cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Imaginary love stories related to substance use disorder: A case report.
Creators: name: SIDDIQUI, JAVED ATHER
name: QURESHI, SHAZIA FARHEEN
Publisher: name: figshare
Year: 2023
Subjects: classificationCode: 520302
subject: Clinical psychology

description: The substance crystal meth is methamphetamine, a stimulant and addictive substance that increases physical activity and wakefulness as well as producing other effects like fetishism and hallucinations. Here we report a patient with a manifestation of transvestic fetishistic behavior occurs after methamphetamine use. The comorbidity between fetishism and addiction has been demonstrated in several studies. According to research, symptoms of fetishism increase and decrease depending on the amount of crystal meth administered
Fully two-dimensional incommensurate charge modulation on the Pd-terminated polar surface of PdCoO2
Creators: name: Kong, Pengfei
name: Li, Guowei
name: Yang, Zhongzheng
name: Wen, Chenhaoping
name: Qi, Yanpeng
name: Felser, Claudia
name: Yan, Shichao
Publisher: name: arXiv
Year: 2021
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Here we use low-temperature scanning tunneling microscopy and spectroscopy to study the polar surfaces of PdCoO2. On the CoO2-terminated polar surface, we detect the quasiparticle interference pattern originating from the Rashba spin-split surface states. On the well-ordered Pd-terminated polar surface, we observe a regular lattice which has larger lattice constant than the atomic lattice of PdCoO2. In comparison with the shape of the hexagonal bulk Fermi surface, we identify this regular lattice as a fully two-dimensional incommensurate charge modulation that is driven by the Fermi surface nesting. More interestingly, we also find the moiré pattern induced by the interference between the two-dimensional incommensurate charge modulation in the Pd layer and the underlying CoO2 lattice. Our results not only show a new charge modulation on the Pd surface of PdCoO2, but also pave the way for fully understanding the novel electronic properties of this material.
description: 12 pages, 4 figures
A scalable DG solver for the electroneutral Nernst-Planck equations
Creators: name: Roy, Thomas
name: Andrej, Julian
name: Beck, Victor A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Numerical Analysis (math.NA)
subject: Applied Physics (physics.app-ph)
subject: Chemical Physics (physics.chem-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences
subject: G.1.8; G.1.3
subject: 65N30, 65F08, 78A57

description: The robust, scalable simulation of flowing electrochemical systems is increasingly important due to the synergy between intermittent renewable energy and electrochemical technologies such as energy storage and chemical manufacturing. The high Péclet regime of many such applications prevents the use of off-the-shelf discretization methods. In this work, we present a high-order Discontinuous Galerkin scheme for the electroneutral Nernst-Planck equations. The chosen charge conservation formulation allows for the specific treatment of the different physics: upwinding for advection and migration, and interior penalty for diffusion of ionic species as well the electric potential. Similarly, the formulation enables different treatments in the preconditioner: AMG for the potential blocks and ILU-based methods for the advection-dominated concentration blocks. We evaluate the convergence rate of the discretization scheme through numerical tests. Strong scaling results for two preconditioning approaches are shown for a large 3D flow-plate reactor example.
description: 26 pages, 7 figures
How a dissimilar-chain system is splitting. Quasi-static, subsonic and supersonic regimes
Creators: name: Berinskii, Igor E.
name: Slepyan, Leonid I.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Classical Physics (physics.class-ph)
subject: FOS: Physical sciences
subject: 74xx

description: We consider parallel splitting of a strip composed of two different chains. As a waveguide, the dissimilar-chain structure radically differs from the well-studied identical-chain system. It is characterized by three speeds of the long waves, two for the separate chains, and one for the intact strip where the chains are connected. Accordingly, there exist three ranges, the subsonic for both chains, the intersonic and the supersonic. The speed in the latter range is supersonic for the intact strip and at the same time, it is subsonic for the separate higher-speed chain. This fact allows the splitting wave to propagate in the strip supersonically. We derive steady-state analytical solutions and find that the splitting can propagate steadily only in two of these speed ranges, the subsonic and the supersonic, whereas the intersonic regime is forbidden. In the case of considerable difference in the chain stiffness, the lowest dynamic threshold corresponds to the supersonic regime. The peculiarity of the supersonic mode is that the supersonic energy delivery channel, being initially absent, is opening with the moving splitting point. Based on the discrete and related continuous models we find which regime can be implemented depending on the structure parameters and loading conditions. The analysis allows us to represent the characteristics of such processes and to demonstrate strengths and weaknesses of different formulations, quasi-static, dynamic, discrete or continuous. Analytical solutions for steady-state regimes are obtained and analyzed in detail. We find the force-speed relations and show the difference between the static and dynamic thresholds. The parameters and energy of waves radiated by the propagating splitting are determined. We calculate the strain distribution ahead of the transition point and check whether the steady-state solutions are admissible.
description: 23 pages, 15 figures
Accretion of rotating fluids onto stationary solutions
Creators: name: Azreg-Aïnou, Mustapha
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We consider a general stationary solution and derive the general laws for accretion of rotating perfect fluids. For non-degenerate and degenerate Fermi and Bose fluids we derive new effects that mimic the center-of-mass-energy effect of two colliding particle in the vicinity of horizons. Non-degenerate fluids see their chemical potential grow arbitrarily and ultra-relativistic Fermi fluids see their specific enthalpy and Fermi momentum grow arbitrarily too while the latter vanishes gradually for non-relativistic Fermi fluids. For degenerate Bose fluids two scenarios remain possible as the fluid approaches a horizon: a) The Bose-Einstein condensation ceases or b) the temperature drops gradually down to zero.
