colour selection techniques, a power-law emission method and a combination of mid and near-IR selection techniques. We confirm the AGN selection with two line diagnostic diagrams that use the ratio [O III]/H\b{eta} and the emission line width σ [O III] (kinematics-excitation diagram, KEx) and the host galaxy stellar mass (mass-excitation diagram, MEx), as well as X-ray photometry. Results. According to the diagnostic diagrams, the methods with the greatest success in selecting AGNs are those that use a combination of a mid and near-IR selection technique and a power-law emission. The method that use a combination of mid and near-IR observation selects a large number of AGNs, and is reasonably efficient in both the success rate (61%) and total number of AGN recovered. We also find that the KEx method presents contamination of SF galaxies within the AGN selection box. According to morphological studies based on the Sérsic index, AGN samples have higher percentages of galaxy morphologies with bulge+disk components compared to galaxies without AGNs.
description: 18 pages, 17 figures, 7 tables. Accepted for publication in Astronomy and Astrophysics (A&A)
ZH production in gluon fusion at NLO in QCD
Creators: name: Chen, Long
name: Davies, Joshua
name: Heinrich, Gudrun
name: Jones, Stephen P.
name: Kerner, Matthias
name: Mishima, Go
name: Schlenk, Johannes
name: Steinhauser, Matthias
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We present fully differential next-to-leading order results for Higgs production in association with a $Z$ boson in gluon fusion. Our two-loop virtual contributions are evaluated numerically using sector decomposition, including full top-quark mass effects, and supplemented at high $p_T$ by an analytic high-energy expansion to order ($m_Z^4, m_H^4, m_t^{32}$). Using the expanded results we also present a study of the top-quark mass scheme uncertainty at large $p_T$.
description: 20 pages, 8 figures
Quantum vacuum effects on the formation of black holes
Creators: name: Shafiee, Moslem
name: Bahrampour, Yousef
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We study the backreaction of quantum fields induced through the vacuum polarization and the conformal anomaly on the collapse of a thin shell of dust. It is shown that the final fate of the collapse process depends on the physical properties of the shell, including its rest and gravitational masses. Investigating the conditions for the formation of black holes, we notice that quantum effects modify the geometry and structure of Schwarzschild space-time in such a way that black holes have two horizons, an inner and an outer horizon. If the gravitational mass of the shell is about that of an ordinary star, then in most cases, the semi-classical collapse will terminate in a singularity, and in general, quantum fluctuations are not strong enough to prevent the creation of the singularity. Although under certain conditions, it is possible to form a non-singular black hole, i.e., a regular black hole. In this way, the collapse stops at a radius much larger than the Planck length below the inner horizon, and the shell bounces and starts an expansion.
description: 17 pages, 3 figures
Rhizoclonium minutissimum P. C. Silva
Creators: name: Ichihara, Kensuke
name: Shimada, Satoshi
name: Miyaji, Kazuyuki
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Plantae
Chlorophyta
Ulvophyceae
Cladophorales
Cladophoraceae
Rhizoclonium
Rhizoclonium minutissimum

description: Rhizoclonium minutissimum (Zeller) P. C. Silva (Figs. 7, 8)
 Basionym: Cladophora minutissima Zeller 1873, Algae collected by S. Kurz in Arracan and British Burma, determined and systematically arranged by G. Zeller. Journal of the Asiatic Society of Bengal 42 (2): 175–193.
 Type locality: Elephant Point, Pegu, Burma (Silva et al. 1996: 785).
description: Published as part of Ichihara, Kensuke, Shimada, Satoshi & Miyaji, Kazuyuki, 2016, Two new green algae, Rhizoclonium fractum sp. nov. and R. umbraticum sp. nov., from tropical and subtropical brackish waters of Japan, pp. 231-249 in Phytotaxa 266 (4) on page 246, DOI: 10.11646/phytotaxa.266.4.1, http://zenodo.org/record/13658104
Molecular characterization of the genes-encoding the E2 subunit of Pyruvate Dehydrogenase complex, the major autoantigen of primary biliary cirrhosis
Creators: name: Moehario., Lucky Hartati
Publisher: name: Monash University
Year: 2021

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.
