cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Main-Belt Comet P/2012 T1 (PANSTARRS)
Creators: name: Hsieh, Henry H.
name: Kaluna, Heather M.
name: Novakovic, Bojan
name: Yang, Bin
name: Haghighipour, Nader
name: Micheli, Marco
name: Denneau, Larry
name: Fitzsimmons, Alan
name: Jedicke, Robert
name: Kleyna, Jan
name: Veres, Peter
name: Wainscoat, Richard J.
name: Ansdell, Megan
name: Elliott, Garrett T.
name: Keane, Jacqueline V.
name: Meech, Karen J.
name: Moskovitz, Nicholas A.
name: Riesen, Timm E.
name: Sheppard, Scott S.
name: Sonnett, Sarah
name: Tholen, David J.
name: Urban, Laurie
name: Kaiser, Nick
name: Chambers, K. C.
name: Burgett, William S.
name: Magnier, Eugene A.
name: Morgan, Jeffrey S.
name: Price, Paul A.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: We present initial results from observations and numerical analyses aimed at characterizing main-belt comet P/2012 T1 (PANSTARRS). Optical monitoring observations were made between October 2012 and February 2013 using the University of Hawaii 2.2 m telescope, the Keck I telescope, the Baade and Clay Magellan telescopes, Faulkes Telescope South, the Perkins Telescope at Lowell Observatory, and the Southern Astrophysical Research (SOAR) telescope. The object's intrinsic brightness approximately doubles from the time of its discovery in early October until mid-November and then decreases by ~60% between late December and early February, similar to photometric behavior exhibited by several other main-belt comets and unlike that exhibited by disrupted asteroid (596) Scheila. We also used Keck to conduct spectroscopic searches for CN emission as well as absorption at 0.7 microns that could indicate the presence of hydrated minerals, finding an upper limit CN production rate of QCN<1.5x10^23 mol/s, from which we infer a water production rate of QH2O<5x10^25 mol/s, and no evidence of the presence of hydrated minerals. Numerical simulations indicate that P/2012 T1 is largely dynamically stable for >100 Myr and is unlikely to be a recently implanted interloper from the outer solar system, while a search for potential asteroid family associations reveal that it is dynamically linked to the ~155 Myr-old Lixiaohua asteroid family.
description: 15 pages, 4 figures, accepted for publication in ApJ Letters
On the behavior of $F$-signatures, splitting primes, and test modules under finite covers
Creators: name: Carvajal-Rojas, Javier
name: Stäbler, Axel
Publisher: name: arXiv
Year: 2019
Subjects: subject: Commutative Algebra (math.AC)
subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 13A35, 14B05

description: We give a comprehensive treatment on how $F$-signatures, splitting primes, splitting ratios, and test modules behave under finite covers. To this end, we expand on the notion of transposability along a section section of the relative canonical module as first introduced by K.~Schwede and K.~Tucker.
description: 39 pages, comments are more than welcome. v3: major revision: shortened proofs and sharpened results v4: improved exposition, final version
Novel charged charmoniumlike structures in the hidden-charm dipion decays of Y(4360)
Creators: name: Chen, Dian-Yong
name: Liu, Xiang
name: Matsuki, Takayuki
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Studying the hidden-charm dipion decays of the charmoniumlike state Y(4360), we show that there exist charged charmoniumlike structures near $D\bar{D}^*$ and $D^*\bar{D}^*$ thresholds in the $J/ψπ^+$, $ψ(2S)π^+$ and $h_c(1P)π^+$ invariant mass spectra of the corresponding hidden-charm dipion decays of Y(4360) using the {\it{Initial Single Pion Emission} mechanism}. We suggest to do further experimental study on these predicted charged enhancement structures, especially by BESIII, Belle, and the forthcoming BelleII.
description: 5 pages, 2 figures, 1 table. More discussions added. Accepted by Phys. Rev. D
The Sivers Asymmetry in Hadronic Dijet Production
Creators: name: Kang, Zhong-Bo
name: Lee, Kyle
name: Shao, Ding Yu
name: Terry, John
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We study the single spin asymmetry in the back-to-back dijet production in transversely polarized proton-proton collisions. Such an asymmetry is generated by the Sivers functions in the incoming polarized proton. We propose a QCD formalism in terms of the transverse momentum dependent parton distribution functions, which allow us to resum the large logarithms that arise in the perturbative calculations. We make predictions for the Sivers asymmetry of hadronic dijet production at the kinematic region that is relevant to the experiment at the Relativistic Heavy Ion Collider (RHIC). We further compute the spin asymmetries in the selected positive and negative jet charge bins, to separate the contributions from $u$- and $d$-quark Sivers functions. We find that both the sign and size of our numerical results are roughly consistent with the preliminary results from the STAR collaboration at the RHIC.
description: 26 pages, 5 figures, 4 tables, section on polarized hard functions rewritten and numerics updated, additional clarification and references added
The Canada-France High-z Quasar Survey: 1.2mm Observations
Creators: name: Omont, A.
name: Willott, C. J.
name: Beelen, A.
name: Bergeron, J.
name: Orellana, G.
name: Delorme, P.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We report 250 GHz (1.2 mm) observations of a sample of 20 QSOs at redshifts 5.8 = 0.41 +/-0.14 mJy; such a 2.9-sigma average detection is hardly meaningful. It would correspond to ~ 0.94+/-0.32 10^12 Lo, and an average star formation rate of a few 100's Mo/yr, depending on the IMF and a possible AGN contribution to . This is consistent with previous findings of Wang et al. (2011) on the far-infrared emission of z~6 QSOs and extends them toward optically fainter sources.
description: 6 pages, 1 figure, A&A in press
Example of quasianalytic contraction whose spectrum is a proper subarc of the unit circle
Creators: name: Gamal', Maria F.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Functional Analysis (math.FA)
subject: FOS: Mathematics
subject: 47A10, 47A15, 47A60

