cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Total Angular Momentum Conservation During Tunnelling through Semiconductor Barriers
Creators: name: Gennser, U.
name: Scheinert, M.
name: Diehl, L.
name: Tsujino, S.
name: Borak, A.
name: Falub, C. V.
name: Grützmacher, D.
name: Weber, A.
name: Maude, D. K.
name: Campidelli, Y.
name: Kermarrec, O.
name: Bensahel, D.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We have investigated the electrical transport through strained p-Si/Si_{1-x}Ge_x double-barrier resonant tunnelling diodes. The confinement shift for diodes with different well width, the shift due to a central potential spike in a well, and magnetotunnelling spectroscopy demonstrate that the first two resonances are due to tunnelling through heavy hole levels, whereas there is no sign of tunnelling through the first light hole state. This demonstrates for the first time the conservation of the total angular momentum in valence band resonant tunnelling. It is also shown that conduction through light hole states is possible in many structures due to tunnelling of carriers from bulk emitter states.
description: 4 pages, 4 figures
The Undecidable Charge Gap and the Oil Drop Experiment
Creators: name: Majhi, Abhishek
Publisher: name: arXiv
Year: 2024
Subjects: subject: General Physics (physics.gen-ph)
subject: FOS: Physical sciences

description: Decision problems in physics have been an active field of research for quite a few decades resulting in some interesting findings in recent years. However, such research investigations are based on a priori knowledge of theoretical computer science and the technical jargon of set theory. Here, I discuss a particular, but a significant, instance of how decision problems in physics can be realized without such specific prerequisites. I expose a hitherto unnoticed contradiction, that can be posed as a decision problem, concerning the oil drop experiment and thereby resolve it by refining the notion of ``existence'' in physics. This consequently leads to the undecidability of the charge spectral gap through the notion of ``undecidable charges" which is in tandem with the completeness condition of a theory as was stated by Einstein, Podolsky and Rosen in their seminal work. Decision problems can now be realized in connection to basic physics, in general, rather than quantum physics, in particular, as per some recent claims.
description: 14 pages, 1 figure
Entfernung zweier Sterne
Creators: name: Schröer, Harald
Publisher: name: Zenodo
Year: 2021
Subjects: Kosinussatz, Seitenkosinussatz, Trigonometrie, Rektaszension,Deklination,sphärische Trigonometrie,Entfernung

description: Die Entfernung von zwei Fixsternen wird berechnet, mit Hilfe der Kosinussätze.
Petri Nets for Smart Grids: The Story So Far
Creators: name: Ge, Mouzhi
name: Rossi, Bruno
name: Chren, Stanislav
name: Blanco, José Miguel
Publisher: name: arXiv
Year: 2024
Subjects: subject: Other Computer Science (cs.OH)
subject: FOS: Computer and information sciences

description: Since the energy domain is in a transformative shift towards sustainability, the integration of new technologies and smart systems into traditional power grids has emerged. As an effective approach, Petri Nets (PN) have been applied to model and analyze the complex dynamics in Smart Grid (SG) environments. However, we are currently missing an overview of types of PNs applied to different areas and problems related to SGs. Therefore, this paper proposes four fundamental research questions related to the application areas of PNs in SGs, PNs types, aspects modelled by PNs in the identified areas, and the validation methods in the evaluation. The answers to the research questions are derived from a comprehensive and interdisciplinary literature analysis. The results capture a valuable overview of PNs applications in the global energy landscape and can offer indications for future research directions.
6RLR-ABC: 6LoWPAN Routing Protocol With Local Repair Using Bio Inspired Artificial Bee Colony
Creators: name: Ismail, Nurul Halimatul Asmak
name: Awwad, Samer A. B.
name: Hassan, Rosilah
Publisher: name: arXiv
Year: 2020
Subjects: subject: Networking and Internet Architecture (cs.NI)
subject: Emerging Technologies (cs.ET)
subject: FOS: Computer and information sciences

description: In recent years, Micro-Electro-Mechanical System (MEMS) has successfully enabled the development of IPv6 over Low power Wireless Personal Area Network (6LoWPAN). This network is equipped with low-cost, low-power, lightweight and varied functions devices. These devices are capable of amassing, storing, processing environmental information and conversing with neighbouring sensors. These requisites pose a new and interesting challenge for the development of IEEE 802.15.4 together with routing protocol. In this work, 6LoWPAN Routing Protocol with Local Repair Using Bio Inspired Artificial Bee Colony (6RLR-ABC) has been introduced. This protocol supports connection establishment between nodes in an energy-efficient manner while maintaining high packet delivery ratio and throughput and minimizing average end-to-end delay. This protocol has been evaluated based on increasing generated traffic. The performance of the designed 6RLR-ABC routing protocol has been evaluated compared to 6LoWPAN Ad-hoc On-Demand Distance Vector (LOAD) routing protocol. LOAD protocol has been chosen since it is the most relevant existed 6LoWPANrouting protocol. The simulation results show that the introduced 6RLR-ABC protocol achieves lower packet average end-to-end delay and lower energy consumption compared to LOAD protocol.Additionally,the packet delivery ratio of the designed protocol is much higher than LOAD protocol. The proposed 6RLR-ABC achieved about 39% higher packet delivery ratio and about 54.8% higher throughput while simultaneously offering lower average end-to-end delay and lower average energy consumption than LOAD protocol.
description: 19 pages, 12 figures
PRODUCTION RISK AND INPUT USE: PASTORAL ZONE OF EASTERN AUSTRALIA
Creators: name: Anderson, Jock R.
name: Griffiths, William E.
name: Anderson, Jock R.
name: Griffiths, William E.
Publisher: name: Unknown
Year: 1981
Subjects: Productivity Analysis
Risk and Uncertainty