description: 11 pages, no figures, a few minor corrections. To appear in Phys. Rev. D
Intrinsic ferromagnetic and antiferromagnetic axion insulators in van der Waals materials Mn\emph{X}$_{2}$\emph{B}$_{2}$\emph{T}$_{6}$ family
Creators: name: Gao, Yan
name: Liu, Kai
name: Lu, Zhong-Yi
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The MnBi$_{2}$Te$_{4}$ family has attracted significant attention due to its rich topological states such as the quantum anomalous Hall (QAH) insulator state, the axion insulator state, and the magnetic Weyl semimetal state. Nevertheless, the intrinsic antiferromagnetic (AFM) interlayer coupling in MnBi$_{2}$Te$_{4}$ partly hinders the realization of "high-temperature" QAH effect. Here, by using first-principles electronic structure calculations, we design a new class of materials Mn\emph{X}$_{2}$\emph{B}$_{2}$\emph{T}$_{6}$ (\emph{X}=Ge, Sn, or Pb; \emph{B}=Sb or Bi; \emph{T}=Se or Te) based on the \emph{X}$_{2}$\emph{B}$_{2}$\emph{T}$_{5}$ structures rather than the Bi$_{2}$Te$_{3}$ family. We find that each septuple-layer Mn\emph{B}$_{2}$\emph{T}$_{4}$ is sandwiched by two [\emph{X}\emph{T}] layers, which may turn the AFM interlayer coupling into a ferromagnetic (FM) coupling. The calculations specifically demonstrate that \emph{MnGe}$_{2}$\emph{Sb}$_{2}$\emph{Te}$_{6}$, \emph{MnGe}$_{2}$\emph{Bi}$_{2}$\emph{Te}$_{6}$, and \emph{MnPb}$_{2}$\emph{Bi}$_{2}$\emph{Te}$_{6}$ are FM axion insulators, while MnGe$_{2}$Sb$_{2}$Se$_{6}$, MnGe$_{2}$Bi$_{2}$Se$_{6}$, MnSn$_{2}$Sb$_{2}$Te$_{6}$, and MnSn$_{2}$Bi$_{2}$Te$_{6}$ are A-type AFM axion insulators. These seven materials all have an out-of-plane easy axis of magnetization. The Mn\emph{X}$_{2}$\emph{B}$_{2}$\emph{T}$_{6}$ family thus offers a promising platform beyond the MnBi$_{2}$Te$_{4}$ family for the realization of quantized magnetoelectric effect and "high-temperature" QAH effect in future experiments.
description: 6 pages, 4 figures, 1 table
Tailoring High-Frequency Magnonics in Monolayer Chromium Trihalides
Creators: name: Menezes, Raí M.
name: Šabani, Denis
name: Bacaksiz, Cihan
name: Silva, Clécio C. de Souza
name: Milošević, Milorad V.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Monolayer chromium trihalides, the archetypal two dimensional (2D) magnetic materials, are readily suggested as a promising platform for high frequency magnonics. Here we detail the spin wave properties of monolayer CrBr$_3$ and CrI$_3$, using spin dynamics simulations parametrized from the first principles. We reveal that spin wave dispersion can be tuned in a broad range of frequencies by strain, paving the way towards flexo magnonic applications. We further show that ever present halide vacancies in these monolayers host sufficiently strong Dzyaloshinskii Moriya interaction to scatter spin waves, which promotes design of spin-wave guides by defect engineering. Finally we discuss the spectra of spin-waves propagating across a moiré periodic modulation of magnetic parameters in a van der Waals heterobilayer, and show that the nanoscale moiré periodicities in such samples are ideal for realization of a magnonic crystal in the terahertz frequency range. Recalling the additional tunability of magnetic 2D materials by electronic gating, our results situate these systems among the front-runners for prospective high frequency magnonic applications.
Long-lived Bell states in an array of optical clock qubits
Creators: name: Schine, Nathan
name: Young, Aaron W.
name: Eckner, William J.
name: Martin, Michael J.
name: Kaufman, Adam M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: Quantum Gases (cond-mat.quant-gas)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The generation of long-lived entanglement on an optical clock transition is a key requirement to unlocking the promise of quantum metrology. Arrays of neutral atoms constitute a capable quantum platform for accessing such physics, where Rydberg-based interactions may generate entanglement between individually controlled and resolved atoms. To this end, we leverage the programmable state preparation afforded by optical tweezers along with the efficient strong confinement of a 3d optical lattice to prepare an ensemble of strontium atom pairs in their motional ground state. We engineer global single-qubit gates on the optical clock transition and two-qubit entangling gates via adiabatic Rydberg dressing, enabling the generation of Bell states, $|ψ\rangle = \frac{1}{\sqrt{2}}\left(|gg\rangle + i|ee\rangle \right)$, with a fidelity of $\mathcal{F}= 92.8(2.0)$%. For use in quantum metrology, it is furthermore critical that the resulting entanglement be long lived; we find that the coherence of the Bell state has a lifetime of $τ_{bc} = 4.2(6)$ s via parity correlations and simultaneous comparisons between entangled and unentangled ensembles. Such Bell states can be useful for enhancing metrological stability and bandwidth. Further rearrangement of hundreds of atoms into arbitrary configurations using optical tweezers will enable implementation of many-qubit gates and cluster state generation, as well as explorations of the transverse field Ising model and Hubbard models with entangled or finite-range-interacting tunnellers.
