cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Testing eccentric corrections to the radiation-reaction force in the test-mass limit of effective-one-body models
Creators: name: Faggioli, Guglielmo
name: van de Meent, Maarten
name: Buonanno, Alessandra
name: Gamboa, Aldo
name: Khalil, Mohammed
name: Khanna, Gaurav
Publisher: name: arXiv
Year: 2024
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: In this work, we test an effective-one-body radiation-reaction force for eccentric planar orbits of a test mass in a Kerr background, which contains third-order post-Newtonian (PN) non-spinning and second-order PN spin contributions. We compare the analytical fluxes connected to two different resummations of this force, truncated at different PN orders in the eccentric sector, with the numerical fluxes computed through the use of frequency- and time-domain Teukolsky-equation codes. We find that the different PN truncations of the radiation-reaction force show the expected scaling in the weak gravitational-field regime, and we observe a fractional difference with the numerical fluxes that is $<5 \%$, for orbits characterized by eccentricity $0 \le e \le 0.7$, central black-hole spin $-0.99 M \le a \le 0.99 M$ and fixed orbital-averaged quantity $x=\langle MΩ\rangle^{2/3} = 0.06$, corresponding to the mildly strong-field regime with semilatera recta $9 M
description: 27 pages, 7 figures
On blow-up for the supercritical defocusing nonlinear wave equation
Creators: name: Shao, Feng
name: Wei, Dongyi
name: Zhang, Zhifei
Publisher: name: arXiv
Year: 2024
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: In this paper, we consider the defocusing nonlinear wave equation $-\partial_t^2u+Δu=|u|^{p-1}u$ in $\mathbb R\times \mathbb R^d$. Building on our companion work ({\it \small Self-similar imploding solutions of the relativistic Euler equations}), we prove that for $d=4, p\geq 29$ and $d\geq 5, p\geq 17$, there exists a smooth complex-valued solution that blows up in finite time.
description: 56 pages
Invariant measures for monotone SPDE's with multiplicative noise term
Creators: name: Es-Sarhir, A.
name: Scheutzow, M.
name: Tölle, J. M.
name: van Gaans, O.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 35R60, 60H15, 60H20, 47D07

description: We study diffusion processes corresponding to infinite dimensional semilinear stochastic differential equations with local Lipschitz drift term and an arbitrary Lipschitz diffusion coefficient. We prove tightness and the Feller property of the solution to show existence of an invariant measure. As an application we discuss stochastic reaction diffusion equations.
description: 10 pages
ALMA observations of the Extended Green Object G19.01$-$0.03: I. A Keplerian disc in a massive protostellar system
Creators: name: Williams, Gwenllian M.
name: Cyganowski, Claudia J.
name: Brogan, Crystal L.
name: Hunter, Todd R.
name: Ilee, John D.
name: Nazari, Pooneh
name: Kruijssen, J. M. Diederik
name: Smith, Rowan J.
name: Bonnell, Ian A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Using the Atacama Large Millimetre/submillimeter Array (ALMA) and the Karl G. Jansky Very Large Array (VLA), we observed the Extended Green Object (EGO) G19.01$-$0.03 with sub-arcsecond resolution from 1.05 mm to 5.01 cm wavelengths. Our $\sim0.4''\sim1600$ AU angular resolution ALMA observations reveal a velocity gradient across the millimetre core MM1, oriented perpendicular to the previously known bipolar molecular outflow, that is consistently traced by 20 lines of 8 molecular species with a range of excitation temperatures, including complex organic molecules (COMs). Kinematic modelling shows the data are well described by models that include a disc in Keplerian rotation and infall, with an enclosed mass of $40-70 \mathrm{M}_{\odot}$ (within a 2000 AU outer radius) for a disc inclination angle of $i=40^{\circ}$, of which $5.4-7.2 \mathrm{M}_{\odot}$ is attributed to the disc. Our new VLA observations show that the 6.7 GHz Class II methanol masers associated with MM1 form a partial ellipse, consistent with an inclined ring, with a velocity gradient consistent with that of the thermal gas. The disc-to-star mass ratio suggests the disc is likely to be unstable and may be fragmenting into as-yet-undetected low mass stellar companions. Modelling the centimetre--millimetre spectral energy distribution of MM1 shows the ALMA 1.05 mm continuum emission is dominated by dust, whilst a free-free component, interpreted as a hypercompact HII region, is required to explain the VLA $\sim$5 cm emission. The high enclosed mass derived for a source with a moderate bolometric luminosity ($\sim$10$^{4} \mathrm{L}_{\odot}$) suggests that the MM1 disc may feed an unresolved high-mass binary system.