Anomalous U(1) Gauge Bosons and String Physics at the Forward Physics Facility
Creators: name: Anchordoqui, Luis A.
name: Antoniadis, Ignatios
name: Benakli, Karim
name: Lust, Dieter
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We show that experiments at the Forward Physics Facility, planned to operate near the ATLAS interaction point during the LHC high-luminosity era, will be able to probe predictions of Little String Theory by searching for anomalous U(1) gauge bosons living in the bulk. The interaction of the abelian broken gauge symmetry with the Standard Model is generated at the one-loop level through kinetic mixing with the photon. Gauge invariant generation of mass for the U(1) gauge boson proceeds via the Higgs mechanism in spontaneous symmetry breaking, or else through anomaly-cancellation appealing to Stueckelberg-mass terms. We demonstrate that FASER2 will be able to probe string scales over roughly two orders of magnitude: 10^5 < M_s/TeV < 10^7.
description: Matching version to be published in PLB (addendum to arXiv:2007.11697)
Transport Implementation of the Bernstein-Vazirani Algorithm with Ion Qubits
Creators: name: Fallek, Spencer
name: Herold, Creston
name: McMahon, Brian
name: Maller, Kara
name: Brown, Kenneth
name: Amini, Jason
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Physics (quant-ph)
subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: Using trapped ion quantum bits in a scalable microfabricated surface trap, we perform the Bernstein-Vazirani algorithm. Our architecture relies upon ion transport and can readily be expanded to larger systems. The algorithm is demonstrated using two- and three-ion chains. For three ions, an improvement is achieved compared to a classical system using the same number of oracle queries. For two ions and one query, we correctly determine an unknown bit string with probability 97.6(8)%. For three ions, we succeed with probability 80.9(3)%.
Carbon-enhanced metal-poor stars in different environments
Creators: name: Salvadori, Stefania
name: Skuladottir, Asa
name: de Bennassuti, Matteo
Publisher: name: arXiv
Year: 2015
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The origin of carbon-enhanced metal-poor (CEMP) stars and their possible connections with the chemical elements produced by the first stellar generations is still highly debated. We briefly review observations of CEMP stars in different environments (Galactic stellar halo, ultra-faint and classical dwarf galaxies) and interpret their properties using cosmological chemical-evolution models for the formation of the Local Group. We discuss the implications of current observations for the properties of the first stars, clarify why the fraction of carbon-enhanced to carbon-normal stars varies in dwarf galaxies with different luminosity, and discuss the origin of the first CEMP(-no) star found in the Sculptor dwarf galaxy.
description: 4 pages, 4 figures. To appear in Astronomische Nachrichten, special issue "Reconstructing the Milky Way's History: Spectroscopic Surveys, Asteroseismology and Chemodynamical Models", Guest Editors C. Chiappini, J. Montalban, and M. Steffen, AN 2016 (in press)
Extra $W$-Boson Mass from a D3-Brane
Creators: name: Heckman, Jonathan J.
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Motivated by the recent CDF measurement of the $W$-boson mass, we study string-based particle physics models which can accommodate this deviation from the Standard Model. We consider an F-theory GUT in which the visible sector is realized on intersecting 7-branes, and extra sector states arise from a probe D3-brane near an E-type Yukawa point. The D3-brane worldvolume naturally realizes a strongly coupled sector which mixes with the Higgs. In the limit where some extra sector states get their mass solely from Higgs vevs, this leads to a contribution to the $ρ$ parameter which is too large, but as the D3-brane is separated from the 7-brane stack, this effect is suppressed, leading to O(1) - O(10) TeV scale extra sector states and a correction to $ρ$ which would be in accord with the CDF result. We also estimate the contribution to the oblique electroweak parameter $S$, and find that it is compatible with existing constraints. This also leads to additional signatures, including diphoton resonances (as well as other diboson final states) in the O(1) - O(10) TeV range.
