cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
On the theory of body motion in confined Stokesian fluids
Creators: name: Procopio, Giuseppe
name: Giona, Massimiliano
Publisher: name: arXiv
Year: 2023
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: We propose a theoretical method to decompose the solution of a Stokes flow past a body immersed in a confined fluid in two simpler problems, related separately to the two geometrical elements of these systems: (i) the body immersed in the unbounded fluid (represented by its Faxén operators), and (ii) the domain of the confinement (represented by its Stokesian multipoles). Specifically, by using a reflection method, and assuming linear and reciprocal boundary conditions \citep{procopio-giona_pof}, we provide the expression for the velocity field, the forces, torques and higher-order moments acting on the body in terms of: (i) the volume moments of the body in the unbounded ambient flow; (ii) the multipoles in the domain of the confinement; (iii) the collection of all the volumetric moments on the body immersed in all the regular parts of the multipoles considered as ambient flows. A detailed convergence analysis of the reflection method is developed. In the light of practical applications, we estimate the truncation error committed by considering only the lower order moments (thus truncating the matrices) and the errors associated with the approximated expressions available in the literature for force and torques. We apply the theoretical results to the archetypal hydrodynamic system of a sphere with Navier-slip boundary conditions near a plane wall with no-slip boundary conditions, to determine forces and torques on a translating and rotating sphere as a function of the slip length and of the distance of the sphere from the plane. The hydromechanics of a spheroid is also addressed.
A stabilizer code model with non-invertible symmetries: Strange fractons, confinement, and non-commutative and non-Abelian fusion rules
Creators: name: Kibe, Tanay
name: Mukhopadhyay, Ayan
name: Padmanabhan, Pramod
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We introduce a stabilizer code model with a qutrit at every edge on a square lattice and with non-invertible plaquette operators. The degeneracy of the ground state is topological as in the toric code, and it also has the usual deconfined excitations consisting of pairs of electric and magnetic charges. However, there are novel types of confined fractonic excitations composed of a cluster of adjacent faces with vanishing flux. They manifest confinement, and even larger configurations of these fractons are fully immobile although they acquire emergent internal degrees of freedom. Deconfined excitations change their nature in presence of these fractonic defects. As for instance, fractonic defects can absorb magnetic charges making magnetic monopoles exist while electric charges acquire restricted mobility. Furthermore, some generalized symmetries can annihilate any ground state and also the full sector of fully mobile excitations. All these properties can be captured via a novel type of \textit{non-commutative} and \textit{non-Abelian} fusion category in which the product is associative but does not commute, and can be expressed as a sum of (operator) equivalence classes. Generalized non-invertible symmetries give rise to the feature that the fusion products form a non-unital category without a proper identity. We show that a variant of this model features a deconfined fracton liquid phase and a phase where the dual (magnetic) strings have condensed.
description: 56 pages, 17 figures; v2: more clarifications about the properties of symmetry transformations added; v3: expanded discussion section; v4: one figure added and further discussion about symmetries included
Density engineering via inter-condensate dipole-dipole interactions
Creators: name: Nayak, Pranay
name: Ghosh, Ratheejit
name: Nath, Rejish
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Pattern Formation and Solitons (nlin.PS)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We study the effect of inter-condensate dipole-dipole interactions in a setup consisting of physically disconnected, single-species dipolar Bose-Einstein condensates. In particular, making use of the long-range and anisotropic nature of dipole-dipole interactions, we show that the density of a {\em target} dipolar Bose-Einstein condensate can be axially confined and engineered using a trapped {\em control} dipolar condensate. Increasing the number of control condensates leads to exotic ground state structures, including periodic patterns in the target condensate. The latter leads to a structural transition between single and double-peaked structures with coherence between the peaks controlled via the separation between the control condensates.
description: 9 pages, 8 figures
ОЦЕНКА СОСТОЯНИЯ УРОВНЯ НАТРИЙУРЕТИЧЕСКОГО ПЕПТИДА ПРИ ОСТРОМ КОРОНАРНОМ СИНДРОМЕ  И ПРИ НАРУШЕНИИ  МОЗГОВОГО КРОВООБРАЩЕНИЯ
Creators: name: Маджидова, Гульбахор
name: Суннатова, Гульбахор
name: Некбаева, Озода
name: Хидиров, Ильхом
Publisher: name: Zenodo
Year: 2024