description: Few attempts have been made to estimate production functions for the Australian grazing industries. The question of the nature of the effect of input levels on production risk has been broached even more rarely. Previous investigators had to employ models and methods of estimation which embody highly restrictive implicit assumptions about the nature of risk effects. A typical restrictive feature has been the implication that increasing input intensity leads to increasing risk. In this paper, a much less restrictive model and corresponding estimation techniques are brought to bear on individual farm data for 38 properties with 10 continuous years of production records. Perhaps not surprisingly, it is found that some inputs (especially those capital inputs which might normally be thought of as increasing the safety of production) tend to reduce risk.
ESTIMATING THE IMPACT OF BEEF IMPORT RESTRICTIONS IN THE US IMPORT MARKET
Creators: name: Chambers, Robert G.
name: Just, Richard E.
name: Moffitt, L. Joe
name: Schmitz, Andrew
name: Chambers, Robert G.
name: Just, Richard E.
name: Moffitt, L. Joe
name: Schmitz, Andrew
Publisher: name: Unknown
Year: 1981
Subjects: subject: International Relations/Trade
subject: Marketing
subject: FOS: Economics and business

description: A beef import model is specified and estimated using disequilibrium econometrics. The statistical significance of the model suggests that disequilibrium has historically existed in the US beef import market. Surplus analysis based on the disequilibrium framework indicates that a welfare loss has been incurred as a result of the quota and associated voluntary restraint programmes that have existed in that market.
Strongly correlated Fermi-Bose mixtures in disordered optical lattices
Creators: name: Sanchez-Palencia, L.
name: Ahufinger, V.
name: Kantian, A.
name: Zakrzewski, Jakub
name: Sanpera, A.
name: Lewenstein, M.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: We investigate theoretically the low-temperature physics of a two-component ultracold mixture of bosons and fermions in disordered optical lattices. We focus on the strongly correlated regime. We show that, under specific conditions, composite fermions, made of one fermion plus one bosonic hole, form. The composite picture is used to derive an effective Hamiltonian whose parameters can be controlled via the boson-boson and the boson-fermion interactions, the tunneling terms and the inhomogeneities. We finally investigate the quantum phase diagram of the composite fermions and we show that it corresponds to the formation of Fermi glasses, spin glasses, and quantum percolation regimes.
description: Proceedings of the 3rd International Workshop on `Theory of Quantum Gases and Quantum Coherence'
Galling, Kurt (Hrsg.), Die Religion in Geschichte und Gegenwart (RGG)
Creators: name: Krüger
Publisher: name: Ökumenische Rundschau
Year: 2025

description: Ökumenische Rundschau, Bd. 13 Nr. 2 (1964): Ökumenische Rundschau, Band 13, Heft 2
Study on the escape timescale of high-energy particles from supernova remnants through thermal X-ray properties
Creators: name: Suzuki, Hiromasa
name: Bamba, Aya
name: Yamazaki, Ryo
name: Ohira, Yutaka
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: In this decade, GeV/TeV gamma-ray observations of several supernova remnants (SNRs) have implied that accelerated particles are escaping from their acceleration sites. However, when and how they escape from the SNR vicinities are yet to be understood. Recent studies have suggested that the particle escape might develop with thermal plasma ages of the SNRs. In this paper, we present a systematic study on time evolution of particle escape using thermal X-ray properties and gamma-ray spectra. We used 38 SNRs which associate with GeV/TeV gamma-ray emissions. We conducted spectral fittings on the gamma-ray spectra using exponential cutoff power law and broken power law models to estimate the exponential cutoff or the break energies, both of which are indicators of particle escape. The plots of the gamma-ray cutoff/break energies over the plasma ages show similar tendencies to those predicted by simple theories of the particle escape under conditions in which a shock is interacting with thin interstellar medium or clouds. The particle escape timescale is estimated as $\sim$100 kyr from decreasing trends of the total energy of the confined protons with the plasma age. The large dispersions of the cutoff/break energies of the data may suggest an intrinsic variety of particle escape environments. This might be the cause of the complicated Galactic cosmic-ray spectral shape measured on Earth.
description: 20 pages, 12 figures, accepted for PASJ
ASSESSING SOME EFFECTS OF INFLATION ON THE AGRICULTURAL SECTOR
Creators: name: Freebairn, John W.
name: Freebairn, John W.
Publisher: name: Unknown
Year: 1981
Subjects: Agricultural Finance
Demand and Price Analysis