description: 15 pages, 8 figures, 5 tables, Accepted for publication in MNRAS
Mastering truss structure optimization with tree search
Creators: name: Garayalde, Gabriel
name: Rosafalco, Luca
name: Torzoni, Matteo
name: Corigliano, Alberto
Publisher: name: arXiv
Year: 2024
Subjects: subject: Computational Engineering, Finance, and Science (cs.CE)
subject: FOS: Computer and information sciences

description: This study investigates the combined use of generative grammar rules and Monte Carlo Tree Search (MCTS) for optimizing truss structures. Our approach accommodates intermediate construction stages characteristic of progressive construction settings. We demonstrate the significant robustness and computational efficiency of our approach compared to alternative reinforcement learning frameworks from previous research activities, such as Q-learning or deep Q-learning. These advantages stem from the ability of MCTS to strategically navigate large state spaces, leveraging the upper confidence bound for trees formula to effectively balance exploitation-exploration trade-offs. We also emphasize the importance of early decision nodes in the search tree, reflecting design choices crucial for highly performative solutions. Additionally, we show how MCTS dynamically adapts to complex and extensive state spaces without significantly affecting solution quality. While the focus of this paper is on truss optimization, our findings suggest MCTS as a powerful tool for addressing other increasingly complex engineering applications.
Third-Order Density Perturbation and One-Loop Power Spectrum in Dark-Energy-Dominated Universe
Creators: name: Takahashi, Ryuichi
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We investigate the third-order density perturbation and the one-loop correction to the linear power spectrum in the dark-energy cosmological model. Our main interest is to understand the dark-energy effect on baryon acoustic oscillations in a quasi-nonlinear regime ($k \approx 0.1h$/Mpc). Analytical solutions and simple fitting formulae are presented for the dark-energy model with the general time-varying equation of state $w(a)$. It turns out that the power spectrum coincides with the approximate result based on the EdS (Einstein de-Sitter) model within 1% for $k<0.4h/$Mpc at $z=0$ in the WMAP (Wilkinson Microwave Anisotropy Probe) 5yr best-fitting cosmological model, which suggests that the cosmological dependence is very small.
description: 11 pages, Prog. Ther. Phys. in press, minor changes, references added
Betti numbers of Stanley-Reisner rings determine hierarchical Markov degrees
Creators: name: Petrović, Sonja
name: Stokes, Erik
Publisher: name: arXiv
Year: 2009
Subjects: subject: Commutative Algebra (math.AC)
subject: Combinatorics (math.CO)
subject: Statistics Theory (math.ST)
subject: FOS: Mathematics

description: There are two seemingly unrelated ideals associated with a simplicial complex Δ. One is the Stanley-Reisner ideal I_Δ, the monomial ideal generated by minimal non-faces of Δ, well-known in combinatorial commutative algebra. The other is the toric ideal I_{M(Δ)} of the facet subring of Δ, whose generators give a Markov basis for the hierarchical model defined by Δ, playing a prominent role in algebraic statistics. In this note we show that the complexity of the generators of I_{M(Δ)} is determined by the Betti numbers of I_Δ. The unexpected connection between the syzygies of the Stanley-Reisner ideal and degrees of minimal generators of the toric ideal provide a framework for further exploration of the connection between the model and its many relatives in algebra and combinatorics.
description: Section 6 outlines few open problems. (Final version, differs slightly then publication.) Version3 was a major revision: proved Conjecture from previous version for all simplicial complexes
Metastable Quasimolecules in Excited Gases
Creators: name: Malnev, V. N.
name: Naryshkin, R. A.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Quasimolecules, which consist of two differently excited atoms in a resonantly excited gas, are considered. The energy of dissociation and typical sizes of such molecules are calculated in the first order of quantum-mechanical perturbation theory with the help of the dipole-dipole interaction operator. It is shown that there exist metastable quasimolecules, whose dipole radiative transition to the ground state (two non-excited atoms) is forbidden. The lifetime of such molecules is estimated and it is shown that quasimolecules may considerably affect the transport processes in a resonantly excited gas.
description: 6 pages, no figures, 1 table
Additional file 1 of Associations between grip strength, brain structure, and mental health in > 40,000 participants from the UK Biobank
Creators: name: Jiang, Rongtao
name: Westwater, Margaret L.
name: Noble, Stephanie
name: Rosenblatt, Matthew
name: Dai, Wei
name: Qi, Shile
name: Sui, Jing
name: Calhoun, Vince D.