QUIC Throughput and Fairness over Dual Connectivity
Creators: name: Hasselquist, David
name: Lindström, Christoffer
name: Korzhitskii, Nikita
name: Carlsson, Niklas
name: Gurtov, Andrei
Publisher: name: arXiv
Year: 2021
Subjects: subject: Networking and Internet Architecture (cs.NI)
subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: Performance (cs.PF)
subject: FOS: Computer and information sciences
subject: C.2.2; C.4; C.2
subject: 68M12, 68M14, 68M20, 68M10

description: Dual Connectivity (DC) is an important lower-layer feature accelerating the transition from 4G to 5G that also is expected to play an important role in standalone 5G radio networks. However, even though the packet reordering introduced by DC can significantly impact the performance of upper-layer protocols, no prior work has studied the impact of DC on QUIC. In this paper, we present the first such performance study. Using a series of throughput and fairness experiments, we show how QUIC is affected by different DC parameters, network conditions, and whether the DC implementation aims to improve throughput or reliability. Results for two QUIC implementations (aioquic, ngtcp2) and two congestion control algorithms (NewReno, CUBIC) are presented under both static and highly time-varying network conditions. Our findings provide network operators with insights and understanding into the impacts of splitting QUIC traffic in a DC environment. With reasonably selected DC parameters and increased UDP receive buffers, QUIC over DC performs similarly to TCP over DC and achieves optimal fairness under symmetric link conditions when DC is not used for packet duplication. The insights can help network operators provide modern users with better end-to-end service when deploying DC.
description: 14 pages. This paper is published in Computer Networks (by Elsevier)
Low-energy Spin Dynamics of Quantum Spin Liquid Candidate $NaYbSe_{2}$
Creators: name: Zhang, Zheng
name: Li, Jianshu
name: Xie, Mingtai
name: Zhuo, Weizhen
name: Adroja, D. T.
name: Baker, Peter J.
name: Perring, T. G.
name: Zhang, Anmin
name: Jin, Feng
name: Ji, Jianting
name: Wang, Xiaoqun
name: Ma, Jie
name: Zhang, Qingming
Publisher: name: arXiv
Year: 2021
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The family of rare earth chalcogenides $ARECh_{2}$ (A = alkali or monovalent ions, RE = rare earth, and Ch = O, S, Se, and Te) appears as an inspiring playground for studying quantum spin liquids (QSL). The crucial low-energy spin dynamics remain to be uncovered. By employing muon spin relaxation ($μ$SR) and zero-field (ZF) AC susceptibility down to 50 mK, we are able to identify the gapless QSL in $NaYbSe_{2}$, a representative member with an effective spin-1/2, and explore its unusual spin dynamics. The ZF $μ$SR experiments unambiguously rule out spin ordering or freezing in $NaYbSe_{2}$ down to 50 mK, two orders of magnitude smaller than the exchange coupling energies. The spin relaxation rate, $λ$, approaches a constant below 0.3 K, indicating finite spin excitations featured by a gapless QSL ground state. This is consistently supported by our AC susceptibility measurements. The careful analysis of the longitudinal field (LF) $μ$SR spectra reveals a strong spatial correlation and a temporal correlation in the spin-disordered ground state, highlighting the unique feature of spin entanglement in the QSL state. The observations allow us to establish an experimental H-T phase diagram. The study offers insight into the rich and exotic magnetism of the rare earth family.
description: 21 pages, 18 figures
Temperature driven spin-zero effect in TaAs$_2$
Creators: name: Alam, Md Shahin
name: Tanwar, P. K.
name: Dybko, Krzysztof
name: Wadge, Ashutosh S.
name: Iwanowski, Przemyslaw
name: Wisniewski, Andrzej
name: Matusiak, Marcin
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The electrical and thermo-electrical transport effects of the TaAs$_2$ semimetal were measured in a magnetic field applied along [-2 0 1] direction. The resulting field dependences of the resistivity as well as the Hall, Seebeck and Nernst coefficient below T ~ 100 K can be satisfactory described within the two-band model consisting of the electron and hole pockets. At low temperature all the measured effects exhibit significant contribution from quantum oscillations. The fast Fourier transform (FFT) of the oscillatory Nernst signal shows two fundamental frequencies, Fa = 105 T and Fb = 221 T, and the second harmonic of the latter (F2b = 442 T). The ratio between FFT amplitudes of Fb and F2b changes with temperature in an unusual way, indicating that we observe the spin-zero effect caused by temperature change. This is likely related to substantial temperature dependence of the Lande g-factor, which in turn can result from non-parabolic energy dispersion or temperature evolution of the spin-orbit coupling.