description: The time pattern of effects of inflation on prices received, prices paid, asset returns, and real incomes of different members of the agricultural sector is described. In the long run it is argued that inflation will have very small, if any, effects on relative prices or real incomes. For the short run, which may be several years, it is likely that some prices will rise more slowly than others and cause income losses. Included in the group of losers are producers of export products.
On Hilberg's Law and Its Links with Guiraud's Law
Creators: name: Dȩbowski, Łukasz
Publisher: name: arXiv
Year: 2005
Subjects: subject: Computation and Language (cs.CL)
subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences

description: Hilberg (1990) supposed that finite-order excess entropy of a random human text is proportional to the square root of the text length. Assuming that Hilberg's hypothesis is true, we derive Guiraud's law, which states that the number of word types in a text is greater than proportional to the square root of the text length. Our derivation is based on some mathematical conjecture in coding theory and on several experiments suggesting that words can be defined approximately as the nonterminals of the shortest context-free grammar for the text. Such operational definition of words can be applied even to texts deprived of spaces, which do not allow for Mandelbrot's ``intermittent silence'' explanation of Zipf's and Guiraud's laws. In contrast to Mandelbrot's, our model assumes some probabilistic long-memory effects in human narration and might be capable of explaining Menzerath's law.
description: To appear in Journal of Quantitative Linguistics
RESOURCE POLICIES, PROPERTY RIGHTS AND CONFLICTS OF INTEREST
Creators: name: Izac, Anne-Marie N.
name: Izac, Anne-Marie N.
Publisher: name: Unknown
Year: 1986
Subjects: Land Economics/Use
Resource /Energy Economics and Policy

description: Chicagoan theories of and policies for unpriced natural resources have gathered momentum over the past twenty years and have reached a fair degree of acceptability among some agricultural economists and some governments. The critical evaluation of the logic, explanatory and predictive power of these theories, which is undertaken in this paper, shows that this acceptability is not well founded. It is demonstrated that these theories embody substantial logical shortcomings and rely on hypotheses which may be falsified. These limitations have important implications for Chicagoan resource policies. Game theory is used to show that Pareto optimality cannot be reached when Chicagoan policies are implemented by a government, contrary to the contention of Chicagoan economists.
Switzerland
Creators: name: Tunger-Zanetti, Andreas
Publisher: name: Zenodo
Year: 2019