name: Scheinost, Dustin
Publisher: name: figshare
Year: 2022
Subjects: subject: Medicine
subject: Neuroscience
subject: Physiology
subject: FOS: Biological sciences
subject: Biological Sciences not elsewhere classified
subject: Mental Health

description: Additional file 1: Table S1. Neurological conditions/incidents that are used to exclude participants in UK Biobank. Table S2. UK Biobank cognition and mental health measures used in the current study. Table S3. Association between grip strength and behavioral phenotypes. Table S4. Brain regions showing significant correlations with grip strength. Table S5. Brain regions showing significant correlations with grip strength after controlling for the total intracranial volume. Table S6. Results of the mediation analyses between grip strength, phenotypes, and mean grey matter volume. Fig. S1. A brief summary of the population characteristics of all participants used in the current study. Fig. S2. The 139 brain regions and their names. Fig. S3. The top four behavioral outcomes showing the strongest associations with grip strength. Fig. S4. Results of the classic two-wave cross-lagged panel model for 15 behavioral phenotypes that have complete data at two time points. Fig. S5. The correlation of association maps (T-maps) between the cases with and without including the total intracranial volume (ICV) and the squared ICV as covariates in examining the association of grip strength with regional grey matter volume across 139 regions. Fig. S6. Regional distribution of associations between grey matter volume and grip strength and the mediation effect of mean GMV in females. Fig. S7. Regional distribution of associations between grey matter volume and grip strength and the mediation effect of mean GMV in males. Fig. S8. The correlation of T-maps between the cases with and without including the total intracranial volume as a covariate in examining the association of grey matter volumes with behavioral outcomes across 139 regions. Fig. S9. Regional distribution of associations between grey matter volume and four representative behavioral phenotypes. Fig. S10. Mediation effects of the first principal component of 139 regional GMV on the association between grip strength and behavioral outcomes.
Electro-osmotic diode based on colloidal nano-valves between double membranes
Creators: name: Koyama, Shihori
name: Inoue, Daisuke
name: Okada, Akihisa
name: Yoshida, Hiroaki
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: The rectification of electro-osmotic flows is important in micro/nano fluidics applications such as micro-pumps and energy conversion devices. Here, we propose a simple electro-osmotic diode in which colloidal particles are contained between two parallel membranes with different pore densities. While the flow in the forward direction just pushes the colloidal particles toward the high-pore-density membrane, the backward flow is blocked by the particles near the low-pore-density membrane, which clog the pores. Nonequilibrium molecular dynamics simulations show a strong nonlinear dependence on the electric field for both the electric current and electro-osmotic flow, indicating diode characteristics. A mathematical model to reproduce the electro-osmotic diode behavior is constructed, introducing an effective pore diameter as a model for pores clogged by the colloidal particles. Good agreement is obtained between the proposed model with estimated parameter values and the results of direct molecular dynamics simulations. The proposed electro-osmotic diode has potential application in downsized microfluidic pumps, e.g., the pump induced under AC electric fields.
description: Accepted for publication in Physical Review Research
Equal-time two-point correlation functions in Coulomb gauge Yang-Mills theory
Creators: name: Campagnari, D.
name: Weber, A.
name: Reinhardt, H.
name: Astorga, F.
name: Schleifenbaum, W.
Publisher: name: arXiv
Year: 2009
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We apply a functional perturbative approach to the calculation of the equal-time two-point correlation functions and the potential between static color charges to one-loop order in Coulomb gauge Yang-Mills theory. The functional approach proceeds through a solution of the Schroedinger equation for the vacuum wave functional to order g^2 and derives the equal-time correlation functions from a functional integral representation via new diagrammatic rules. We show that the results coincide with those obtained from the usual Lagrangian functional integral approach, extract the beta function, and determine the anomalous dimensions of the equal-time gluon and ghost two-point functions and the static potential under the assumption of multiplicative renormalizability to all orders.
description: 33 pages, 7 figures with Feyman diagrams generated with pstricks; revised version with additional references and comments on possible applications added in the conclusions; accepted for publication in Nucl. Phys. B
Hot neutron matter from a Self-Consistent Green's Functions approach
Creators: name: Rios, A.
name: Polls, A.
name: Vidaña, I.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: A systematic study of the microscopic and thermodynamical properties of pure neutron matter at finite temperature within the Self-Consistent Green's Function approach is performed. The model dependence of these results is analyzed by both comparing the results obtained with two different microscopic interactions, the CD-BONN and the Argonne V18 potentials, and by analyzing the results obtained with other approaches, such as the Brueckner--Hartree--Fock approximation, the variational approach and the virial expansion.
description: 34 pages, 10 figures
Entanglement of the Antisymmetric State
Creators: name: Christandl, Matthias
name: Schuch, Norbert
name: Winter, Andreas
Publisher: name: arXiv
Year: 2009
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We analyse the entanglement of the antisymmetric state in dimension d x d and present two main results. First, we show that the amount of secrecy that can be extracted from the state is low, more precisely, the distillable key is bounded by O(1/d). Second, we show that the state is highly entangled in the sense that a large number of ebits are needed in order to create the state: entanglement cost is larger than a constant, independent of d. The second result is shown to imply that the regularised relative entropy with respect to separable states is also lower bounded by a constant. Finally, we note that the regularised relative entropy of entanglement is asymptotically continuous in the state. Elementary and advanced facts from the representation theory of the unitary group, including the concept of plethysm, play a central role in the proofs of the main results.
description: 19 pages, 2 plethysms, not a single figure; requires young.sty and youngtab.sty; v2 has some small errors corrected and contains a new result regarding relative entropy of entanglement; v3 has a new title, v4 published version
Current noise of a superconducting single electron transistor coupled to a resonator
Creators: name: Harvey, T. J.