description: A partial answer on [KS2, Question 2] is given. Namely, an operator $R$ similar to a quasianalytic contraction whose quasianalytic spectral set is equal to its spectrum and is a proper subarc of the unit circle is constructed, but no estimates of $\|R^{-1}\|$ is given.
The perihelion of Mercury advance and the light bending calculated in (enhanced) Newton's theory
Creators: name: Abramowicz, M. A.
name: Horak, G. F. R. Ellis J.
name: Wielgus, M.
Publisher: name: arXiv
Year: 2013
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We show that results of a simple dynamical gedanken experiment interpreted according to standard Newton's gravitational theory, may reveal that three-dimensional space is curved. The experiment may be used to reconstruct the curved geometry of space, i.e. its non-Euclidean metric. The perihelion of Mercury advance and the light bending calculated from the Poisson equation and the equation of motion in the curved geometry have the correct (observed) values. Independently, we also show that Newtonian gravity theory may be enhanced to incorporate the curvature of three dimensional space by adding an extra equation which links the Ricci scalar with the density of matter. Like in Einstein's general relativity, matter is the source of curvature. In the spherically symmetric (vacuum) case, the metric of space 3gik that follows from this extra equation agrees, to the expected accuracy, with the metric measured by the Newtonian gedanken experiment mentioned above.
description: arXiv admin note: text overlap with arXiv:1212.0264
Non-Markovian effects in waveguide-mediated entanglement
Creators: name: Gonzalez-Ballestero, C.
name: Garcia-Vidal, F. J.
name: Moreno, Esteban
Publisher: name: arXiv
Year: 2013
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We study the generation and evolution of entanglement between two qubits coupled through one-dimensional waveguide modes. By using a complete quantum electrodynamical formalism we go beyond the Markovian approximation. The diagonalization of the hamiltonian is carried out, and a set of quasi-localized eigenstates is found. We show that when the qubit-waveguide coupling is increased, the Markov approximation is not anymore valid, and the generation of entanglement is worsened.
description: 13 pages, 7 figures
On Waring's problem: some consequences of Golubeva's method
Creators: name: Wooley, Trevor D.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Number Theory (math.NT)
subject: FOS: Mathematics
subject: 11P05, 11D85

description: We investigate sums of mixed powers involving two squares, two cubes, and various higher powers, concentrating on situations inaccessible to the Hardy-Littlewood method.
Scalable and Robust Community Detection with Randomized Sketching
Creators: name: Rahmani, Mostafa
name: Beckus, Andre
name: Karimian, Adel
name: Atia, George
Publisher: name: arXiv
Year: 2018
Subjects: subject: Social and Information Networks (cs.SI)
subject: Machine Learning (cs.LG)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences

description: This article explores and analyzes the unsupervised clustering of large partially observed graphs. We propose a scalable and provable randomized framework for clustering graphs generated from the stochastic block model. The clustering is first applied to a sub-matrix of the graph's adjacency matrix associated with a reduced graph sketch constructed using random sampling. Then, the clusters of the full graph are inferred based on the clusters extracted from the sketch using a correlation-based retrieval step. Uniform random node sampling is shown to improve the computational complexity over clustering of the full graph when the cluster sizes are balanced. A new random degree-based node sampling algorithm is presented which significantly improves upon the performance of the clustering algorithm even when clusters are unbalanced. This framework improves the phase transitions for matrix-decomposition-based clustering with regard to computational complexity and minimum cluster size, which are shown to be nearly dimension-free in the low inter-cluster connectivity regime. A third sampling technique is shown to improve balance by randomly sampling nodes based on spatial distribution. We provide analysis and numerical results using a convex clustering algorithm based on matrix completion.
Fluctuation Effects in the Pair-Annihilation Process with Lévy Dynamics
Creators: name: Homrighausen, Ingo
name: Winkler, Anton A.
name: Frey, Erwin
Publisher: name: arXiv
Year: 2013
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We investigate the density decay in the pair-annihilation process A+A->0 in the case when the particles perform anomalous diffusion on a cubic lattice. The anomalous diffusion is realized via Lévy flights, which are characterized by long-range jumps and lead to superdiffusive behavior. As a consequence, the critical dimension depends continuously on the control parameter of the Lévy flight distribution. This instance is used to study the system close to the critical dimension by means of the nonperturbative renormalization group theory. Close to the critical dimension, the assumption of well-stirred reactants is violated by anticorrelations between the particles, and the law of mass action breaks down. The breakdown of the law of mass action is known to be caused by long-range fluctuations. We identify three interrelated consequences of these fluctuations. First, despite being a nonuniversal quantity and thus depending on the microscopic details, the renormalized reaction rate can be approximated by a universal law close to the critical dimension. The emergence of universality relies on the fact that long-range fluctuations suppress the influence of the underlying microscopic details. Second, as criticality is approached, the macroscopic reaction rate decreases such that the law of mass action loses its significance. And third, additional nonanalytic power law corrections complement the analytic law of mass action term. An increasing number of those corrections accumulate and give an essential contribution as the critical dimension is approached. We test our findings for two implementations of Lévy flights that differ in the way they cross over to the normal diffusion.
description: 15 pages, 8 figures; corrected typos
Studies of NGC 6720 with Calibrated HST WFC3 Emission-Line Filter Images--I: Structure and Evolution
Creators: name: O'Dell, C. R.
name: Ferland, G. J.
name: Henney, W. J.
name: Peimbert, Manuel
Publisher: name: arXiv
Year: 2013
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We have performed a detailed analysis of the Ring Nebula (NGC 6720) using HST WFC3 images and derived a new 3-D model. Existing high spectral resolution spectra played an important supplementary role in our modeling. It is shown that the Main Ring of the nebula is an ionization-bounded irregular non-symmetric disk with a central cavity and perpendicular extended lobes pointed almost towards the observer. The faint outer halos are determined to be fossil radiation, i.e. radiation from gas ionized in an earlier stage of the nebula when it was not ionization bounded. The narrow-band WFC3 filters that isolate some of the emission-lines are affected by broadening on their short wavelength side and all the filters were calibrated using ground-based spectra. The filter calibration results are presented in an appendix.
description: Accepted for publication by the Astronomical Journal
title: Erucasäure: BfR befürwortet vorgeschlagene Höchstgehalte - jedoch sollten auch Lebensmittel mit zugesetzten Fetten begrenzt werden: Stellungnahme Nr. 044/2018 des BfR vom 20. Dezember 2018
Creators: name: Bundesinstitut Für Risikobewertung
Publisher: name: Bundesbehörden und Einrichtungen im Geschäftsbereich des Bundesministeriums für Ernährung und Landwirtschaft (BMEL)
Year: 2018
Subjects: subject: 000

description: BfR-Stellungnahmen, vol. 2018, no. 044
Global analysis of the Sivers functions at NLO+NNLL in QCD
Creators: name: Echevarria, Miguel G.
name: Kang, Zhong-Bo
name: Terry, John
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We perform global fit to the quark Sivers function within the transverse momentum dependent (TMD) factorization formalism in QCD. We simultaneously fit Sivers asymmetry data from Semi-Inclusive Deep Inelastic Scattering (SIDIS) at COMPASS, HERMES, and JLab, from Drell-Yan lepton pair production at COMPASS, and from $W/Z$ boson at RHIC. This extraction is performed at next-to-leading order (NLO) and next-to-next-to leading logarithmic (NNLL) accuracy. We find excellent agreement between our extracted asymmetry and the experimental data for SIDIS and Drell-Yan lepton pair production, while tension arises when trying to describe the spin asymmetries of $W/Z$ bosons at RHIC. We carefully assess the situation, and we study in details the impact of the RHIC data and their implications through different ways of performing the fit. In addition, we find that the quality of the description of $W/Z$ vector boson asymmetry data could be strongly sensitive to the DGLAP evolution of Qiu-Sterman function, besides the usual TMD evolution. We present discussion on this and the implications for measurements of the transverse-spin asymmetries at the future Electron Ion Collider.
description: 48 pages, 21 figures
Resonances on hedgehog manifolds
Creators: name: Exner, Pavel
name: Lipovsky, Jiri
Publisher: name: arXiv
Year: 2013
Subjects: subject: Mathematical Physics (math-ph)
subject: Spectral Theory (math.SP)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences
subject: FOS: Mathematics
subject: 81Q35