description: kein Abstract vorhanden
description: + ID der Publikation: unilu_50415 + Titel der Reihe: Yearbook of Muslims in Europe + Sprache: Englisch + Letzte Aktualisierung: 2021-01-27 22:10:20
Intrinsic and extrinsic spin-orbit coupling and spin relaxation in monolayer PtSe$_2$
Creators: name: Kurpas, Marcin
name: Fabian, Jaroslv
Publisher: name: arXiv
Year: 2020
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Monolayer PtSe$_2$ is a semiconducting transition metal dichalcogenide characterized by an indirect band gap, space inversion symmetry, and high carrier mobility. Strong intrinsic spin-orbit coupling and the possibility to induce extrinsic spin-orbit fields by gating make PtSe$_2$ attractive for fundamental spin transport studies as well as for potential spintronics applications. We perform a systematic theoretical study of the spin-orbit coupling and spin relaxation in this material. Specifically, we employ first principles methods to obtain the basic orbital and spin-orbital properties of PtSe$_2$, also in the presence of an external transverse electric field. We calculate the spin mixing parameters $b^2$ and the spin-orbit fields $Ω$ for the Bloch states of electrons and holes. This information allows us to predict the spin lifetimes due to the Elliott-Yafet and D'yakonov-Perel mechanisms. We find that $b^2$ is rather large, on the order of $10^{-2}$ and $10^{-1}$, while $Ω$ varies strongly with doping, being about $10^{3} - 10^{4}$\,ns$^{-1}$ for %typical Fermi levels in the interval $(10-100)$ meV, carrier density in the interval $10^{13}-10^{14}$\,cm$^{-2}$ at the electric field of 1 V/nm. We estimate the spin lifetimes to be on the picosecond level.
NE2001p: A Native Python Implementation of the NE2001 Galactic Electron Density Model
Creators: name: Ocker, S. K.
name: Cordes, J. M.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The Galactic electron density model NE2001 describes the multicomponent ionized structure of the Milky Way interstellar medium. NE2001 forward models the dispersion and scattering of compact radio sources, including pulsars, fast radio bursts, AGNs, and masers, and the model is routinely used to predict the distances of radio sources lacking independent distance measures. Here we present the open-source package NE2001p, a fully Python implementation of NE2001. The model parameters are identical to NE2001 but the computational architecture is optimized for Python, yielding small (<1%) numerical differences between NE2001p and the Fortran code. NE2001p can be used on the command-line and through Python scripts available on PyPI. Future package releases will include modular extensions aimed at providing short-term improvements to model accuracy, including a modified thick disk scale height and additional clumps and voids. This implementation of NE2001 is a springboard to a next-generation Galactic electron density model now in development.
description: 3 pages, 1 figure, code available at https://pypi.org/project/mwprop/
Origin of Ferromagnetism and its pressure and doping dependence in Tl$_{2}$Mn$_{2}$O$_{7}$
Creators: name: Saha-Dasgupta, T.
name: De Raychaudhury, Molly
name: Sarma, D. D.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Using NMTO-{\it downfolding} technique, we explore and establish the origin of ferromagnetism in the pyrochlore system, Tl$_{2}$Mn$_{2}$O$_{7}$. It is found to be driven by hybridization induced spin-polarization of the delocalized charge carriers derived from Tl-$s$ and O-$p$ states. The mean-field estimate of the ferromagnetic transition temperature, T$_c$, estimated using computed exchange integrals are found to be in good agreement with the measurements. We find an enhancement of T$_{c}$ for moderate doping with nonmagnetic Sb and a suppression of T$_{c}$ upon application of pressure, both in agreement with experimental findings.
description: Accepted for publication in PRL
Photonic integrated quantum key distribution receiver for multiple users
Creators: name: Kong, Lingwen
name: Li, Zhihao
name: Li, Congxiu
name: Cao, Lin
name: Xing, Zeyu
name: Cao, Junqin
name: Wang, Yaxin
name: Cai, Xinlun
name: Zhou, Xiaoqi
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Integrated photonics has the advantages of miniaturization, low cost, and CMOS compatibility, and it provides a stable, highly integrated, and practical platform for quantum key distribution (QKD). While photonic integration of optical components has greatly reduced the overall cost of QKD systems, single-photon detectors (SPDs) have become the most expensive part of a practical QKD system. In order to circumvent this obstacle and make full use of SPDs, we have designed and fabricated a QKD receiver chip for multiple users. Our chip is based on a time-division multiplexing technique and makes use of a single set of SPDs to support up to four users' QKD. Our proof-of-principle chip-based QKD system is capable of producing an average secret key rate of 13.68 kbps for four users with a quantum bit error rate (QBER) as low as 0.51% over a simulated distance of 20 km in fiber. Our result clearly demonstrates the feasibility of multiplexing SPDs for setting QKD channels with different users using photonic integrated chip and may find applications in the commercialization of quantum communication technology.
On the quantum description of the early universe
Creators: name: Bengochea, Gabriel R.
Publisher: name: arXiv
Year: 2020
Subjects: subject: General Physics (physics.gen-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Why is it interesting to try to understand the origin of the universe? Everything we observe today, including our existence, arose from that event. Although we still do not have a theory that allows us to describe the origin itself, the study of the very early era of the universe involves the ideal terrain to analyze the interface between two of today's most successful physical theories, General Relativity and Quantum physics. But it is also an area in which we have a large number of observational data to test our theoretical ideas. Two of the fathers of Quantum physics, Niels Bohr and Werner Heisenberg, shared some thoughts that could be described with these words: "Quantum physics tells us that there is a line between the observed and the observer, and therefore science should be limited to what is observed. We must give up a complete, objective and realistic theory of the world". This article will orbit around these ideas and summarizes how it is that today, from recent works, we are in a position to try to challenge them (at least in part) through cosmology, seeking the quantum description of the early universe.
description: 9 pages
PLANT LOCATION ANALYSIS USING DISCRETE STOCHASTIC PROGRAMMING
Creators: name: Brown, Colin G.
name: Drynan, Ross G.
name: Brown, Colin G.
name: Drynan, Ross G.
Publisher: name: Unknown
Year: 1986
Subjects: Research Methods/ Statistical Methods