name: Rodrigues, D. A.
name: Armour, A. D.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Superconductivity (cond-mat.supr-con)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We analyze the current and zero-frequency current noise properties of a superconducting single electron resonator (SSET) coupled to a resonator, focusing on the regime where the SSET is operated in the vicinity of the Josephson quasiparticle resonance. We consider a range of coupling strengths and resonator frequencies to reflect the fact that in practice the system can be tuned to quite a high degree with the resonator formed either by a nanomechanical oscillator or a superconducting stripline fabricated in close proximity to the SSET. For very weak couplings the SSET acts on the resonator like an effective thermal bath. In this regime the current characteristics of the SSET are only weakly modified by the resonator. Using a mean field approach, we show that the current noise is nevertheless very sensitive to the correlations between the resonator and the SSET charge. For stronger couplings, the SSET can drive the resonator into limit cycle states where self-sustained oscillation occurs and we find that regions of well-defined bistability exist. Dynamical transitions into and out of the limit cycle state are marked by strong fluctuations in the resonator energy, but these fluctuations are suppressed within the limit cycle state. We find that the current noise of the SSET is strongly influenced by the fluctuations in the resonator energy and hence should provide a useful indicator of the resonator's dynamics.
description: Reduced quality figures for arXiv version; v2 minor corrections
Neural Quantum State Study of Fracton Models
Creators: name: Machaczek, Marc
name: Pollet, Lode
name: Liu, Ke
Publisher: name: arXiv
Year: 2024
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: Fracton models host unconventional topological orders in three and higher dimensions and provide promising candidates for quantum memory platforms. Understanding their robustness against quantum fluctuations is an important task but also poses great challenges due to the lack of efficient numerical tools. In this work, we establish neural quantum states (NQS) as new tools to study phase transitions in these models. Exact and efficient parametrizations are derived for three prototypical fracton codes -- the checkerboard and X-cube model, as well as Haah's code -- both in terms of a restricted Boltzmann machine (RBM) and a correlation-enhanced RBM. We then adapt the correlation-enhanced RBM architecture to a perturbed checkerboard model and reveal its strong first-order phase transition between the fracton phase and a trivial field-polarizing phase. To this end, we simulate this highly entangled system on lattices of up to 512 qubits with high accuracy, representing a cutting-edge application of variational neural-network methods. In addition, we reproduce the phase transition of the X-cube model previously obtained with quantum Monte Carlo and high-order series expansion methods. Our work demonstrates the remarkable potential of NQS in studying complicated three-dimensional problems and highlights physics-oriented constructions of NQS architectures.
description: 39 pages, 21 figures, (Re-)Submission to SciPost Added X-cube simulations, extended Figure 9 (and additional Figure 20), added references
Bose-Einstein condensation in an optical lattice: A perturbation approach
Creators: name: Trallero-Giner, C.
name: Lopez-Richard, V.
name: Chung, Ming-Chiang
name: Buchleitner, Andreas
Publisher: name: arXiv
Year: 2008
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: We derive closed analytical expressions for the order parameter $Φ(x)$ and for the chemical potential $μ$ of a Bose-Einstein Condensate loaded into a harmonically confined, one dimensional optical lattice, for sufficiently weak, repulsive or attractive interaction, and not too strong laser intensities. Our results are compared with exact numerical calculations in order to map out the range of validity of the perturbative analytical approach. We identify parameter values where the optical lattice compensates the interaction-induced nonlinearity, such that the condensate ground state coincides with a simple, single particle harmonic oscillator wave function.
New Insight into the Formation Mechanism of the Energetic Particle Reservoirs in the Heliosphere
Creators: name: He, H. -Q.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Space Physics (physics.space-ph)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: The concept of energetic particle reservoirs, essentially based on the assumption of the presence of outer reflecting boundaries/magnetic mirrors or diffusion barriers (deterministic) rather than on the effect of particle diffusive propagation (stochastic) in magnetic turbulence, has been used for decades to describe the space-extended decay phases of energetic particle events within the fields of space physics, solar physics, and plasma physics. Using five-dimensional time-dependent Fokker-Planck transport equation simulations, in this work we demonstrate that the so-called particle reservoirs are naturally explained and quantitatively reproduced by diffusion processes in turbulent magnetic fields, without invoking the hypothesis of reflecting boundaries. Our results strongly suggest that the so-called "reservoir" (based on deterministic structure) should be renamed "flood" (based on stochastic diffusion), which symbolizes an authentic shift in thinking and in pragmatic rationale for the studies of energetic particles and relevant plasma phenomena in heliophysics and in astrophysics.