description: 30 pages, 14 figures
Gravitational shock wave inside a steadily-accreting spherical charged black hole
Creators: name: Eilon, Ehud
Publisher: name: arXiv
Year: 2016
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We numerically investigate the interior of a four-dimensional, spherically symmetric charged black hole accreting neutral null fluid. Previous study by Marolf and Ori suggested that late infalling observers encounter an effective shock wave as they approach the outgoing portion of the inner horizon. Non-linear perturbations could generate an effective gravitational shock wave, which manifests as a drop of the area coordinate $r$ from inner horizon value $r_{-}$ towards zero in an extremely short proper time duration of the infalling observer. We consider three different scenarios: a) A charged black hole accreting a single (ingoing) null fluid; b) a charged black hole perturbed by two null fluids, ingoing and outgoing; c) a charged black hole perturbed by an ingoing null fluid and a self-gravitating scalar field. While we do not observe any evidence for a gravitational shock in the first case, we detect the shock in the other two, using ingoing timelike and null geodesics. The shock width $Δτ$ decreases rapidly with a fairly good match to a new, generalized exponential law, $Δτ\sim e^{-\intopκ_{-} (\widetilde{V}_{f})d\widetilde{V}_{f}}$, where $\widetilde{V}_{f}$ is a specific timing parameter for the ingoing timelike geodesics and $κ_{-}(\widetilde{V}_{f})$ is a generalized (Reissner-Nordström like) surface gravity of the charged black hole at the inner horizon. We also gain new insight into the inner (classical) structure of a charged black hole perturbed by two null fluids, including strong evidence for the existence of a spacelike $r=0$ singularity. We use a finite-difference numerical code with double-null coordinates combined with an adaptive gauge method in order to solve the field equations from the region outside the black hole down to the vicinity of the $r=0$ singularity.
description: - 42 pages, 18 figures. - Changes in text (most notably, abstract and Introduction), additional references. - Version accepted for publication in Physical Review D (8/2/2017)
Optimized Two-Baryon Operators in Lattice QCD
Creators: name: Lyu, Yan
name: Tong, Hui
name: Sugiura, Takuya
name: Aoki, Sinya
name: Doi, Takumi
name: Hatsuda, Tetsuo
name: Meng, Jie
name: Miyamoto, Takaya
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: A set of optimized interpolating operators which are dominantly coupled to each eigenstate of two baryons on the lattice is constructed by the HAL QCD method. To test its validity, we consider heavy dibaryons $Ω_{3Q}Ω_{3Q}$ ($Q=s,c$) calculated by (2+1)-flavor lattice QCD simulations with nearly physical pion mass. The optimized two-baryon operators are shown to provide effective energies of the ground and excited states separately stable as a function of the Euclidean time. Also they agree to the eigenenergies in a finite lattice box obtained from the leading-order HAL QCD potential $V({\boldsymbol{r}})$ within statistical errors. The overlapping factors between the optimized sink operators and the state created by the wall-type source operator indicate that $V( \boldsymbol{r})$ can be reliably extracted, no matter whether the spacetime correlation of two baryons is dominated by the ground state or the excited state. It is suggested that the optimized set of operators is useful for variational studies of hadron-hadron interactions.
description: Accepted for publication in Physical Review D (8 pages, 7 figures)
Asymptotic expansion for the solution of a convection-diffusion problem in a thin graph-like junction
Creators: name: Mel'nyk, Taras A.
name: Klevtsovskiy, Arsen V.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 76R99, 35J25, 35B40, 35B25, 74K30

description: A steady-state convection-diffusion problem with a small diffusion of order $\mathcal{O}(\varepsilon)$ is considered in a thin three-dimensional graph-like junction consisting of thin cylinders connected through a domain (node) of diameter $\mathcal{O}(\varepsilon),$ where $\varepsilon$ is a small parameter. Using multiscale analysis, the asymptotic expansion for the solution is constructed and justified. The asymptotic estimates in the norm of Sobolev space $H^1$ as well as in the uniform norm are proved for the difference between the solution and proposed approximations with a predetermined accuracy with respect to the degree of $\varepsilon$.
description: 22 pages, 3 figures
Enantiodiscrimination of chiral molecules via quantum correlation function
Creators: name: Zou, Fen
name: Chen, Yu-Yuan
name: Liu, Bo
name: Li, Yong
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We propose a method to realize enantiodiscrimination of chiral molecules based on quantum correlation function in a driven cavity-molecule system, where the chiral molecule is coupled with a quantized cavity field and two classical light fields to form a cyclic three-level model. According to the inherent properties of electric-dipole transition moments of chiral molecules, there is a $π$-phase difference in the overall phase of the cyclic three-level model for the left- and right-handed chiral molecules. Thus, the correlation function depends on this overall phase and is chirality-dependent. The analytical and numerical results indicate that the left- and right-handed chiral molecules can be discriminated by detecting quantum correlation function. Our work opens up a promising route to discriminate molecular chirality, which is an extremely important task in pharmacology and biochemistry.