description: We discuss resonances for a nonrelativistic and spinless quantum particle confined to a two- or three-dimensional Riemannian manifold to which a finite number of semiinfinite leads is attached. Resolvent and scattering resonances are shown to coincide in this situation. Next we consider the resonances together with embedded eigenvalues and ask about the high-energy asymptotics of such a family. For the case when all the halflines are attached at a single point we prove that all resonances are in the momentum plane confined to a strip parallel to the real axis, in contrast to the analogous asymptotics in some metric quantum graphs; we illustrate it on several simple examples. On the other hand, the resonance behaviour can be influenced by a magnetic field. We provide an example of such a `hedgehog' manifold at which a suitable Aharonov-Bohm flux leads to absence of any true resonance, i.e. that corresponding to a pole outside the real axis.
Quantum error correction of a qubit encoded in grid states of an oscillator
Creators: name: Campagne-Ibarcq, P.
name: Eickbusch, A.
name: Touzard, S.
name: Zalys-Geller, E.
name: Frattini, N. E.
name: Sivak, V. V.
name: Reinhold, P.
name: Puri, S.
name: Shankar, S.
name: Schoelkopf, R. J.
name: Frunzio, L.
name: Mirrahimi, M.
name: Devoret, M. H.
Publisher: name: arXiv
Year: 2019
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Quantum bits are more robust to noise when they are encoded non-locally. In such an encoding, errors affecting the underlying physical system can then be detected and corrected before they corrupt the encoded information. In 2001, Gottesman, Kitaev and Preskill (GKP) proposed a hardware-efficient instance of such a qubit, which is delocalised in the phase-space of a single oscillator. However, implementing measurements that reveal error syndromes of the oscillator while preserving the encoded information has proved experimentally challenging: the only realisation so far relied on post-selection, which is incompatible with quantum error correction (QEC). The novelty of our experiment is precisely that it implements these non-destructive error-syndrome measurements for a superconducting microwave cavity. We design and implement an original feedback protocol that incorporates such measurements to prepare square and hexagonal GKP code states. We then demonstrate QEC of an encoded qubit with unprecedented suppression of all logical errors, in quantitative agreement with a theoretical estimate based on the measured imperfections of the experiment. Our protocol is applicable to other continuous variable systems and, in contrast with previous implementations of QEC, can mitigate all logical errors generated by a wide variety of noise processes, and open a way towards fault-tolerant quantum computation.
description: Text and figures edited for clarity. The claims of the paper remain the same. Author list fixed
The XXZ Heisenberg model on random surfaces
Creators: name: Ambjorn, J.
name: Sedrakyan, A.
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We consider integrable models, or in general any model defined by an $R$-matrix, on random surfaces, which are discretized using random Manhattan lattices. The set of random Manhattan lattices is defined as the set dual to the lattice random surfaces embedded on a regular d-dimensional lattice. They can also be associated with the random graphs of multiparticle scattering nodes. As an example we formulate a random matrix model where the partition function reproduces the annealed average of the XXZ Heisenberg model over all random Manhattan lattices. A technique is presented which reduces the random matrix integration in partition function to an integration over their eigenvalues.
description: 15 pages
TOF-PET detector concept based on organic scintillators
Creators: name: Moskal, P.
name: Bednarski, T.
name: Białas, P.
name: Ciszewska, M.
name: Czerwiński, E.
name: Heczko, A.
name: Kajetanowicz, M.
name: Kapłon, Ł.
name: Kochanowski, A.
name: Konopka-Cupiał, G.
name: Korcyl, G.
name: Krzemień, W.
name: Łojek, K.
name: Majewski, J.
name: Migdał, W.
name: Molenda, M.
name: Niedźwiecki, Sz.
name: Pałka, M.
name: Rudy, Z.
name: Salabura, P.
name: Silarski, M.
name: Słomski, A.
name: Smyrski, J.
name: Zdebik, J.
name: Zieliński, M.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: High Energy Physics - Experiment (hep-ex)
subject: Nuclear Experiment (nucl-ex)
subject: Medical Physics (physics.med-ph)
subject: FOS: Physical sciences