description: Something in textbooks/books has been changed, forever
The Alexander-Orbach conjecture holds in high dimensions
Creators: name: Kozma, Gady
name: Nachmias, Asaf
Publisher: name: arXiv
Year: 2008
Subjects: subject: Probability (math.PR)
subject: Mathematical Physics (math-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: We examine the incipient infinite cluster (IIC) of critical percolation in regimes where mean-field behavior has been established, namely when the dimension d is large enough or when d>6 and the lattice is sufficiently spread out. We find that random walk on the IIC exhibits anomalous diffusion with the spectral dimension d_s=4/3, that is, p_t(x,x)= t^{-2/3+o(1)}. This establishes a conjecture of Alexander and Orbach. En route we calculate the one-arm exponent with respect to the intrinsic distance.
description: 25 pages, 2 figures. To appear in Inventiones Mathematicae
Scalable Training of Trustworthy and Energy-Efficient Predictive Graph Foundation Models for Atomistic Materials Modeling: A Case Study with HydraGNN
Creators: name: Pasini, Massimiliano Lupo
name: Choi, Jong Youl
name: Mehta, Kshitij
name: Zhang, Pei
name: Rogers, David
name: Bae, Jonghyun
name: Ibrahim, Khaled Z.
name: Aji, Ashwin M.
name: Schulz, Karl W.
name: Polo, Jorda
name: Balaprakash, Prasanna
Publisher: name: arXiv
Year: 2024
Subjects: subject: Machine Learning (cs.LG)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences
subject: C.2.4; I.2.11
subject: 68T07, 68T09

description: We present our work on developing and training scalable, trustworthy, and energy-efficient predictive graph foundation models (GFMs) using HydraGNN, a multi-headed graph convolutional neural network architecture. HydraGNN expands the boundaries of graph neural network (GNN) computations in both training scale and data diversity. It abstracts over message passing algorithms, allowing both reproduction of and comparison across algorithmic innovations that define nearest-neighbor convolution in GNNs. This work discusses a series of optimizations that have allowed scaling up the GFMs training to tens of thousands of GPUs on datasets consisting of hundreds of millions of graphs. Our GFMs use multi-task learning (MTL) to simultaneously learn graph-level and node-level properties of atomistic structures, such as energy and atomic forces. Using over 154 million atomistic structures for training, we illustrate the performance of our approach along with the lessons learned on two state-of-the-art United States Department of Energy (US-DOE) supercomputers, namely the Perlmutter petascale system at the National Energy Research Scientific Computing Center and the Frontier exascale system at Oak Ridge Leadership Computing Facility. The HydraGNN architecture enables the GFM to achieve near-linear strong scaling performance using more than 2,000 GPUs on Perlmutter and 16,000 GPUs on Frontier.
description: 51 pages, 32 figures
Multi-Meta-RAG: Improving RAG for Multi-Hop Queries using Database Filtering with LLM-Extracted Metadata
Creators: name: Poliakov, Mykhailo
name: Shvai, Nadiya
Publisher: name: arXiv
Year: 2024
Subjects: subject: Computation and Language (cs.CL)
subject: Artificial Intelligence (cs.AI)
subject: Databases (cs.DB)
subject: FOS: Computer and information sciences

description: The retrieval-augmented generation (RAG) enables retrieval of relevant information from an external knowledge source and allows large language models (LLMs) to answer queries over previously unseen document collections. However, it was demonstrated that traditional RAG applications perform poorly in answering multi-hop questions, which require retrieving and reasoning over multiple elements of supporting evidence. We introduce a new method called Multi-Meta-RAG, which uses database filtering with LLM-extracted metadata to improve the RAG selection of the relevant documents from various sources, relevant to the question. While database filtering is specific to a set of questions from a particular domain and format, we found out that Multi-Meta-RAG greatly improves the results on the MultiHop-RAG benchmark. The code is available at https://github.com/mxpoliakov/Multi-Meta-RAG.
description: Accepted to ICTERI 2024 Posters Track
The digestive tract of a harpacticoid copepod, Tiqriopus californicu: a light and electron microscope study
Creators: name: Sullivan, Druscilla Shirley
Publisher: name: University of British Columbia
Year: 2010

description: A study on the digestive tract of a harpacticoid copepod, 2i3lio£Ss californicus, was carried out using techniques of light and electron microscopy. It was found that a curved, cuticulized esophagus extends from the ventral mouth to the midgut. Its musculature and shape allows fairly large food particles to enter the gut. The noncuticulized portion of the digestive tract consists of; 1. A single, anterior, spherical midgut caecum, 2. An anterior midgut extending from the midgut caecum to the joint at the beginning of the urosome, 3. A posterior midgut extending almost the length of the urosome. The cuticulized hindgut can be divided, structurally, into anterior and posterior regions. It is suggested that the anterior hindgut functions in ion and water regulation as well as begins the formation of a faecal pellet. The posterior hindgut compacts the faecal pellet and retains it until defaecation. At the light and electron microscope levels four cell types could be distinguished. By studying the cell's position in the gut, electron density, amount of lipid, amount and type of vesiculation and the abundance and position of the cell*s organelles, functions for these cells were determined: 1. cell type one is an embryonic cell which will replace cells worn away or lost in secretion. 2. Cell type two functions mainly in the synthesis and secretion of proteins and also plays a role in lipid absorption. 3. Cell type three appears to function mainly in lipid absorption. 4. Cell type four also functions in lipid absorption but this cell is only found in the anterior midgut and the type of vesicles found in this cell suggest a different type of absorption is occurring than in cell type three. From the abundance of each cell type, the length of the microvilli, the development of the basal lamina and luminal projections, the following conclusions were made: 1. The midgut caecum functions mainly for absorption of digested nutrients. 2. The anterior midgut also functions for nutrient absorption but plays a more important role in merocrine and exocrine secretion. The presence of concretions in cell types two and three of the anterior midgut suggest a role in excretion, water or ion regulation. 3. The posterior midgut functions mainly in absorption, though some holocrine secretion is evident.