description: v2: 12 pages, 2 figures, typos corrected, references added, clarifications added
Constraints on galactic wind models
Creators: name: Meiksin, Avery
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Observational implications are derived for two standard models of supernovae-driven galactic winds: a freely expanding steady-state wind and a wind sourced by a self-similarly expanding superbubble including thermal heat conduction. It is shown that, for the steady-state wind, matching the measured correlation between the soft x-ray luminosity and star formation rate of starburst galaxies is equivalent to producing a scaled wind mass-loading factor relative to the star-formation rate of 0.5 - 3, in agreement with the amount inferred from metal absorption line measurements. The match requires the asymptotic wind velocity v_inf to scale with the star formation rate SFR (in solar masses per year) approximately as v_inf ~ (700 - 1000) km/s SFR^{1/6}. The corresponding mass injection rate is close to the amount naturally provided by thermal evaporation from the wall of a superbubble in a galactic disc, suggesting thermal evaporation may be a major source of mass-loading. The predicted mass-loading factors from thermal evaporation within the galactic disc alone, however, are somewhat smaller, 0.2 - 2, so that a further contribution from cloud ablation or evaporation may be required. Both models may account for the 1.4GHz luminosity of unresolved radio sources within starburst galaxies for plausible parameters describing the distribution of relativistic electrons. Further observational tests to distinguish the models are suggested.
description: 16 pages, 8 figures; modified version of submission to MNRAS
Exact extreme value statistics at mixed order transitions
Creators: name: Bar, Amir
name: Majumdar, Satya N.
name: Schehr, Gregory
name: Mukamel, David
Publisher: name: arXiv
Year: 2016
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Probability (math.PR)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We study extreme value statistics (EVS) for spatially extended models exhibiting mixed order phase transitions (MOT). These are phase transitions which exhibit features common to both first order (discontinuity of the order parameter) and second order (diverging correlation length) transitions. We consider here the truncated inverse distance squared Ising (TIDSI) model which is a prototypical model exhibiting MOT, and study analytically the extreme value statistics of the domain lengths. The lengths of the domains are identically distributed random variables except for the global constraint that their sum equals the total system size $L$. In addition, the number of such domains is also a fluctuating variable, and not fixed. In the paramagnetic phase, we show that the distribution of the largest domain length $l_{\max}$ converges, in the large $L$ limit, to a Gumbel distribution. However, at the critical point (for a certain range of parameters) and in the ferromagnetic phase, we show that the fluctuations of $l_{\max}$ are governed by novel distributions which we compute exactly. Our main analytical results are verified by numerical simulations.
description: 25 pages, 6 figures, 1 table
Geometric phase assisted enhancement of non-inertial cavity-QED effects
Creators: name: Arya, Navdeep
name: Mittal, Vikash
name: Lochan, Kinjalk
name: Goyal, Sandeep K.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: The state of a quantum system acquires a phase factor, called the geometric phase, when taken around a closed trajectory in the parameter space, which depends only on the geometry of the parameter space. Due to its sensitive nature, the geometric phase is instrumental in capturing weak effects such as the acceleration-induced non-inertial quantum field theoretic effects. In this paper, we study the geometric phase response of a circularly rotating detector inside an electromagnetic cavity. Using the cavity, the non-inertial contribution to the geometric phase can be isolated from or strengthened relative to the inertial contribution. We show that the accumulative nature of the geometric phase may facilitate the experimental observation of the resulting, otherwise feeble, non-inertial contribution to the modified field correlations inside the cavity. Specifically, we show that the atom acquires an experimentally detectable geometric phase at accelerations of the order of $\sim 10^{7}$ m/s$^2$ which is experimentally feasible.
description: 8 pages, 4 figures
Intramolecular Structural Heterogeneity altered by Long-range Contacts in an Intrinsically Disordered Protein
Creators: name: Koren, Gil
name: Meir, Sagi
name: Holschuh, Lennard
name: Mertens, Haydyn D. T.
name: Ehm, Tamara
name: Yahalom, Nadav
name: Golombek, Adina
name: Schwartz, Tal
name: Svergun, Dmitri I.
name: Saleh, Omar A.