description: In this contribution we present a new concept of the large acceptance detector systems based on organic scintillators which may allow for simultaneous diagnostic of large fraction of the human body. Novelty of the concept lies in employing large blocks of polymer scintillators instead of crystals as detectors of annihilation quanta, and in using predominantly the timing of signals instead of their amplitudes.
description: Proceedings of the Positron Emission Tomography in Research and Diagnostics conference, Warsaw 16 - 19 May, 2012
Supervised Learning and Reinforcement Learning of Feedback Models for Reactive Behaviors: Tactile Feedback Testbed
Creators: name: Sutanto, Giovanni
name: Rombach, Katharina
name: Chebotar, Yevgen
name: Su, Zhe
name: Schaal, Stefan
name: Sukhatme, Gaurav S.
name: Meier, Franziska
Publisher: name: arXiv
Year: 2020
Subjects: subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: Robots need to be able to adapt to unexpected changes in the environment such that they can autonomously succeed in their tasks. However, hand-designing feedback models for adaptation is tedious, if at all possible, making data-driven methods a promising alternative. In this paper we introduce a full framework for learning feedback models for reactive motion planning. Our pipeline starts by segmenting demonstrations of a complete task into motion primitives via a semi-automated segmentation algorithm. Then, given additional demonstrations of successful adaptation behaviors, we learn initial feedback models through learning from demonstrations. In the final phase, a sample-efficient reinforcement learning algorithm fine-tunes these feedback models for novel task settings through few real system interactions. We evaluate our approach on a real anthropomorphic robot in learning a tactile feedback task.
description: Accepted for publication in the International Journal of Robotics Research (IJRR). Paper length is 22 pages (including references) with 12 figures. A video overview of the reinforcement learning experiment on the real robot can be seen at https://www.youtube.com/watch?v=yu5v-ZXo4-E. arXiv admin note: text overlap with arXiv:1710.08555
Spectrum of Lebesgue measure zero for Jacobi matrices of quasicrystals
Creators: name: Beckus, Siegfried
name: Pogorzelski, Felix
Publisher: name: arXiv
Year: 2013
Subjects: subject: Mathematical Physics (math-ph)
subject: Spectral Theory (math.SP)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We study one-dimensional random Jacobi operators corresponding to strictly ergodic dynamical systems. In this context, we characterize the spectrum of these operators by non-uniformity of the transfer matrices and the set where the Lyapunov exponent vanishes. Adapting this result to subshifts satisfying the so-called Boshernitzan condition, it turns out that the spectrum is supported on a Cantor set with Lebesgue measure zero. This generalizes earlier results for Schrödinger operators.
description: 18 pages
An Algorithmic Approach for Identifying Critical Distance Relays for Transient Stability Studies
Creators: name: Vakili, Ramin
name: Khorsand, Mojdeh
name: Vittal, Vijay
name: Robertson, Bill
name: Augustin, Philip
Publisher: name: arXiv
Year: 2020
Subjects: subject: Systems and Control (eess.SY)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: After major disturbances, power system behavior is governed by the dynamic characteristics of its assets and protection schemes. Therefore, modeling protection devices is essential for performing accurate stability studies. Modeling all the protection devices in a bulk power system is an intractable task due to the limitations of current stability software, and the difficulty of maintaining and updating the data for thousands of protection devices. One of the critical protection schemes that is not adequately modeled in stability studies is distance relaying. Therefore, this paper proposes an algorithm that uses two methods to identify the critical distance relays to be modeled in stability studies: (i) apparent impedance monitoring, and (ii) the minimum voltage evaluation (MVE). The algorithm is implemented in Python 3.6 and uses the GE positive sequence load flow analysis (PSLF) software for performing stability studies. The performance of the algorithm is evaluated on the Western Electricity Coordinating Council (WECC) system data representing the 2018 summer-peak load. The results of the case studies representing various types of contingencies show that to have an accurate assessment of system behavior, modeling the critical distance relays identified by the algorithm suffices, and there is no need for modeling all the distance relays.
Generalized permutahedra and Schubert calculus
Creators: name: Dizier, Avery St.
name: Yong, Alexander
Publisher: name: arXiv
Year: 2020
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics

description: We connect generalized permutahedra with Schubert calculus. Thereby, we give sufficient vanishing criteria for Schubert intersection numbers of the flag variety. Our argument utilizes recent developments in the study of Schubitopes, which are Newton polytopes of Schubert polynomials. The resulting tableau test executes in polynomial time.
description: 13 pages
Recent developments concerning generic spacelike singularities
Creators: name: Uggla, Claes
Publisher: name: arXiv
Year: 2013
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: This is a review of recent progress concerning generic spacelike singularities in general relativity. For brevity the main focus is on singularities in vacuum spacetimes, although the connection with, and the role of, matter for generic singularity formation is also commented on. The paper describes recent developments in two areas and show how these are connected within the context of the conformally Hubble-normalized state space approach. The first area is oscillatory singularities in spatially homogeneous cosmology and the connection between asymptotic behaviour and heteroclinic chains. The second area concerns oscillatory singularities in inhomogeneous models, especially spike chains and recurring spikes. The review also outlines some underlying reasons for why the structures that are the foundation for generic oscillatory behaviour exists at all, which entails discussing how underlying physical principles and applications of solution generating techniques yield hierarchical structures and connections between them. Finally, it is pointed out that recent progress concerning generic singularities motivates some speculations that suggest that a paradigm shift concerning their physical role, and what mathematical issues to address, might be in order.
description: 32 pages; plenary contribution to ERE2012
title: The Effect of Iron Supplementation on the Endurance Capacity of the Female College Athlete
Creators: name: Sachon, Barbara B.
Publisher: name: Old Dominion University
publisherIdentifier: https://ror.org/04zjtrb98
publisherIdentifierScheme: ROR
Year: 1975

description: The major parameter of interest was the effect of iron supplementation on endurance capacity of female college athletes. Secondary parameters included the evaluation of the effect of iron supplementation on the following hematological variables: white blood cell count, red blood cell count, hemoglobin concentration, and hematocrit. Nineteen volunteer female students enrolled at the College of William and Mary in Williamsburg, Virginia served as subjects, All were members of the swimming team. All test trials and venipunctures were done at the women's gym at the College of William and Mary. There were two test periods.

All nineteen subjects performed a 500 yard freestyle swim as a performance measure. Based on times of the initial performance test, two groups were formed. The principles underlying a double-blind placebo experiment were utilized. The experimental group received J24 mg of ferrous sulfate and the placebo group received J24 mg of lactose in capsule form. Both groups took one unit daily for a period of 28 days. Neither group knew which supplement they had received and both groups believed they were taking an iron supplement. After a 28 day period, the subjects were retested on the 500 yard swim.

A subgroup of twelve of the nineteen subjects consented to venipuncture for blood analysis. Six of these subjects were in the iron supplement group and six in the placebo group. Venipuncture was performed twice, both times immediately prior to endurance testing. A blood analysis of white blood cell count, red blood cell count, hemoglobin and hematocrit was done.