Intermediate Phases, structural variance and network demixing in chalcogenides: the unusual case of group V sulfides
Creators: name: Boolchand, P.
name: Chen, Ping
name: Vempati, U.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We review Intermediate Phases (IPs) in chalcogenide glasses and provide a structural interpretation of these phases. In binary group IV selenides, IPs reside in the 2.40 < r < 2.54 range, and in binary group V selenides they shift to a lower r, in the 2.29< r < 2.40 range. Here r represents the mean coordination number of glasses. In ternary alloys containing equal proportions of group IV and V selenides, IPs are wider and encompass ranges of respective binary glasses. These data suggest that the local structural variance contributing to IP widths largely derives from four isostatic local structures of varying connectivity r; two include group V based quasi-tetrahedral (r = 2.29) and pyramidal (r = 2.40) units, and the other two are group IV based corner-sharing (r = 2.40) and edge-sharing (r = 2.67) tetrahedral units. Remarkably, binary group V (P, As) sulfides exhibit IPs that are shifted to even a lower r than their selenide counterparts; a result that we trace to excess Sn chains either partially (As-S) or completely (P-S) demixing from network backbone, in contrast to excess Sen chains forming part of the backbone in corresponding selenide glasses. In ternary chalcogenides of Ge with the group V elements (As, P), IPs of the sulfides are similar to their selenide counterparts, suggesting that presence of Ge serves to reign in the excess Sn chain fragments back in the backbone as in their selenide counterparts.
A macroscopic pedestrian model with variable maximal density
Creators: name: Bartoli, Laura
name: Cacace, Simone
name: Cristiani, Emiliano
name: Ferretti, Roberto
Publisher: name: arXiv
Year: 2024
Subjects: subject: Dynamical Systems (math.DS)
subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: In this paper we propose a novel macroscopic (fluid dynamics) model for describing pedestrian flow in low and high density regimes. The model is characterized by the fact that the maximal density reachable by the crowd - usually a fixed model parameter - is instead a state variable. To do that, the model couples a conservation law, devised as usual for tracking the evolution of the crowd density, with a Burgers-like PDE with a nonlocal term describing the evolution of the maximal density. The variable maximal density is used here to describe the effects of the psychological/physical pushing forces which are observed in crowds during competitive or emergency situations. Specific attention is also dedicated to the fundamental diagram, i.e., the function which expresses the relationship between crowd density and flux. Although the model needs a well defined fundamental diagram as known input parameter, it is not evident a priori which relationship between density and flux will be actually observed, due to the time-varying maximal density. An a posteriori analysis shows that the observed fundamental diagram has an elongated "tail" in the congested region, thus resulting similar to the concave/concave fundamental diagram with a "double hump" observed in real crowds. The main features of the model are investigated through 1D and 2D numerical simulations. The numerical code for the 1D simulation is freely available at https://gitlab.com/cristiani77/code_arxiv_2406.14649
Probing light sterile neutrinos in left-right symmetric models with displaced vertices and neutrinoless double beta decay
Creators: name: de Vries, Jordy
name: Dreiner, Herbi K.
name: Groot, Jelle
name: Günther, Julian Y.
name: Wang, Zeren Simon
Publisher: name: arXiv
Year: 2024
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: An investigation of relatively light (GeV-scale), long-lived right-handed neutrinos is performed within minimal left-right symmetric models using the neutrino-extended Standard Model Effective Field Theory framework. Light sterile neutrinos can be produced through rare decays of kaons, $D$-mesons, and $B$-mesons at the Large Hadron Collider (LHC) and the Long-Baseline Neutrino Facility (LBNF) of Fermilab. Their decays could result in displaced vertices, which can be reconstructed. By performing Monte-Carlo simulations, we assess the sensitivities of the future LHC far-detector experiments ANUBIS, CODEX-b, FACET, FASER(2), MoEDAL-MAPP1(2), MATHUSLA, the recently approved beam-dump experiment SHiP, and the upcoming neutrino experiment DUNE at the LBNF, to the right-handed gauge-boson mass $M_{W_R}$ as functions of neutrino masses. We find that DUNE and SHiP could be sensitive to right-handed gauge-boson masses up to $\sim 25$ TeV. We compare this reach to indirect searches such as neutrinoless double beta decay, finding that displaced-vertex searches are very competitive.