description: 13 pages, 5 figures
Development of foraging strategies in bees
Creators: name: Dubois, Thibault
Publisher: name: Macquarie University
Year: 2022
Subjects: Other education not elsewhere classified

description: Effective foraging for food is such a necessity for most animals it is reasonable to expect natural selection to favour individuals that optimise their nutrient intake and minimise energy expenditure. One way to achieve these goals is through the use of specific behaviours, called “foraging strategies”. Pollinators such as bees present a very interesting case of foraging optimisation. Since the nectar offered by plants is a renewable resource bees have a strong incentive to learn and memorise the positions of the flowers they have discovered. Many studies have investigated the foraging behaviour of bees, leading to the identification of two foraging strategies: the use of stable, repeated routes between subsets of flowers (“traplines”) and the development of areas of exclusion of other bees in competitive situations (“resource partitioning”). The use of these two strategies by bees has been demonstrated multiple times in different situations, but we still know very little about how such strategies develop. These two strategies have mostly been described through cognitively complex mechanisms. However, while they have been observed and characterised in controlled environments, these strategies were seldom seen in more natural environments, suggesting our current explanations of these phenomena are incomplete. This gap in knowledge leads me to question what are the behavioural rules individual bees follow to establish these strategies? My thesis focused on attempting to gain some insight on how these foraging strategies form by complementing experiments with a modelling approach. I built an agent-based model of multiple bees foraging in a wide variety of environments. With it I tried to explain the establishment of these strategies through the use of simple positive and negative reinforcement rules as bees found flowers with or without rewards, respectively. Exploration of the model showed that both traplining and partitioning strategies could emerge in simple competitive situations with two bees foraging on 10 feeding sites. I then conducted three experiments to challenge the assumptions of the model. My results suggest that the foraging strategies of bees could emerge from simple foraging rules, but more importantly that their development in natural conditions could be mostly driven from the spatial and temporal constraints of the environment which are altering the availability in resources. Bees were able to improve their foraging efficiency in most experimental conditions, but how they did so was not limited to the establishment of traplines or resource partitioning. By explaining their formation mostly through these constraints, we are able to present these foraging strategies not as cognitively intensive processes, but rather paths of least resistance to environmental constraints.
Flavour anomalies in supersymmetric scenarios with non-minimal flavour violation
Creators: name: Boussejra, M. A.
name: Mahmoudi, F.
name: Uhlrich, G.
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Motivated by tensions between experimental measurements and SM predictions in $b\to s \ell^+\ell^-$ transitions, we present the first study of non-minimal flavour-violating Minimal Supersymmetric Standard Model (MSSM) scenarios contributing to the relevant Wilson coefficients to address the observed anomalies using SuperIso and MARTY. We calculate the full one-loop analytical contributions of the general MSSM to Wilson coefficients relevant for flavour anomalies, together with the anomalous muon magnetic dipole moment $(g-2)_μ$. We show that, after imposing theoretical constraints on the flavour-violating parameters we can find scenarios in agreement with the experimental measurements that can address at the same time the tensions in flavour observables and in $(g-2)_μ$.
description: 34 pages, 12 figures, 5 tables. v2: references added
Hierarchical Multiscale Modelling of CoCu Catalyst in CO Hydrogenation : Bridge the Gap between Microscopic and Mesoscopic Systems
Creators: name: Zha, Shenjun
Publisher: name: Karlsruher Institut für Technologie (KIT)
Year: 2022

description: Die heterogene Katalyse stellt einen Grundpfeiler der modernen Gesellschaft dar und deckt nach und nach den Bedarf an chemischen Lösungen. Die Geschichte der Katalyse begann bereits im neunzehnten Jahrhundert und hat sich fortlaufend weiterentwickelt. Daraus entstanden unter anderem die Ammoniaksynthese, das katalytisches Cracking, die Polymerisation und die Abgaskatalyse. All diese Entdeckungen stützen sich auf theoretischem Hintergrundwissen und Trial-and Error-Experimenten. Eine der aufregendsten Veränderungen in der theoretischen Chemie ist die Entwicklung der Rechenverfahren. Mit der dramatisch entwickelten Computerhardware in den letzten zwei Jahrzehnten ermöglichen sie heute die Berechnung und damit die quantitative Interpretation spezifischer katalytischen Systemen. Rechenverfahren in der Katalyse, die Brücke zwischen Theorie und Experiment, zeigen ähnliche Trends wie experimentelle Untersuchungen. Anstelle von idealisierten Katalysatoroberflächen und Reaktionsbedingungen stellet die rechnerische Perspektive eher „operando“-Informationen bereit. Infolgedessen wurden viele neue Techniken entwickelt, z. B. globale Optimierungstechniken, mikrokinetische Simulationen, auf maschinellem Lernen basierende Methoden und ab initio Thermodynamik. In dieser Arbeit haben wir die CoCu-Katalysatoren für CO Hydrierung untersucht. Als erstes konnten große CoCu-Partikel zunächst mit Hilfe von auf maschinellem Lernen basierendem Monte Carlo-Methode ohne Kompromisse in der Genauigkeit untersucht werden und die Co@Cu-Kern-Schale Struktur direkt bestätigt werden. Zweitens wurde das Zusammenspiel von Zwischenprodukten mit den CoCu-Oberflächen über globale Optimierung quantifiziert. Basierend auf der Trennungsrichtung unterschiedlicher Zwischenprodukte wurde ein schnelles Vorhersageschema für die Segregationspräferenz vorgeschlagen. Danach wurden die zwei vollständig entmischten Cu/Co(111) und Co/Cu(111) Oberflächen, die bei Beginn und Ende der Reaktion bestehen, untersucht. Die Ergebnisse weisen auf einen einzigen Typ aktiven Zentrums mit geeigneter CO Adsorption für die Bildung von $C_2$-Oxygenaten hin. Drittens, durch die Verwendung von ab initio Thermodynamik, deuten die Phasendiagramme auf eine teilweise entmischte CoCu-Oberfläche mit hoher CO-Bedeckung während der Reaktion hin. Zudem waren die erhaltenen kinetischen Ergebnisse sowohl aus der Mean-Field-Theorie als auch aus der Monte-Carlo-Methode Simulationen quantitativ konsistent.