description: A plant location model with two major aspects is outlined. First, discrete stochastic programming is used to handle variability in supplies and demands. Second, the cost structure of plants is modelled in more detail and with more realism than is usual. Results from applying the model to the Queensland cattle slaughtering industry demonstrate the inappropriateness of using traditional deterministic plant location models to analyse problems with major stochastic elements. Deterministic models yield plant locations, sizes, throughputs, commodity flows and implications which differ markedly from those generated by stochastic models in which plant sizes and locations are optimally matched to variable fat cattle supplies. In addition, the traditional deterministic long-run model overestimates the normative gains of industry rationalisation.
Enhanced molecular spin-photon coupling at superconducting nanoconstrictions
Creators: name: Gimeno, I.
name: Kersten, W.
name: Pallarés, M. C.
name: Hermosilla, P.
name: Martínez-Pérez, M. J.
name: Jenkins, M. D.
name: Angerer, A.
name: Sánchez-Azqueta, C.
name: Zueco, D.
name: Majer, J.
name: Lostao, A.
name: Luis, F.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We combine top-down and bottom-up nanolithography to optimize the coupling of small molecular spin ensembles to $1.4$ GHz on-chip superconducting resonators. Nanoscopic constrictions, fabricated with a focused ion beam at the central transmission line, locally concentrate the microwave magnetic field. Drops of free-radical molecules have been deposited from solution onto the circuits. For the smallest ones, the molecules were delivered at the relevant circuit areas by means of an atomic force microscope. The number of spins $N_{\rm eff}$ effectively coupled to each device was accurately determined combining Scanning Electron and Atomic Force Microscopies. The collective spin-photon coupling constant has been determined for samples with $N_{\rm eff}$ ranging between $2 \times 10^{6}$ and $10^{12}$ spins, and for temperatures down to $44$ mK. The results show the well-known collective enhancement of the coupling proportional to the square root of $N_{\rm eff}$. The average coupling of individual spins is enhanced by more than four orders of magnitude (from $4$ mHz up to above $180$ Hz) when the transmission line width is reduced from $400$ microns down to $42$ nm, and reaches maximum values near $1$ kHz for molecules located on the smallest nanoconstrictions. This result opens promising avenues for the realization of magnetic spectroscopy experiments at the nanoscale and for the development of hybrid quantum computation architectures based on molecular spin qubits.
description: 31 pages, 6 figures, supporting information in ancillary PDF file
What hinders or facilitates successful crisis negotiation
Creators: name: Logan, Matthew H.
Publisher: name: University of British Columbia
Year: 2009

description: Referred to as "law enforcement's most effective non-lethal weapon," crisis negotiation is used successfully around the world but the elements that lead to success have been presented based on anecdote and impression. The present study attempts to analyze the critical incidents within law enforcement responses to barricaded subjects and suicidal persons and determine what facilitates or hinders success in crisis negotiation. Flanagan's (1954) Critical Incident Analysis methodology was used to investigate how police crisis negotiators "build bridges out of barricades." A total of 717 critical incidents were collected. Fourteen categories emerged from an inductive study of the incidents reported by the 22 participants. The results indicate that the following factors can contribute to either successor failure: Teamwork, active listening, relationship building, logistics, building a bridge, leadership, learning and development, using intuition, negotiator's personal resources, providing information and direction, support, and time. The results also indicate that success in crisis negotiation can be hindered by the subject's orientation and the subject's behaviour. These are elements that can clearly be influenced by the negotiator but are outside of his/her direct control. There was a strong emphasis on teamwork and the need to strive toward synchronizing the effort of command, tactical, and negotiation units to form a unified crisis response team. The dominance of this category seems to emanate from the continued presence of tension between these units and the desire of negotiators to present a unified presence so that a bridge can be built from chaos to a calm, safe environment.
Costs and Benefits of a WTO Dispute: Philippine Bananas and the Australian Market
Creators: name: Javelosa, Josyline C.
name: Schmitz, Andrew
name: Javelosa, Josyline C.
name: Schmitz, Andrew
Publisher: name: Unknown
Year: 2006
Subjects: subject: International Relations/Trade
subject: bananas
subject: cost-benefit analysis
subject: sanitary and phytosanitary (SPS) measures
subject: trade disputes
subject: World Trade Organization

description: Why do governments engage in WTO disputes? What can countries expect to gain from international legal trade battles? This article examines the costs and benefits of the Philippine-Australian dispute regarding Australia's quarantine policy on Philippine fresh fruits and vegetables, a case also of keen interest to a number of countries including those in the European Union, the United States, Canada, Ecuador, Thailand, China, India, and Chile. We find that a host of institutional, political, and economic factors can trigger disputes under strong, yet debatable, expectations over winning a case in the WTO.
Correlations for subsets of particles in symmetric states: what photons are doing within a beam of light when the rest are ignored
Creators: name: Goldberg, Aaron Z.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Quantum Physics (quant-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Given a state of light, how do its properties change when only some of the constituent photons are observed and the rest are neglected (traced out)? By developing formulae for mode-agnostic removal of photons from a beam, we show how the expectation value of any operator changes when only $q$ photons are inspected from a beam, ignoring the rest. We use this to reexpress expectation values of operators in terms of the state obtained by randomly selecting $q$ photons. Remarkably, this only equals the true expectation value for a unique value of $q$: expressing the operator as a monomial in normally ordered form, $q$ must be equal to the number of photons annihilated by the operator. A useful corollary is that the coefficients of any $q$-photon state chosen at random from an arbitrary state are exactly the $q$th order correlations of the original state; one can inspect the intensity moments to learn what any random photon will be doing and, conversely, one need only look at the $n$-photon subspace to discern what all of the $n$th order correlation functions are. The astute reader will be pleased to find no surprises here, only mathematical justification for intuition. Our results hold for any completely symmetric state of any type of particle with any combination of numbers of particles and can be used wherever bosonic correlations are found.
description: 11+3 pages, 1 figure, comments always welcome
Exchange instabilities in electron systems: Bloch versus Stoner Ferromagnetism
Creators: name: Zhang, Ying
name: Sarma, S. Das
Publisher: name: arXiv
Year: 2005
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We show that 2D and 3D electron systems with the long-range Coulomb electron-electron interaction could develop ferromagnetic instabilities due to strong exchange effects at low densities. The critical densities in both 2D and 3D systems at which the magnetic instability, which could either be of Stoner type (second-order) or of Bloch type (first-order), are higher than the dispersion instability critical density where effective mass at the Fermi surface diverges. We discuss the theoretical as well as experimental implications of the ferromagnetic instability at low electron densities, particularly in low-disorder semiconductor-based two-dimensional systems.
description: Revised version. Accepted for publication in PRB
Dynamics of Neutrino Wave Packet in the Tachyon-like Dirac Equation
Creators: name: Nanni, Luca
Publisher: name: arXiv
Year: 2020
Subjects: subject: General Physics (physics.gen-ph)
subject: FOS: Physical sciences