Nonvanishing of Kronecker coefficients for rectangular shapes
Creators: name: Bürgisser, Peter
name: Christandl, Matthias
name: Ikenmeyer, Christian
Publisher: name: arXiv
Year: 2009
Subjects: subject: Group Theory (math.GR)
subject: Quantum Physics (quant-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: 20C30

description: We prove that for any partition $(λ_1,...,λ_{d^2})$ of size $\ell d$ there exists $k\ge 1$ such that the tensor square of the irreducible representation of the symmetric group $S_{k\ell d}$ with respect to the rectangular partition $(k\ell,...,k\ell)$ contains the irreducible representation corresponding to the stretched partition $(kλ_1,...,kλ_{d^2})$. We also prove a related approximate version of this statement in which the stretching factor $k$ is effectively bounded in terms of $d$. This investigation is motivated by questions of geometric complexity theory.
description: Added Section 1.1 containing motivation coming from geometric complexity theory. Added a result on symmetric Kronecker coefficients. Fixed a bug that made the paper appear twice in v3
Upper critical field, penetration depth, and depinning frequency of the novel high-temperature superconductor LaFeAsO$_{0.9}$F$_{0.1}$ studied by microwave surface impedance
Creators: name: Narduzzo, A.
name: Grbić, M. S.
name: Požek, M.
name: Dulčić, A.
name: Paar, D.
name: Kondrat, A.
name: Hess, C.
name: Hellmann, I.
name: Klingeler, R.
name: Werner, J.
name: Köhler, A.
name: Behr, G.
name: Büchner, B.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Temperature and magnetic field dependent measurements of the microwave surface impedance of superconducting LaFeAsO$_{0.9}$F$_{0.1}$ (\Tc $\approx$ 26K) reveal a very large upper critical field ($B_{\rm c2} \approx 56$T) and a large value of the depinning frequency ($f_{0}\approx 6$GHz); together with an upper limit for the effective London penetration depth, $λ_{\rm eff} \le 200 \rm nm$, our results indicate a strong similarity between this system and the high-$T_{\rm c}$ superconducting cuprates.
description: 4 pages, 6 figures, minor corrections and rephrasing
A Precision Gyroscope from the Helicity of Light
Creators: name: Fedderke, Michael A.
name: Harnik, Roni
name: Kaplan, David E.
name: Posen, Sam
name: Rajendran, Surjeet
name: Serra, Francesco
name: Yakovlev, Vyacheslav P.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Optics (physics.optics)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We describe a gyroscope that measures rotation based on the effects of the rotation on the polarization of light. Rotation induces a differential phase shift in the propagation of left- and right-circularly polarized light and this phase shift can be measured in suitably designed interferometric setups. The signal in this setup is independent of the frequency of light, unlike various sources of noise such as vibrations, which cause phase shifts that depend on the frequency. Such vibrations are the practical limit on the sensitivity of conventional Sagnac-style optical interferometers that are typically used as gyroscopes. In the proposed setup, one can potentially mitigate this source of noise by simultaneously using two (or more) sources of light that have different frequencies. The signal in this setup scales with the total storage time of the light. Due to its frequency independence, it is thus most optimal to measure the signal using superconducting radio-frequency systems where the high finesse of the available cavities enables considerably longer storage times than is possible in an optical setup.
description: 16 pages, 1 figure. Published version
Gapless States Localized along a Staircase Edge in Second-Order Topological Insulators
Creators: name: Nagasato, Yuki
name: Takane, Yositake
name: Yoshimura, Yukinori
name: Hayashi, Shin
name: Nakanishi, Takeshi
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: A second-order topological insulator on a two-dimensional square lattice hosts zero-dimensional states inside a band gap. They are localized near $90^{\circ}$ and $270^{\circ}$ corners constituting an edge of the system. When the edge is in a staircase form consisting of these two corners, two families of edge states (i.e., one-dimensional states localized near the edge) appear as a result of the hybridization of zero-dimensional states. We identify symmetry that makes them gapless. We also show that a pair of nontrivial winding numbers associated with this symmetry guarantee a gapless spectrum of edge states, indicating that bulk--boundary correspondence holds in this topological insulator with a staircase edge.
description: 9 pages, 14 figures
Sign reversal of ac Josephson current in a ferromagnetic Josephson junction
Creators: name: Hikino, S.
name: Mori, M.
name: Takahashi, S.