name: Dzubiella, Joachim
name: Beck, Roy
Publisher: name: arXiv
Year: 2022
Subjects: subject: Biological Physics (physics.bio-ph)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: Short-range interactions and long-range contacts drive the 3D folding of structured proteins. The proteins' structure has a direct impact on their biological function. However, nearly 40% of the eukaryotes proteome is composed of intrinsically disordered proteins (IDPs) and protein regions that fluctuate between ensembles of numerous conformations. Therefore, to understand their biological function, it is critical to depict how the structural ensemble statistics correlate to the IDPs' amino acid sequence. Here, using small-angle x-ray scattering (SAXS) and time-resolved Förster resonance energy transfer (trFRET), we study the intra-molecular structural heterogeneity of the neurofilament low intrinsically disordered tail domain (NFLt). Using theoretical results of polymer physics, we find that the Flory scaling exponent of NFLt sub-segments correlates linearly with their net charge, ranging from statistics of ideal to self-avoiding chains. Surprisingly, measuring the same segments in the context of the whole NFLt protein, we find that regardless of the peptide sequence, the segments' structural statistics are more expanded than when measured independently. Our findings show that while polymer physics can, to some level, relate the IDP's sequence to its ensemble conformations, long-range contacts between distant amino acids play a crucial role in determining intra-molecular structures. This emphasizes the necessity of advanced polymer theories to fully describe IDPs ensembles with the hope it will allow us to model their biological function.
Can neural quantum states learn volume-law ground states?
Creators: name: Passetti, Giacomo
name: Hofmann, Damian
name: Neitemeier, Pit
name: Grunwald, Lukas
name: Sentef, Michael A.
name: Kennes, Dante M.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We study whether neural quantum states based on multi-layer feed-forward networks can find ground states which exhibit volume-law entanglement entropy. As a testbed, we employ the paradigmatic Sachdev-Ye-Kitaev model. We find that both shallow and deep feed-forward networks require an exponential number of parameters in order to represent the ground state of this model. This demonstrates that sufficiently complicated quantum states, although being physical solutions to relevant models and not pathological cases, can still be difficult to learn to the point of intractability at larger system sizes. This highlights the importance of further investigations into the physical properties of quantum states amenable to an efficient neural representation.
Trace-Class and Nuclear Operators
Creators: name: Kubrusly, Carlos S.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Functional Analysis (math.FA)
subject: FOS: Mathematics
subject: 47B10, 47A80, 46M05

description: This paper explores the long journey from projective tensor products of a pair of Banach spaces, passing through the definition of nuclear operators still on the realm of projective tensor products, to the of notion of trace-class operators on a Hilbert space, and shows how and why these concepts (nuclear and trace-class operators, that is) agree in the end.
Gaussian work extraction from random Gaussian states is nearly impossible
Creators: name: Singh, Uttam
name: Korbicz, Jarosław K.
name: Cerf, Nicolas J.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: Quantum thermodynamics can be naturally phrased as a theory of quantum state transformation and energy exchange for small-scale quantum systems undergoing thermodynamical processes, thereby making the resource theoretical approach very well suited. A key resource in thermodynamics is the extractable work, forming the backbone of thermal engines. Therefore it is of interest to characterize quantum states based on their ability to serve as a source of work. From a near-term perspective, quantum optical setups turn out to be ideal test beds for quantum thermodynamics; so it is important to assess work extraction from quantum optical states. Here, we show that Gaussian states are typically useless for Gaussian work extraction. More specifically, by exploiting the ``concentration of measure'' phenomenon, we prove that the probability that the Gaussian extractable work from a zero-mean energy-bounded multimode random Gaussian state is nonzero is exponentially small. This result can be thought of as an $ε$-no-go theorem for work extraction from Gaussian states under Gaussian unitaries, thereby revealing a fundamental limitation on the quantum thermodynamical usefulness of Gaussian components.