description: In this study the tachyon-like Dirac equation, formulated by Chodos to describe superluminal neutrino, is solved. The analytical solutions are Gaussian wave packets obtained using the envelope method. It is shown that the superluminal neutrino behaves like a pseudo-tachyon, namely a particle with subluminal velocity and pure imaginary mass that fulfils the energy-momentum relation typical of classical tachyons. The obtained results are used to prove that the trembling motion of the particle position around the median, known as Zitterbewegung, also takes place for the superluminal neutrino, even if the oscillation velocity is always lower than the speed of light. Finally, the pseudo-tachyon wave packet is used to calculate the probability of oscillation between mass states, obtaining a formula analogous to the one obtained for the ordinary neutrino. This suggest that in the experiments concerning neutrino oscillation is not possible to distinguish tachyonic neutrinos from ordinary ones.
description: 11 pages, 2 figures
Canadian Agriculture and the Doha Development Agenda: The Challenges
Creators: name: Rude, James
name: Meilke, Karl D.
name: Rude, James
name: Meilke, Karl D.
Publisher: name: Unknown
Year: 2006
Subjects: subject: International Relations/Trade
subject: Canadian agriculture
subject: Doha
subject: trade liberalization
subject: WTO

description: The WTO Framework Agreement that negotiators accepted in July 2004, and built upon at the 2005 Hong Kong Ministerial meeting provides a guide to the commitments a Doha Development Agenda agreement may contain. These commitments will relate to direct and indirect export subsidies, domestic support and market access. Commitments in each of these areas will have implications for Canadian agriculture. This article explores these implications for supply management, the Canadian Wheat Board and domestic support programs.
Generalized Group Actions in a Global Setting
Creators: name: Konjik, Sanja
name: Kunzinger, Michael
Publisher: name: arXiv
Year: 2005
Subjects: subject: Functional Analysis (math.FA)
subject: FOS: Mathematics
subject: 46T30; 35A30; 58E40

description: We study generalized group actions on differentiable manifolds in the Colombeau framework, extending previous work on flows of generalized vector fields and symmetry group analysis of generalized solutions. As an application, we analyze group invariant generalized functions in this setting.
Parton Distributions
Creators: name: Pumplin, Jon
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: I present an overview of some current topics in the measurement of Parton Distribution Functions.
description: 13 pages, 9 figures. Plenary talk presented at the XIII International Workshop on Deep Inelastic Scattering (DIS 2005), Madison WI USA, April 27--May 1, 2005
Deflating the Chinese Balloon: Types of Twitter Bots in US-China balloon incident
Creators: name: Ng, Lynnette Hui Xian
name: Carley, Kathleen M.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Social and Information Networks (cs.SI)
subject: FOS: Computer and information sciences

description: As digitalization increases, countries employ digital diplomacy, harnessing digital resources to project their desired image. Digital diplomacy also encompasses the interactivity of digital platforms, providing a trove of public opinion that diplomatic agents can collect. Social media bots actively participate in political events through influencing political communication and purporting coordinated narratives to influence human behavior. This article provides a methodology towards identifying three types of bots: General Bots, News Bots and Bridging Bots, then further identify these classes of bots on Twitter during a diplomatic incident involving the United States and China. Using a series of computational methods, this article examines the impact of bots on the topics disseminated, the influence and the use of information maneuvers of bots within the social communication network. Among others, our results observe that all three types of bots are present across the two countries; bots geotagged to the US are generally concerned with the balloon location while those geotagged to China discussed topics related to escalating tensions; and perform different extent of positive narrative and network information maneuvers.
WTO Constraints on U.S. and EU Domestic Support in Agriculture: The October 2005 Proposals: Technical Annex
Creators: name: Brink, Lars
name: Brink, Lars
Publisher: name: Unknown
Year: 2006
Subjects: International Relations/Trade