name: Maekawa, S.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: The ac Josephson effect in a ferromagnetic Josephson junction, which is composed of two superconductors separated by a ferromagnetic metal (FM), is studied by a tunneling Hamiltonian and Green's function method. We obtain two types of superconducting phase dependent current, i.e., Josephson current and quasiparticle-pair-interference current (QPIC). These currents change their signs with thickness of the FM layer due to the 0-$π$ transition characteristic to the ferromagnetic Josephson junction. As a function of applied voltage, the Josephson critical current shows a logarithmic divergence called the Riedel peak at the gap voltage, while the QPIC shows a discontinuous jump. The Riedel peak reverses due to the 0-$π$ transition and disappears near the 0-$π$ transition point. The discontinuous jump in the QPIC also represents similar behaviors to the Riedel peak. These results are in contrast to the conventional ones.
description: 9 pages, 6 figures
Neutron Yield of Thermo Scientific P385 D-T Neutron Generator vs. Current and Voltage
Creators: name: Jeon, Jihye
name: Goldston, Robert J.
name: Gilson, Erik P.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: The Thermo Scientific P385 Neutron Generator is a compact neutron source, producing 14 MeV neutrons through the deuterium-tritium (DT) fusion reaction. For practical use, it is important to measure and preferably understand the dependence of the neutron production rate on the accelerator current and voltage. In this study, we evaluated neutron production with a neutron spectrometer (BTI N-Probe), a He-3 detector surrounded by HDPE shells (Nested Neutron Spectrometer, NNS), and two ZnS fast neutron scintillators (EJ-410) for both P385 A3082 and A3083 sealed tubes. We also predicted the neutron yield using the TRIM code, which calculates the trajectory and the energy loss of deuterons and tritons within the target. Experimental and theoretical results showed a linear dependence on beam current and a $\sim$3.5 power law dependence on the operating voltage. A series of NNS measurements, neutron spectrum from N-Probe and MCNP calculation showed that the A3083 and A3082 tubes provide a maximum neutron yield of $\sim 8.2 \times 10^8$ n/s and $\sim 4.5 \times 10^8$ n/s, respectively. We showed that tritium decay was not a significant contributor to this difference.
description: 5 pages, 5 figures, 2 tables
Onset of spontaneous beating and whirling in the follower force model of an active filament
Creators: name: Schnitzer, Ory
Publisher: name: arXiv
Year: 2024
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We study the onset of spontaneous dynamics in the follower force model of an active filament, wherein a slender elastic filament in a viscous liquid is clamped normal to a wall at one end and subjected to a tangential compressive force at the other. Clarke, Hwang and Keaveny (Phys. Rev. Fluids, to appear) have recently conducted a thorough investigation of this model using methods of computational dynamical systems; inter alia, they show that the filament first loses stability via a supercritical double-Hopf bifurcation, with periodic 'planar-beating' states (unstable) and 'whirling' states (stable) simultaneously emerging at the critical follower-force value. We complement their numerical study by carrying out a weakly nonlinear analysis close to this unconventional bifurcation, using the method of multiple scales. The main outcome is an 'amplitude equation' governing the slow modulation of small-magnitude oscillations of the filament in that regime. Analysis of this reduced-order model provides insights into the onset of spontaneous dynamics, including the creation of the nonlinear whirling states from particular superpositions of linear planar-beating modes as well as the selection of whirling over planar beating in three-dimensional scenarios.
Deposit of Red Blood Cells at low concentrations in evaporating droplets: central edge growth and potential applications
Creators: name: Sardari, Vahideh
name: Mohammadian, Mahsa
name: Asfia, Shima
name: Maurer, Felix
name: Örüm, Diana
name: Seemann, Ralf
name: John, Thomas
name: Kaestner, Lars
name: Wagner, Christian
name: Maleki, Maniya
name: Darras, Alexis
Publisher: name: arXiv
Year: 2024
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: Evaporation of blood droplets and diluted blood samples is a topic of intensive research, as it is seen as a possible low-cost tool for diagnosis. So far, samples with volume fraction down to a few percents of Red Blood Cells (RBCs) have been studied, and those were reportedly dominated by a ``coffee-ring'' deposit. In this study, samples with lower volume fractions have been used in order to study the growth of the evaporative deposit from sessile droplets more in details. We observed that blood samples and salt solutions with less than 1\% volume fraction of RBCs are dominated by a central deposit. We characterized the growth process of this central deposit by evaporating elongated drops, and determined that it is consistent with the Kardar-Parisi-Zhang process in the presence of quenched disorder. Our results showed a sensitivity of this deposit size to the fibrinogen concentration and shape of the RBCs, meaning that this parameter could be used to develop a new and cost-effective clinical marker for inflammation and RBC deformation.
description: 27 pages, 11 Figures
On Tunnelling Through the Black Hole Horizon
Creators: name: Belinski, V. A.
Publisher: name: arXiv
Year: 2009
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: It is shown here that there is no way for particle creation to occur by quantum tunneling through an infinitesimal neighborhood of the black hole horizon. This result is a trivial consequence of the regularity of the horizon, the equivalence principle and the general covariance of the relativistic theory of gravity. Moreover, we also confirm the less trivial statement that no particle creation by quantum tunneling through the black hole horizon is possible independent of the size of the presupposed tunneling domain.
description: 21 pages, new section is added