description: 7+8 pages, 2 figures, close to the published version
Testing alternative theories of gravity with space-based gravitational wave detectors
Creators: name: Gao, Qing
name: You, Yujie
name: Gong, Yungui
name: Zhang, Chao
name: Zhang, Chunyu
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We use gravitational waves (GWs) from binary black holes (BBHs) and neutron stars inspiraling into intermediate-mass black holes to evaluate how accurately the future space-based GW detectors such as LISA, Taiji and TianQin and their combined networks can determine source parameters and constrain alternative theories of gravity. We find that, compared with single detector, the detector network can greatly improve the estimation errors of source parameters, especially the sky localization, but the improvement of the constraint on the graviton mass $m_g$ and the Brans-Dicke coupling constant $ω_{BD}$ is small. We also consider possible scalar modes existed in alternative theories of gravity and we find the inclusion of the scalar mode has little effect on the constraints on source parameters, $m_g$, and $ω_{BD}$ and the parametrized amplitude $A_B$ of scalar modes are small. For the constraint on the graviton mass, we consider both the effects in the GW phase and the transfer function due to the mass of graviton. With the network of LISA, Taiji and TianQin, we get the lower bound on the graviton Compton wavelength $λ_g\gtrsim 1.24 \times 10^{20}$ m for BBHs with masses $(10^6+10^7)M_\odot$, and $A_B< 5.7\times 10^{-4}$ for BBHs with masses $(1+2)\times 10^5M_\odot$; $ω_{BD}>6.11\times10^{6}$ for neutron star-black hole binary with masses $(1.4+400)M_{\odot}$.
description: 21 pages, 3 figures, 4 tables. Typos corrected and references updated. Published in PRD
Symmetry preserving truncations of the gap and Bethe-Salpeter equations
Creators: name: Binosi, Daniele
name: Chang, Lei
name: Papavassiliou, Joannis
name: Qin, Si-Xue
name: Roberts, Craig D.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Nuclear Theory (nucl-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Ward-Green-Takahashi (WGT) identities play a crucial role in hadron physics, e.g. imposing stringent relationships between the kernels of the one- and two-body problems, which must be preserved in any veracious treatment of mesons as bound-states. In this connection, one may view the dressed gluon-quark vertex, $Γ_μ^a$, as fundamental. We use a novel representation of $Γ_μ^a$, in terms of the gluon-quark scattering matrix, to develop a method capable of elucidating the unique quark-antiquark Bethe-Salpeter kernel, $K$, that is symmetry-consistent with a given quark gap equation. A strength of the scheme is its ability to expose and capitalise on graphic symmetries within the kernels. This is displayed in an analysis that reveals the origin of $H$-diagrams in $K$, which are two-particle-irreducible contributions, generated as two-loop diagrams involving the three-gluon vertex, that cannot be absorbed as a dressing of $Γ_μ^a$ in a Bethe-Salpeter kernel nor expressed as a member of the class of crossed-box diagrams. Thus, there are no general circumstances under which the WGT identities essential for a valid description of mesons can be preserved by a Bethe-Salpeter kernel obtained simply by dressing both gluon-quark vertices in a ladder-like truncation; and, moreover, adding any number of similarly-dressed crossed-box diagrams cannot improve the situation.
description: 6 pages, 8 figures
Graph test of controllability in qubit arrays: A systematic way to determine the minimum number of external controls
Creators: name: Gago-Encinas, Fernando
name: Leibscher, Monika
name: Koch, Christiane P.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The ability to implement any desired quantum logic gate on a quantum processing unit is equivalent to evolution-operator controllability of the qubits. Conversely, controllability analysis can be used to minimize the resources, i.e., the number of external controls and qubit-qubit couplings, required for universal quantum computing. Standard controllability analysis, consisting in the construction of the dynamical Lie algebra, is, however, impractical already for a comparatively small number of qubits. Here, we show how to leverage an alternative approach, based on a graph representation of the Hamiltonian, to determine controllability of arrays of coupled qubits. We provide a complete computational framework and exemplify it for arrays of five qubits, inspired by the ibmq_quito architecture. We find that the number of controls can be reduced from five to one for complex qubit-qubit couplings and to two for standard qubit-qubit couplings.
description: 18 pages, 7 figures, 3 tables, 3 algorithms
Exact WKB Analysis of N = 2 Gauge Theories
Creators: name: Ashok, Sujay K.
name: Jatkar, Dileep P.
name: John, Renjan R.