description: This document is the technical annex to the full paper "WTO Constraints on U.S. and EU Domestic Support in Agriculture: The October 2005 Proposals" which is available separately.
The effect of Zn substitution on the state of oxygen deficiency and hole concentration in Y1-xCaxBa2(Cu1-yZny)3O7-d
Creators: name: Naqib, S. H.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We have investigated the effect of Zn substitution on the hole content, p, and the oxygen deficiency, d, for a series of high-quality crystalline c-axis oriented thin films and polycrystalline Y1-xCaxBa2(Cu1-yZny)3O7-delta compounds over a wide range of composition (x, y, and delta). p was determined from the room-temperature thermopower, S[290K]. When annealed at a given temperature and oxygen partial pressure, a small but systematic variation in S[290K] was observed with Zn, for all the samples. From the analysis of the temperature derivative of resistivity, drho/dT, at 300K, which varies almost linearly with p, irrespective of the composition of the sample, and the thermo-gravimetric analysis (TGA), we have found that annealing under identical conditions makes the Zn-substituted compounds somewhat more oxygen deficient compared to the Zn-free ones.
$Spitzer$-selected $z > 1.3$ protocluster candidates in the LSST Deep Drilling Fields
Creators: name: Gully, Harry
name: Hatch, Nina
name: Bahé, Yannick
name: Balogh, Michael
name: Bolzonella, Micol
name: Cooper, M. C.
name: Muzzin, Adam
name: Pozzetti, Lucia
name: Rudnick, Gregory
name: Vulcani, Benedetta
name: Wilson, Gillian
Publisher: name: arXiv
Year: 2024
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We have identified 189 candidate $z > 1.3$ protoclusters and clusters in the LSST Deep Drilling Fields. This sample will enable the measurement of the metal enrichment and star formation history of clusters during their early assembly period through the direct measurement of the rate of supernovae identified through the LSST. The protocluster sample was selected from galaxy overdensities in a $Spitzer$/IRAC colour-selected sample using criteria that were optimised for protocluster purity using a realistic lightcone. Our tests reveal that $60-80\%$ of the identified candidates are likely to be genuine protoclusters or clusters, which is corroborated by a $\sim4σ$ stacked X-ray signal from these structures. We provide photometric redshift estimates for 47 candidates which exhibit strong peaks in the photo-$z$ distribution of their candidate members. However, the lack of a photo-$z$ peak does not mean a candidate is not genuine, since we find a stacked X-ray signal of similar significance from both the candidates that exhibit photo-$z$ peaks and those that do not. Tests on the lightcone reveal that our pursuit of a pure sample of protoclusters results in that sample being highly incomplete ($\sim4\%$) and heavily biased towards larger, richer, more massive, and more centrally concentrated protoclusters than the total protocluster population. Most ($\sim75\%$) of the selected protoclusters are likely to have a maximum collapsed halo mass of between $10^{13}-10^{14}$ M$_{\odot}$, with only $\sim25\%$ likely to be collapsed clusters above $10^{14}$ M$_{\odot}$. However, the aforementioned bias ensures our sample is $\sim50\%$ complete for structures that have already collapsed into clusters more massive than $10^{14}$ M$_{\odot}$.
description: 18 pages, 14 figures
On origami embeddings of flat tori
Creators: name: Tsuboi, Takashi
Publisher: name: arXiv
Year: 2020
Subjects: subject: Geometric Topology (math.GT)
subject: FOS: Mathematics
subject: 57Q35, 32G15, 32G10

description: We give explicit origami embeddings of a 2-dimensional flat torus of any modulus in the 3-dimensional Euclidean space.
description: 15 pages, 8 figures
Band structure and magnetotransport of a two-dimensional electron gas in the presence of spin-orbit interaction
Creators: name: Wang, X. F.
name: Vasilopoulos, P.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The band structure and magnetotransport of a two-dimensional electron gas (2DEG), in the presence of the Rashba (RSOI) and Dresselhaus (DSOI) terms of the spin-orbit interaction and of a perpendicular magnetic field, is investigated. Exact and approximate analytical expressions for the band structure are obtained and used to calculate the density of states (DOS) and the longitudinal magnetoresitivity assuming a Gaussian type of level broadening. The interplay between the Zeeman coupling and the two terms of the SOI is discussed. If the strengths $α$ and $ β$, of the RSOI and DSOI, respectively, are equal and the $g$ factor vanishes, the two spin states are degenerate and a shifted Landau-level structure appears. With the increase of the difference $α- β$, a novel beating pattern of the DOS and of the Shubnikov-de Haas (SdH) oscillations appears distinctly different from that occurring when one of these strengths vanishes.
Singularity confinement in delay-differential Painlevé equations
Creators: name: Stokes, Alexander
Publisher: name: arXiv
Year: 2020
Subjects: subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: 34K41 (Primary) 14E05, 39A36 (Secondary)