Within group differences were analyzed by use of the t-test. Significance was declared if the statistic met or exceeded an alpha level of .05. There was no significant difference in the placebo group for red blood cell count, white blood cell count, hemoglobin or hematocrit. There was a significant increase in endurance. In the iron group, a significant increase was found for the white blood cell count and the red blood cell count; hematocrit was found to significantly decrease, and hemoglobin and endurance did not change significantly.

Between group differences were analyzed by use of the analysis of covariance. Significance was declared if the statistic met or exceeded an alpha level of .05. It was found that there was a significant improvement in endurance capacity for the placebo group. There was no significant difference in white blood cell count, red blood cell count, hemoglobin or hematocrit between the placebo and iron group.

Within the limitations of this study, it was found that iron supplementation had no effect on endurance capacity.
An autoencoder-based reduced-order model for eigenvalue problems with application to neutron diffusion
Creators: name: Phillips, Toby
name: Heaney, Claire E.
name: Smith, Paul N.
name: Pain, Christopher C.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Numerical Analysis (math.NA)
subject: Machine Learning (cs.LG)
subject: Computational Physics (physics.comp-ph)
subject: Machine Learning (stat.ML)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: Using an autoencoder for dimensionality reduction, this paper presents a novel projection-based reduced-order model for eigenvalue problems. Reduced-order modelling relies on finding suitable basis functions which define a low-dimensional space in which a high-dimensional system is approximated. Proper orthogonal decomposition (POD) and singular value decomposition (SVD) are often used for this purpose and yield an optimal linear subspace. Autoencoders provide a nonlinear alternative to POD/SVD, that may capture, more efficiently, features or patterns in the high-fidelity model results. Reduced-order models based on an autoencoder and a novel hybrid SVD-autoencoder are developed. These methods are compared with the standard POD-Galerkin approach and are applied to two test cases taken from the field of nuclear reactor physics.
description: 35 pages, 33 figures
Quarkonium Results in PbPb Collisions at CMS
Creators: name: Sánchez, Manuel Calderón de la Barca
Publisher: name: arXiv
Year: 2013
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: We summarize the results from the study of charmonium and bottomonium via the dimuon decay channel in PbPb collisions with the CMS experiment. We discuss the observation of sequential suppression of the Upsilon states. We present preliminary results of prompt J/psi and psi' production, as well as of non-prompt J/psis coming from the weak decay of b-quarks. This latter measurement is sensitive to b-quark energy loss. We discuss the results and compare to model predictions.
description: 8 pages, 4 figures. Proceedings of 29th Winter Workshop on Nuclear Dynamics
Black Hole Horizons as Patternless Binary Messages and Markers of Dimensionality
Creators: name: Łukaszyk, Szymon
Publisher: name: arXiv
Year: 2019
Subjects: subject: General Physics (physics.gen-ph)
subject: FOS: Physical sciences

description: This study aims to reconcile quantum theory with the universality of the speed of light in vacuum and its implications on relativity through an information-theoretic approach. We introduce the concepts of a holographic sphere and variational potential. Entropy variation expressed in terms of the information capacity of this sphere results in the concept of binary potential in units of negative, squared speed of light in vacuum. Accordingly, the event horizon is a fundamental holographic sphere in thermodynamic equilibrium with only one exterior side: a noncompressible binary message that maximizes Shannon entropy. Therefore, the Jordan-Brouwer separation theorem and generalized Stokes theorem do not hold for black holes. We introduce the concept of inertial potential and demonstrate its equivalence to the variational potential, which ensures that any inertial acceleration represents a nonequilibrium thermodynamic condition. We introduce the concept of the complementary time period and relate it with the classical time period through integral powers of the imaginary unit to formulate the notions of unobservable velocity and acceleration, which are perpendicular and tangential to the holographic sphere, respectively, and bound with the observable velocity and acceleration based on Pythagorean relations. We further discuss certain dynamics scenarios between the two masses. The concept of black hole informationless emission is introduced as a complement to informationless Bekenstein absorption and extended to arbitrary wavelengths. Black hole quantum statistics with degeneracy interpreted as the number of Planck areas on the event horizon are discussed. The study concludes that holographic screens and equipotential surfaces are spherical equivalents, and every observer is a sphere in nonequilibrium thermodynamic condition. Lastly, we propose a solution to the black hole information paradox.
description: Future Relativity, Gravitation, Cosmology, Nova Science Publishers, Inc
Resonant Behavior of Comet Halley and the Orionid Stream
Creators: name: Sekhar, Aswin
name: Asher, David J
Publisher: name: arXiv
Year: 2013
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Comet 1P/Halley has the unique distinction of having a very comprehensive set of observational records for almost every perihelion passage from 240 B.C. This has helped to constrain theoretical models pertaining to its orbital evolution. Many previous works have shown the active role of mean motion resonances in the evolution of various meteoroid streams. Here we look at how various resonances, especially the 1:6 and 2:13 mean motion resonances with Jupiter, affect comet 1P/Halley and thereby enhance the chances of meteoroid particles getting trapped in resonance, leading to meteor outbursts in some particular years. Comet Halley itself librated in the 2:13 resonance from 240 B.C. to 1700 A.D. and in the 1:6 resonance from 1404 B.C. to 690 B.C., while stream particles can survive for timescales of the order of 10,000 years and 1,000 years in the 1:6 and 2:13 resonances respectively. This determines the long term dynamical evolution and stream structure, influencing the occurrence of Orionid outbursts. Specifically we are able to correlate the occurrence of enhanced meteor phenomena seen between 1436-1440, 1933-1938 & 2006-2010 with the 1:6 resonance and meteor outbursts in 1916 & 1993 with the 2:13 resonance. Ancient as well as modern observational records agree with these theoretical simulations to a very good degree.
description: 19 pages, 10 figures, 1 table (Accepted by Meteoritics & Planetary Science)
Failure of the Brauer-Manin principle for a simply connected fourfold over a global function field, via orbifold Mordell
Creators: name: Kebekus, Stefan
name: Pereira, Jorge Vitório
name: Smeets, Arne
Publisher: name: arXiv
Year: 2019
Subjects: subject: Algebraic Geometry (math.AG)
subject: Number Theory (math.NT)
subject: FOS: Mathematics
subject: 14F22 (11G35)