Exponential size scaling of the Liouvillian gap in boundary-dissipated systems with Anderson localization
Creators: name: Zhou, Bozhen
name: Wang, Xueliang
name: Chen, Shu
Publisher: name: arXiv
Year: 2022
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: We carry out a systematical study of the size scaling of Liouvillian gap in boundary-dissipated one-dimensional quasiperiodic and disorder systems. By treating the boundary-dissipation operators as a perturbation, we derive an analytical expression of the Liouvillian gap, which indicates clearly the Liouvillian gap being proportional to the minimum of boundary densities of eigenstates of the underlying Hamiltonian, and thus give a theoretical explanation why the Liouvillian gap has different size scaling relation in the extended and localized phase. While the Liouvillian gap displays a power-law size scaling $Δ_{g}\propto L^{- 3}$ in the extended phase, our analytical result unveils that the Liouvillian gap fulfills an exponential scaling relation $Δ_{g}\propto e^{- κL}$ in the localized phase, where $κ$ takes the largest Lyapunov exponent of localized eigenstates of the underlying Hamiltonian. By scrutinizing the extended Aubry-André-Harper model, we numerically confirm that the Liouvillian gap fulfills the exponential scaling relation and the fitting exponent $κ$ coincides pretty well with the analytical result of Lyapunov exponent. The exponential scaling relation is further verified numerically in other one-dimensional quasiperiodic and random disorder models. We also study the relaxation dynamics and show the inverse of Liouvillian gap giving a reasonable timescale of asymptotic convergence to the steady state.
description: 11 pages, 4 figures
Spin partners of the $Z_b(10610)$ and $Z_b(10650)$ revisited
Creators: name: Baru, V.
name: Epelbaum, E.
name: Filin, A. A.
name: Hanhart, C.
name: Nefediev, A. V.
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We study the implications of the heavy-quark spin symmetry for the possible spin partners of the exotic states $Z_b(10610)$ and $Z_b(10650)$ in the spectrum of bottomonium. We formulate and solve numerically the coupled-channel equations for the $Z_b$ states that allow for a dynamical generation of these states as hadronic molecules. The force includes short-range contact terms and the one-pion exchange potential, both treated fully nonperturbatively. The strength of the potential at leading order is fixed completely by the pole positions of the $Z_b$ states such that the mass and the most prominent contributions to the width of the isovector heavy-quark spin partner states $W_{bJ}$ with the quantum numbers $J^{++}$ ($J=0,1,2$) come out as predictions. Since the accuracy of the present experimental data does not allow one to fix the pole positions of the $Z_b$'s reliably enough, we also study the pole trajectories of their spin partner states as functions of the $Z_b$ binding energies. It is shown that, once the heavy-quark spin symmetry is broken by means of the physical $B$ and $B^*$ masses, especially the pion tensor force has a significant impact on the location of the partner states clearly demonstrating the need of a coupled-channel treatment of pion dynamics to understand the spin multiplet pattern of hadronic molecules.
description: 21 pages, 5 figures, 1 table
Maximum Force for Black Holes and Buchdahl Stars
Creators: name: Dadhich, Naresh
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Black hole and Buchdahl star are identified respectively by $Φ(R)=1/2, 4/9$ where $g_{tt}=1-2Φ(R)$ for a spherically symmetric static metric. We investigate the maximum force for black hole and Buchdahl star when one of the participating objects is charged and/or rotating while the other is neutral and non-rotating. It turns out that the maximum force between two Schwarzschild objects is universal, given in terms of the fundamental constant velocity of light and the gravitational constant in general relativity (GR) in the usual four dimensional spacetime. In general this feature uniquely picks out the pure Lovelock gravity (having only one $N$th order term in action which includes GR in the linear order $N=1$) and the dimensional spectrum, $D=3N+1$, where $N$ is degree of the Lovelock polynomial action.
description: 5 pages, Abstract is revamped, some references are added and the CAS grant his acknowledged. No change in the results. Accepted for publication in PRD
Unveiling the Universe with Emerging Cosmological Probes
Creators: name: Moresco, Michele
name: Amati, Lorenzo
name: Amendola, Luca
name: Birrer, Simon
name: Blakeslee, John P.