name: Raman, Madhusudhan
name: Troost, Jan
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study N = 2 supersymmetric gauge theories with gauge group SU(2) coupled to fundamental flavours, covering all asymptotically free and conformal cases. We re-derive, from the conformal field theory perspective, the differential equations satisfied by omega deformed instanton partition functions. We confirm their validity at leading order in one of the deformation parameters via a saddle-point analysis of the partition function. In the semi-classical limit we show that these differential equations take a form amenable to exact WKB analysis. We compute the monodromy group associated to the differential equations in terms of deformed and Borel resummed Seiberg-Witten data. For each case, we study pairs of Stokes graphs that are related by flips and pops, and show that the monodromy groups allow one to confirm the Stokes automorphisms that arise as the phase of the deformation parameter is varied. Finally, we relate the Borel resummed monodromies with the traditional Seiberg-Witten variables in the semi-classical limit.
description: 53 pages, 19 figures
Modelling the variable broad-band optical/UV/X-ray spectrum of PG1211+143: Implications for the ionized outflow
Creators: name: Papadakis, I. E.
name: Nicastro, F.
name: Panagiotou, C.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We present the results from a detailed analysis of the 2007 Swift monitoring campaign of the quasar PG1211+143. We constructed broad-band, optical/UV/X-ray spectral energy distributions over three X-ray flux intervals. We fitted them with a model which accounts for the disc and the X-ray coronal emission and the warm absorber (well established in this source). The three flux spectra are well fitted by the model we considered. The disc inner temperature remains constant at ~2 eV, while X-rays are variable both in spectral slope and normalization. The absorber covers almost 90% of the central source. It is outflowing with a velocity less than 2.3*10^4 km/s (3sigma upper limit), and has a column density of ~10^23.2. Its ionization parameter varies by a factor of 1.6, and it is in photo-ionizing equilibrium with the ionizing flux. It is located at a distance of less than 0.35 pc from the central source and its relative thickness, DR/R is less than 0.1. The absorber' s ionization parameter variations can explain the larger than average amplitude of the X-ray variations. The absence of optical/UV variations (consistent with the high black hole mass estimate) argues against the presence of inward propagating disc fluctuations and strong X-ray illumination of the disc (in agreement with the low ratio of X-ray over the bolometric luminosity of ~20-35). We estimate an upper limit for the mass outflow of ~5 solar masses per year (~2.3 times the Eddington mass accretion rate). If the outflow rate is indeed that high, then it must be a short-lived episode in the quasar's life time. Finally, we estimate an upper limit for the kinetic power of the outflow of ~1.4*10^43 ergs/s. This outflow cannot deploy significant mechanical energy to the surrounding ISM of the quasar's host galaxy, but is sufficient to heat the ISM to 10^7 K and to produce a fast decline to the star formation rate of the galaxy.
description: Accepted for publication by A&A
Parallax Results From URAT Epoch Data
Creators: name: Finch, Charlie
name: Zacharias, Norbert
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We present 1103 trigonometric parallaxes and proper motions from the United States Naval Observatory (USNO) Robotic Astrometric Telescope (URAT) observations taken at the Naval Observatory Flagstaff Station (NOFS) over a 3 year period from April 2012 to June 2015 covering the entire sky north of about minus 10 deg declination. We selected 2 samples previously suspected nearby stars from known photometric distances and stars showing a large, significant parallax signature in URAT epoch data without any prior selection criteria. All systems presented in this paper have an observed parallax greater than equal to 40 mas with no previous published trigonometric parallax. The formal errors on these weighted parallax solutions are mostly between 4 and 10 mas. This sample gives a significant (order 50%) increase to the number of known systems having a trigonometric parallax to be within 25 pc of the Sun (without applying Lutz Kelker bias corrections). A few of these are found to be within 10 pc. Many of these new nearby stars display a total proper motion of less than 200 mas per year. URAT parallax results have been verified against Hipparcos and Yale data for stars in common. The publication of all significant parallax observations from URAT data is in preparation for CDS.