description: Almost one decade ago, Poonen constructed the first examples of algebraic varieties over global fields for which Skorobogatov's etale Brauer-Manin obstruction does not explain the failure of the Hasse principle. By now, several constructions are known, but they all share common geometric features such as large fundamental groups. In this paper, we construct simply connected fourfolds over global fields of positive characteristic for which the Brauer-Manin machinery fails. Contrary to earlier work in this direction, our construction does not rely on major conjectures. Instead, we establish a new diophantine result of independent interest: a Mordell-type theorem for Campana's "geometric orbifolds" over function fields of positive characteristic. Along the way, we also construct the first example of simply connected surface of general type over a global field with a non-empty, but non-Zariski dense set of rational points.
description: Final version. To appear in the Duke Mathematical Journal
Quasi-phase-matching of high-order-harmonic generation using multimode polarization beating
Creators: name: Liu, Lewis Z.
name: O'Keeffe, Kevin
name: Hooker, Simon M.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: The generalization of quasi-phase-matching using polarization beating and of multimode quasi-phase-matching (MMQPM) for the generation of high-order harmonics is explored, and a method for achieving polarization beating is proposed. If two (and in principle more) modes of a waveguide are excited, modulation of the intensity, phase, and/or polarization of the guided radiation will be achieved. By appropriately matching the period of this modulation to the coherence length, quasi-phase-matching of high-order-harmonic radiation generated by the guided wave can occur. We show that it is possible to achieve efficiencies with multimode quasi-phase-matching greater than the ideal square wave modulation. We present a Fourier treatment of QPM and use this to show that phase modulation, rather than amplitude modulation, plays the dominant role in the case of MMQPM. The experimental parameters and optimal conditions for this scheme are explored.
Efficient Optimization of Dominant Set Clustering with Frank-Wolfe Algorithms
Creators: name: Johnell, Carl
name: Chehreghani, Morteza Haghir
Publisher: name: arXiv
Year: 2020
Subjects: subject: Machine Learning (cs.LG)
subject: Optimization and Control (math.OC)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: We study Frank-Wolfe algorithms - standard, pairwise, and away-steps - for efficient optimization of Dominant Set Clustering. We present a unified and computationally efficient framework to employ the different variants of Frank-Wolfe methods, and we investigate its effectiveness via several experimental studies. In addition, we provide explicit convergence rates for the algorithms in terms of the so-called Frank-Wolfe gap. The theoretical analysis has been specialized to Dominant Set Clustering and covers consistently the different variants.
description: Accepted at CIKM 2022. Sole copyright holder is ACM - CIKM (ACM International Conference on Information & Knowledge Management), all rights reserved. Available at https://dl.acm.org/doi/10.1145/3511808.3557306
Variable pulse profiles of Her X-1 repeating with the same irregular 35d clock as the turn-ons
Creators: name: Staubert, R.
name: Klochkov, D.
name: Vasco, D.
name: Postnov, K.
name: Shakura, N.
name: Wilms, J.
name: Rothschild, R. E.
Publisher: name: arXiv
Year: 2012
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The accreting X-ray pulsar Her X-1 shows two types of long-term variations, both with periods of ~35 days: 1) Turn-on cycles, a modulation of the flux}, with a ten-day long Main-On and a five-day long Short-On, separated by two Off-states, and 2) a systematic variation in the shape of the 1.24 s pulse profile. While there is general consensus that the flux modulation is due to variable shading of the X-ray emitting regions on the surface of the neutron star by the precessing accretion disk, the physical reason for the variation in the pulse profiles has remained controversial. Following the suggestion that free precession of the neutron star may be responsible for the variation in the pulse profiles, we developed a physical model of strong feedback interaction between the neutron star and the accretion disk in order to explain the seemingly identical values for the periods of the two types of variations, which were found to be in basic synchronization. In a deep analysis of pulse profiles observed by several different satellites over the last three decades we now find that the clock behind the pulse profile variations shows exactly the same erratic behavior as the turn-on clock, even on short time scales (a few 35 d cycles), suggesting that there may in fact be only one 35 d clock in the system. If this is true, it raises serious questions with respect to the idea of free precession of the neutron star, namely how the neutron star can change its precessional period every few years by up to 2.5% and how the feedback can be so strong, such that these changes can be transmitted to the accretion disk on rather short time scales.
description: 9 pages, 13 figures, accepted by Astronomy & Astrophysics. arXiv admin note: substantial text overlap with arXiv:1110.6717
STRIP-PET: a novel detector concept for the TOF-PET scanner
Creators: name: Moskal, P.
name: Bednarski, T.
name: Białas, P.
name: Ciszewska, M.
name: Czerwiński, E.
name: Heczko, A.
name: Kajetanowicz, M.
name: Kapłon, Ł.
name: Kochanowski, A.
name: Konopka-Cupiał, G.
name: Korcyl, G.
name: Krzemień, W.
name: Łojek, K.
name: Majewski, J.
name: Migdał, W.
name: Molenda, M.
name: Niedźwiecki, Sz.
name: Pałka, M.
name: Rudy, Z.
name: Salabura, P.
name: Silarski, M.
name: Słomski, A.
name: Smyrski, J.
name: Zdebik, J.
name: Zieliński, M.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: High Energy Physics - Experiment (hep-ex)
subject: Nuclear Experiment (nucl-ex)
subject: Medical Physics (physics.med-ph)
subject: FOS: Physical sciences