name: Cantiello, Michele
name: Cimatti, Andrea
name: Darling, Jeremy
name: Della Valle, Massimo
name: Fishbach, Maya
name: Grillo, Claudio
name: Hamaus, Nico
name: Holz, Daniel
name: Izzo, Luca
name: Jimenez, Raul
name: Lusso, Elisabeta
name: Meneghetti, Massimo
name: Piedipalumbo, Ester
name: Pisani, Alice
name: Pourtsidou, Alkistis
name: Pozzetti, Lucia
name: Quartin, Miguel
name: Risaliti, Guido
name: Rosati, Piero
name: Verde, Licia
Publisher: name: arXiv
Year: 2022
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: The detection of the accelerated expansion of the Universe has been one of the major breakthroughs in modern cosmology. Several cosmological probes (CMB, SNe Ia, BAO) have been studied in depth to better understand the nature of the mechanism driving this acceleration, and they are being currently pushed to their limits, obtaining remarkable constraints that allowed us to shape the standard cosmological model. In parallel to that, however, the percent precision achieved has recently revealed apparent tensions between measurements obtained from different methods. These are either indicating some unaccounted systematic effects, or are pointing toward new physics. Following the development of CMB, SNe, and BAO cosmology, it is critical to extend our selection of cosmological probes. Novel probes can be exploited to validate results, control or mitigate systematic effects, and, most importantly, to increase the accuracy and robustness of our results. This review is meant to provide a state-of-art benchmark of the latest advances in emerging beyond-standard cosmological probes. We present how several different methods can become a key resource for observational cosmology. In particular, we review cosmic chronometers, quasars, gamma-ray bursts, standard sirens, lensing time-delay with galaxies and clusters, cosmic voids, neutral hydrogen intensity mapping, surface brightness fluctuations, stellar ages of the oldest objects, secular redshift drift, and clustering of standard candles. The review describes the method, systematics, and results of each probe in a homogeneous way, giving the reader a clear picture of the available innovative methods that have been introduced in recent years and how to apply them. The review also discusses the potential synergies and complementarities between the various probes, exploring how they will contribute to the future of modern cosmology.
description: Invited review article for Living Reviews in Relativity. Accepted version. 191 pages, 54 figures, 11 tables
Quantum Expectation Transformers for Cost Analysis
Creators: name: Avanzini, Martin
name: Moser, Georg
name: Péchoux, Romain
name: Perdrix, Simon
name: Zamdzhiev, Vladimir
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Logic in Computer Science (cs.LO)
subject: Programming Languages (cs.PL)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: We introduce a new kind of expectation transformer for a mixed classical-quantum programming language. Our semantic approach relies on a new notion of a cost structure, which we introduce and which can be seen as a specialisation of the Kegelspitzen of Keimel and Plotkin. We show that our weakest precondition analysis is both sound and adequate with respect to the operational semantics of the language. Using the induced expectation transformer, we provide formal analysis methods for the expected cost analysis and expected value analysis of classical-quantum programs. We illustrate the usefulness of our techniques by computing the expected cost of several well-known quantum algorithms and protocols, such as coin tossing, repeat until success, entangled state preparation, and quantum walks.
On Two Families of Generalizations of Pascal's Triangle
Creators: name: Allen, Michael A.
name: Edwards, Kenneth
Publisher: name: arXiv
Year: 2022
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 11B39 (Primary) 05A19, 05A15 (Secondary)

description: We consider two families of Pascal-like triangles that have all ones on the left side and ones separated by $m-1$ zeros on the right side. The $m=1$ cases are Pascal's triangle and the two families also coincide when $m=2$. Members of the first family obey Pascal's recurrence everywhere inside the triangle. We show that the $m$-th triangle can also be obtained by reversing the elements up to and including the main diagonal in each row of the $(1/(1-x^m),x/(1-x))$ Riordan array. Properties of this family of triangles can be obtained quickly as a result. The $(n,k)$-th entry in the $m$-th member of the second family of triangles is the number of tilings of an $(n+k)\times1$ board that use $k$ $(1,m-1)$-fences and $n-k$ unit squares. A $(1,g)$-fence is composed of two unit square sub-tiles separated by a gap of width $g$. We show that the entries in the antidiagonals of these triangles are coefficients of products of powers of two consecutive Fibonacci polynomials and give a bijective proof that these coefficients give the number of $k$-subsets of $\{1,2,\ldots,n-m\}$ such that no two elements of a subset differ by $m$. Other properties of the second family of triangles are also obtained via a combinatorial approach. Finally, we give necessary and sufficient conditions for any Pascal-like triangle (or its row-reversed version) derived from tiling $(n\times1)$-boards to be a Riordan array.
description: 20 pages, 6 figures
Leptoquarks with Exactly Stable Protons
Creators: name: Davighi, Joe
name: Greljo, Admir
name: Thomsen, Anders Eller
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We explore a novel mechanism to restrict TeV-scale leptoquark interactions and render the proton exactly stable to all orders in the effective field theory expansion. A scalar condensate breaks a lepton-flavoured $\mathrm{U}(1)_X$ gauge symmetry in the ultraviolet and generates neutrino masses, leaving a discrete $\mathbb{Z}_9$ or $\mathbb{Z}_{18}$ gauge symmetry in the infrared, forbidding $ΔB = 1$ processes. This provides an elegant framework to address the flavour anomalies and can be adapted to many other new-physics models. The $ \mathrm{U}(1)_X $ can emerge from a gauge-flavour unified $ \mathrm{SU}(12) \times \mathrm{SU}(2) \times \mathrm{SU}(2) $ theory at even higher energies.