description: изучение содержания натрийуретического пептида (NT-proBNP) у больных с острым коронарным синдромом (ОКС) в зависимости от наличия и выраженности сердечной недостаточности, по-прежнему актуально.
Equivariant covering type and the number of vertices in equivariant triangulations
Creators: name: Govc, Dejan
name: Marzantowicz, Waclaw
name: Pavesic, Petar
Publisher: name: arXiv
Year: 2023
Subjects: subject: Algebraic Topology (math.AT)
subject: FOS: Mathematics
subject: 55M30, 57Q15, 57R05

description: We introduce the notion of the \emph{equivariant covering type} of a space $X$ on which a finite group $G$ acts, and study its properties. The equivariant covering type measures the size of $G$-equivariant good covers of $X$ and is thus an extension of the \emph{covering type} of a space, introduced by Karoubi and Weibel. We show that the equivariant covering type is a $G$-homotopy invariant and describe its relation with other $G$-invariants, like the equivariant LS-category, $G$-genus and the multiplicative structures of equivariant cohomology theories. We also compute the $G$-covering type of regular $G$-graphs, give estimates for orientation-preserving actions on surfaces and for the projectivizations of complex representations of $G$ and cohomology spheres. As an application, we derive estimates of sizes of minimal $G$-triangulations for various $G$-spaces.
description: Revised version with a new title
1-arcsecond imaging of ELAIS-N1 field at 144MHz using the LoTSS survey with international LOFAR telescope
Creators: name: Ye, Haoyang
name: Sweijen, Frits
name: van Weeren, Reinout
name: Williams, Wendy
name: de Jong, Jurjen
name: Morabito, Leah K.
name: Rottgering, Huub
name: Shimwell, T. W.
name: Best, P. N.
name: Bondi, Marco
name: Brüggen, Marcus
name: de Gasperin, Francesco
name: Tasse, C.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: We present the first wide area (2.5 x 2.5 deg^2) LOFAR High Band Antenna image at a resolution of 1.2'' x 2'' with a median noise of approximately 80 microJy per beam. It was made from an 8-hour International LOFAR Telescope (ILT) observation of the ELAIS-N1 field at frequencies ranging from 120 to 168 MHz with the most up-to-date ILT imaging methods. This intermediate resolution falls between the highest possible resolution (0.3'') achievable by using all International LOFAR Telescope (ILT) baselines and the standard 6-arcsecond resolution in the LoTSS (LOFAR Two-meter Sky Survey) image products utilising the LOFAR Dutch baselines only. This is the first demonstration of the feasibility of imaging using the ILT at a resolution of around 1'', which provides unique information on source morphology at scales that fall below the surface brightness limits at higher resolutions. The total calibration and imaging computational time is approximately 52,000 core hours, nearly 5 times more than required to produce a 6'' resolution image. We also present a radio source catalogue containing 2263 sources detected over the 2.5 x 2.5 deg^2 image of the ELAIS-N1 field, with a peak intensity threshold of 5.5 sigma. The catalogue has been cross-matched with the LoTSS deep ELAIS-N1 field radio catalogue, and its flux density and positional accuracy have been investigated and corrected accordingly. We find that approximately 80% of sources which we expect to be detectable based on their peak brightness in the LoTSS 6'' resolution image are detected in this image, which is approximately a factor of two higher than for 0.3'' resolution imaging in the Lockman Hole, implying there is a wealth of information on these intermediate scales.
description: 20 pages, 19 figures, revised manuscript submitted to A&A
Mito e imaginário na obra de Ailton Krenak
Creators: name: Silva, Míriam
name: DRAVET, Florence
Publisher: name: Zenodo
Year: 2024

description: Resumo

Por meio do estudo da obra de Ailton Krenak, o objetivo deste artigo é de identificar no texto do escritor e filósofo indígena os elementos que podem compor sua visão de mito e as funções que este ocupa na vida indígena. Constatou-se a preferência do filósofo pelo termo "narrativa da tradição" e verificou-se a centralidade que esse conjunto de narrativas ocupa na preservação da identidade indígena. Vinculada às noções de natureza e ancestralidade, a narrativa da tradição indígena se vivencia no corpo, em sonhos, danças e cantos e alimenta o imaginário criador de novas narrativas. Conclui-se que o mito vivido pela cultura indígena e apresentado pelo filósofo é a expressão da complexidade da rede de relações da própria natureza de que o humano é parte.