description: We study singularity confinement phenomena in examples of delay-differential Painlevé equations, which involve shifts and derivatives with respect to a single independent variable. We propose a geometric interpretation of our results in terms of mappings between jet spaces, defining certain singularities analogous to those of interest in the singularity analysis of discrete systems, and what it means for them to be confined. For three previously studied examples of delay-differential Painlevé equations, we describe all such singularities and show they are confined in the sense of our geometric description.
description: 31 pages, 2 figures
Density functional description of water condensation in proximity of nanoscale asperity
Creators: name: Paramonov, Pavel B.
name: Lyuksyutov, Sergei F.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: We apply non-local density functional formalism to describe an equilibrium distribution of the water-like fluid in the asymmetric nanoscale junction presenting an atomic force microscope (AFM) tip dwelling above an arbitrary surface. The hydrogen bonding dominating in intermolecular attraction is modeled as a square well potential with two adjustable parameters (energy and length) characterizing well's depth and width. A water meniscus formed inside nanoscale junction is explicitly described for different humidity. Furthermore, we suggest a simple approach using polymolecular adsorption isotherms for the evaluation of an energetic parameter characterizing fluid (water) attraction to substrate. This model can be easily generalized for more complex geometries and effective intermolecular potentials. Our study establishes a framework for the density functional description of fluid with orientational anisotropy induced by non-uniform external electric field.
The experience of becoming a clinical supervisor
Creators: name: Majcher, Jo-Ann Marie
Publisher: name: University of British Columbia
Year: 2009

description: This study explored the lived experiences of Counselling Psychology doctoral students as they underwent the transition from being a counsellor to undertaking the role of clinical supervisor. Phenomenology provided both the philosophical and methodological framework for addressing the research question: How do supervisors-in-training experience and make sense of the process of becoming a clinical supervisor? Six doctoral students enrolled in a clinical supervision course voluntarily participated in a series of three process interviews over the eight month duration of the course: one at the beginning of the course, one midway through and one at the end. A follow-up interview was also conducted with each participant to examine and validate common themes of meaning. Phenomenological themes that were common to all participants were uncovered in each interview set. These shared structures of meaning provided in rich detail the participating doctoral students experiences of becoming clinical supervisors, and how they made sense of their experiences. In addition to the common patterns of experiences that were discovered, a relationship dimension emerged that was shared by all participants, and ran through all themes in all sets of interviews. This study focused specifically on the growth and development of supervisors-in-training. The findings contribute to a greater understanding of the learning process involved in becoming a clinical supervisor. Results are compared to the available theoretical literature related to supervisor development. Implications for supervisor training and recommendations for future research are also discussed.
Enjoying a Good Port with a Clear Conscience: Geographic Indicators, Rent Seeking and Development
Creators: name: Kerr, William A.
name: Kerr, William A.
Publisher: name: Unknown
Year: 2006
Subjects: subject: International Relations/Trade
subject: developing countries
subject: geographic indicators
subject: incentives
subject: rent seeking
subject: sustainable development
subject: WTO

description: The European Union is attempting to have the protection of geographic indicators strengthened in the WTO. There may be sufficient rents and other benefits available to justify this strategy in the negotiations. To achieve its rent-seeking goals, however, the European Union needs allies at the negotiations. It has been courting developing countries by touting the benefits of geographic indicators for their products. For most products originating in developing countries, the opportunities for rents will first have to be created, a resource-intensive and problematic activity. Further, even if rents can be created in the short run, the forces of competition are likely to erode them. Scarce resources might be better utilized on other development strategies that are more likely to yield sustainable development.
National Policies and the Limits of International Integration
Creators: name: Gerber, James
name: Gerber, James
Publisher: name: Unknown
Year: 2000
Subjects: subject: International Relations/Trade
subject: deeper integration
subject: free trade
subject: Heckscher-Ohlin model
subject: integration
subject: trade barriers
subject: WTO

description: In spite of the rapid growth of merchandise trade since the end of World War II, the world economy is far from integrated. Services trade, capital flows, population migration, and price differences demonstrate far more scope for international economic integration. Even among nations with preferential trade agreements, networks of merchandise trade relations are far denser intra-nationally than internationally. The absence of goods trade predicted by trade models when nations have few policy barriers implies that crossing national boundaries is a significant indicator of increased transaction costs. These patterns have caused the world trade agenda to examine some unintended trade restrictions which make up a part of national domestic policies. This focus is apparent in current negotiations such as the Free Trade of the Americas Agreement. New items for negotiation include product standards, competition policies, services, and investment policies. Most contentious are labor and environmental standards, where the potential for protectionist capture is greater and the mutual recognition versus harmonization debate is obscured.
The Case For and Against Import Embargoes on Products of Biotechnology: Technical Annex
Creators: name: Gaisford, James D.
name: Chui-Ha, Carol Lau
name: Gaisford, James D.
name: Chui-Ha, Carol Lau
Publisher: name: Unknown
Year: 2000
Subjects: International Relations/Trade

description: This document is the technical annex to the full paper "The Case For and Against Import Embargoes on Products of Biotechnology", which is available separately.