description: 9 pages, 1 figure, 2 tables. v2: published version
On the Fundamental Limits of Random Non-orthogonal Multiple Access in Cellular Massive IoT
Creators: name: Shirvanimoghaddam, Mahyar
name: Condoluci, Massimo
name: Dohler, Mischa
name: Johnson, Sarah
Publisher: name: arXiv
Year: 2017
Subjects: subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences

description: Machine-to-machine (M2M) constitutes the communication paradigm at the basis of Internet of Things (IoT) vision. M2M solutions allow billions of multi-role devices to communicate with each other or with the underlying data transport infrastructure without, or with minimal, human intervention. Current solutions for wireless transmissions originally designed for human-based applications thus require a substantial shift to cope with the capacity issues in managing a huge amount of M2M devices. In this paper, we consider the multiple access techniques as promising solutions to support a large number of devices in cellular systems with limited radio resources. We focus on non-orthogonal multiple access (NOMA) where, with the aim to increase the channel efficiency, the devices share the same radio resources for their data transmission. This has been shown to provide optimal throughput from an information theoretic point of view.We consider a realistic system model and characterise the system performance in terms of throughput and energy efficiency in a NOMA scenario with a random packet arrival model, where we also derive the stability condition for the system to guarantee the performance.
description: To appear in IEEE JSAC Special Issue on Non-Orthogonal Multiple Access for 5G Systems
Impact of Side Chain Hydrophilicity on Packing, Swelling and Ion Interactions in Oxy-bithiophene Semiconductors
Creators: name: Siemons, Nicholas
name: Pearce, Drew
name: Cendra, Camila
name: Yu, Hang
name: Tuladhar, Sachetan M.
name: Hallani, Rawad K.
name: Sheelamanthula, Rajendar
name: LeCroy, Garrett S.
name: Siemons, Lucas
name: White, Andrew J. P.
name: Mcculloch, Iain
name: Salleo, Alberto
name: Frost, Jarvist M.
name: Giovannitti, Alexander
name: Nelson, Jenny
Publisher: name: arXiv
Year: 2022
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: Exchanging hydrophobic alkyl-based side chains to hydrophilic glycol-based side chains is a widely adopted method for improving mixed-transport device performance, despite the impact on solid state packing and polymer-electrolyte interactions being poorly understood. Presented here is a Molecular Dynamics (MD) force field for modelling alkoxylated and glycolated polythiophenes. The force field is validated against known packing motifs for their monomer crystals. MD simulations, coupled with X-ray Diffraction (XRD), show that alkoxylated polythiophenes will pack with a `tilted stack' and straight interdigitating side chains, whilst their glycolated counterpart will pack with a `deflected stack' and an s-bend side chain configuration. MD simulations reveal water penetration pathways into the alkoxylated and glycolated crystals - through the π-stack and through the lamellar stack respectively. Finally, the two distinct ways tri-ethylene glycol polymers can bind to cations are revealed, showing the formation of a meta-stable single bound state, or an energetically deep double bound state, both with a strong side chain length dependance. The minimum energy pathways for the formation of the chelates are identified, showing the physical process through which cations can bind to one or two side chains of a glycolated polythiophene, with consequences for ion transport in bithiophene semiconductors.
description: 10 pages, 4 figures
Towards Classification of $\mathcal{N}=1$ and $\mathcal{N}=0$ Flipped $SU(5)$ Asymmetric $\mathbb{Z}_2 \times \mathbb{Z}_2$ Heterotic String Orbifolds
Creators: name: Faraggi, Alon E.
name: Matyas, Viktor G.
name: Percival, Benjamin
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The free fermionic classification method provides a powerful tool to investigate string vacua, which led to the discovery of spinor--vector duality and exophobic string models. We extend the classification methodology to both $\mathcal{N}=1$ and $\mathcal{N}=0$ Flipped $SU(5)$ $\mathbb{Z}_2 \times \mathbb{Z}_2$ heterotic string orbifolds with asymmetric shifts. The impact of the asymmetric assignments on the phenomenological characteristics of these models is investigated. Of particular interest is the analysis of untwisted moduli fixing for various choices of asymmetric boundary conditions. Two classes of vacua with different characteristics are systematically investigated with help from SAT/SMT algorithms, which are shown to increase search efficiency by up to two orders of magnitude, as well as providing useful tools to find contradictions between various phenomenological criteria. The general form of the partition function for the space of models is explained and given for two specific example models for different choices of asymmetric boundary conditions. Additionally, the distribution of one-loop cosmological constant contributions for samples in the two different classes of models are depicted and discussed.
description: 50 pages, 8 figures
Modular operads as modules over the Brauer properad
Creators: name: Stoll, Robin
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Algebra (math.QA)
subject: Algebraic Topology (math.AT)
subject: Category Theory (math.CT)
subject: FOS: Mathematics
subject: 18M85 (Primary) 18M70 (Secondary)

description: We show that modular operads are equivalent to modules over a certain simple properad which we call the Brauer properad. Furthermore, we show that, in this setting, the Feynman transform corresponds to the cobar construction for modules of this kind. To make this precise, we extend the machinery of the bar and cobar constructions relative to a twisting morphism to modules over a general properad. This generalizes the classical case of algebras over an operad and might be of independent interest. As an application, we sketch a Koszul duality theory for modular operads.
description: 70 pages. Published version. Comments still welcome!