description: We briefly present a design of a new PET scanner based on strips of polymer scintillators arranged in a barrel constituting a large acceptance detector. The solution proposed is based on the superior timing properties of the polymer scintillators. The position and time of the reaction of the gamma quanta in the detector material will be determined based on the time of arrival of light signals to the edges of the scintillator strips.
description: Proceedings of the Positron Emission Tomography in Research and Diagnostics conference, Warsaw 16 - 19 May, 2012
Probing modified gravity theories with the Sandage-Loeb test
Creators: name: Li, Zhengxiang
name: Liao, Kai
name: Wu, Puxun
name: Yu, Hongwei
name: Zhu, Zong-Hong
Publisher: name: arXiv
Year: 2013
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: In this paper, we quantify the ability of a future measurement of the Sandage-Loeb test signal from the Cosmic-Dynamic-Experiment-like spectrograph to constrain some popular modified gravity theories including DGP brane-world scenario, $f(R)$ modified gravity and $f(T)$ gravity theory. We find that the Sandage-Loeb test measurements are able to break degeneracies between model parameters markedly and thus greatly improve cosmological constraints for all concerned modified gravity theories when combined with the latest observations of CMB--shift parameter. However, they yield almost the same degeneracy directions between model parameters as that from the distance ratio data derived from the latest observations of the cosmic microwave background and baryonic acoustic oscillations (CMB/BAO). Moreover, for the $f(R)$ modified gravity, the Sandage-Loeb test could provide completely different bounded regions in model parameters space as compared to CMB/BAO and thus supplement strong complementary constraints.
description: 18 pages, 6 figures, typos corrected and three references added, to be published in Phys. Rev. D
Studies of NGC 6720 with Calibrated HST WFC3 Emission-Line Filter Images--II:Physical Conditions
Creators: name: O'Dell, C. R.
name: Ferland, G. J.
name: Henney, W. J.
name: Peimbert, Manuel
Publisher: name: arXiv
Year: 2013
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We have performed a detailed analysis of the electron temperature and density in the the Ring Nebula using the calibrated HST WFC3 images described in the preceding paper. The electron temperature (Te) determined from [N II] and [O III] rises slightly and monotonically towards the central star. The observed equivalent width (EW) in the central region indicates that Te rises as high as 13000 K. In contrast, the low EW's in the outer regions are largely due to scattered diffuse Galactic radiation by dust. The images allowed determination of unprecedented small scale variations in Te. These variations indicate that the mean square area temperature fluctuations are significantly higher than expected from simple photoionization. The power producing these fluctuations occurs at scales of less than 3.5E15 cm. This scale length provides a strong restriction on the mechanism causing the large t^2 values observed.
description: Accepted for publication in the Astronomical Journal
Does a hadron-quark phase transition in dense matter preclude the existence of massive neutron stars ?
Creators: name: Chamel, N.
name: Fantina, A. F.
name: Pearson, J. M.
name: Goriely, S.
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We study the impact of a hadron-quark phase transition on the maximum neutron-star mass. The hadronic part of the equation of state relies on the most up-to-date Skyrme nuclear energy density functionals, fitted to essentially all experimental nuclear mass data and constrained to reproduce the properties of infinite nuclear matter as obtained from microscopic calculations using realistic forces. We show that the softening of the dense matter equation of state due to the phase transition is not necessarily incompatible with the existence of massive neutron stars like PSR J1614-2230.
description: Proceedings of IAUS 291 "Neutron Stars and Pulsars: Challenges and Opportunities after 80 years", J. van Leeuwen (ed.); 3 pages, 1 figure