description: 47 pages includes: 4 tables,18 figures, Accepted for publication in The Astronomical Journal
The Advanced LIGO Input Optics
Creators: name: Mueller, Chris
name: Arain, Muzammil
name: Ciani, Giacomo
name: DeRosa, Ryan
name: Effler, Anamaria
name: Feldbaum, David
name: Frolov, Valery
name: Fulda, Paul
name: Gleason, Joseph
name: Heintze, Matthew
name: King, Eleanor
name: Kokeyama, Keiko
name: Korth, William
name: Martin, Rodica
name: Mullavey, Adam
name: Poeld, Jan
name: Quetschke, Volker
name: Reitze, David
name: Tanner, David
name: Williams, Luke
name: Mueller, Guido
Publisher: name: arXiv
Year: 2016
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: The Advanced LIGO gravitational wave detectors are nearing their design sensitivity and should begin taking meaningful astrophysical data in the fall of 2015. These resonant optical interferometers will have unprecedented sensitivity to the strains caused by passing gravitational waves. The input optics play a significant part in allowing these devices to reach such sensitivities. Residing between the pre-stabilized laser and the main interferometer, the input optics is tasked with preparing the laser beam for interferometry at the sub-attometer level while operating at continuous wave input power levels ranging from 100 mW to 150 W. These extreme operating conditions required every major component to be custom designed. These designs draw heavily on the experience and understanding gained during the operation of Initial LIGO and Enhanced LIGO. In this article we report on how the components of the input optics were designed to meet their stringent requirements and present measurements showing how well they have lived up to their design.
Finding defects in glasses through machine learning
Creators: name: Ciarella, Simone
name: Khomenko, Dmytro
name: Berthier, Ludovic
name: Mocanu, Felix C.
name: Reichman, David R.
name: Scalliet, Camille
name: Zamponi, Francesco
Publisher: name: arXiv
Year: 2022
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: Structural defects control the kinetic, thermodynamic and mechanical properties of glasses. For instance, rare quantum tunneling two-level systems (TLS) govern the physics of glasses at very low temperature. Because of their extremely low density, it is very hard to directly identify them in computer simulations. We introduce a machine learning approach to efficiently explore the potential energy landscape of glass models and identify desired classes of defects. We focus in particular on TLS and we design an algorithm that is able to rapidly predict the quantum splitting between any two amorphous configurations produced by classical simulations. This in turn allows us to shift the computational effort towards the collection and identification of a larger number of TLS, rather than the useless characterization of non-tunneling defects which are much more abundant. Finally, we interpret our machine learning model to understand how TLS are identified and characterized, thus giving direct physical insight into their microscopic nature.
Hard X-ray helical dichroism of disordered molecular media
Creators: name: Rouxel, Jeremy R.
name: Rosner, Benedikt
name: Karpov, Dmitry
name: Bacellar, Camila
name: Mancini, Giulia F.
name: Zinna, Francesco
name: Kinschel, Dominik
name: Cannelli, Oliviero
name: Oppermann, Malte
name: Svetina, Cris
name: Diaz, Ana
name: Lacour, Jerome
name: David, Christian
name: Chergui, Majed
Publisher: name: arXiv
Year: 2022
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Chirality is a structural property of molecules lacking mirror symmetry that has strong implications in diverse fields, ranging from life to materials sciences. Established spectroscopic methods that are sensitive to chirality, such as circular dichroism (CD), exhibit weak signal contributions on an achiral background. Helical dichroism (HD), which is based on the orbital angular momentum (OAM) of light, offers a new approach to probe molecular chirality, but it has never been demonstrated on disordered samples. Furthermore, in the optical domain the challenge lies in the need to transfer the OAM of the photon to an electron that is localized on an Å-size orbital. Here, we overcome this challenge using hard X-rays with spiral Fresnel zone, which can induce an OAM. We present the first HD spectra of a disordered powder sample of enantiopure molecular complexes of [Fe(4,4'-diMebpy)3]2+ at the iron K-edge (7.1 keV) with OAM-carrying beams. The HD spectra exhibit the expected inversions of signs switching from a left to a right helical wave front or from an enantiomer to the other. The asymmetry ratios for the HD spectra are within one to five percent for OAM beams with topological charges of one and three. These results open a new window into the studies of molecular chirality and its interaction with the orbital angular momentum of light.
description: 15 pages, 5 figures