Palavras-chave: Mito; Povo indígena; Natureza.
Ailton Krenak, pessoa-poesia
Creators: name: Silva, Míriam
name: DRAVET, Florence
Publisher: name: Zenodo
Year: 2024

description: Resumo

Nos últimos anos, a voz de Ailton Krenak se faz ouvir na mídia e na literatura, culminando com sua entrada na Academia Brasileira de Letras. Objetiva-se aqui fazer uma leitura do movimento entre mundos de Krenak a partir do conceito de pessoa-poesia. Nossa metodologia é antropofágica: uma leitura crítica e compreensiva de sua obra na relação com outros referenciais. Foi feito um movimento dialógico ao pensar a pessoa-poesia a partir da filosofia de Krenak e, ao mesmo tempo, a expressão de sua filosofia e ação política. Conclui-se que a poesia em Krenak é uma condição ontológica, a própria vida que se manifesta no corpo, na palavra e na ação política e lhe permite desenvolver sua performance.

Palavras chave: Ailton Krenak; Poesia; Ativismo político; Performance.
Efficient cycles of hyperbolic manifolds
Creators: name: Frigerio, Roberto
name: Grammatica, Ennio
name: Martelli, Bruno
Publisher: name: arXiv
Year: 2023
Subjects: subject: Geometric Topology (math.GT)
subject: FOS: Mathematics

description: Let $N$ be a complete finite-volume hyperbolic $n$-manifold. An efficient cycle for $N$ is the limit (in an appropriate measure space) of a sequence of fundamental cycles whose $\ell^1$-norm converges to the simplicial volume of $N$. Gromov and Thurston's smearing construction exhibits an explicit efficient cycle, and Jungreis and Kuessner proved that, in dimension $n\geq 3$, such cycle actually is the unique efficient cycle for a huge class of finite volume hyperbolic manifolds, including all the closed ones. In this paper we prove that, for $n\geq 3$, the class of finite-volume hyperbolic manifolds for which the uniqueness of the efficient cycle does not hold is exactly the commensurability class of the figure-8 knot complement (or, equivalently, of the Gieseking manifold).
description: 24 pages, 5 figures
Geometry of tropical extensions of hyperfields
Creators: name: Maxwell, James
name: Smith, Ben
Publisher: name: arXiv
Year: 2023
Subjects: subject: Algebraic Geometry (math.AG)
subject: Rings and Algebras (math.RA)
subject: FOS: Mathematics
subject: 12K99, 14T10 (Primary) 12J25, 12D10 (Secondary)

description: We study the geometry of tropical extensions of hyperfields, including the ordinary, signed and complex tropical hyperfields. We introduce the framework of 'enriched valuations' as hyperfield homomorphisms to tropical extensions, and show that a notable family of them are relatively algebraically closed. Our main results are hyperfield analogues of Kapranov's theorem and the Fundamental theorem of tropical geometry. Utilising these theorems, we introduce fine tropical varieties and prove a structure theorem for them in terms of their initial ideals.
description: Structure theorem for fine tropical varieties added (Thm 5.2), along with numerous expositional improvements. To appear in Proceedings A of the Royal Society of Edinburgh
Superconductivity induced by strong electron-exciton coupling in doped atomically thin semiconductor heterostructures
Creators: name: von Milczewski, Jonas
name: Chen, Xin
name: Imamoglu, Atac
name: Schmidt, Richard
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Gases (cond-mat.quant-gas)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We study a mechanism to induce superconductivity in atomically thin semiconductors where excitons mediate an effective attraction between electrons. Our model includes interaction effects beyond the paradigm of phonon-mediated superconductivity and connects to the well-established limits of Bose and Fermi polarons. By accounting for the strong-coupling physics of trions, we find that the effective electron-exciton interaction develops a strong frequency and momentum dependence accompanied by the system undergoing an emerging BCS-BEC crossover from weakly bound $s$-wave Cooper pairs to a superfluid of bipolarons. Even at strong-coupling the bipolarons remain relatively light, resulting in critical temperatures of up to 10\% of the Fermi temperature. This renders heterostructures of two-dimensional materials a promising candidate to realize superconductivity at high critical temperatures set by electron doping and trion binding energies.
description: 9+9 pages, 4+5 figures
The homology of moduli spaces of 4-manifolds may be infinitely generated
Creators: name: Konno, Hokuto
Publisher: name: arXiv
Year: 2023
Subjects: subject: Geometric Topology (math.GT)
subject: Algebraic Topology (math.AT)
subject: Differential Geometry (math.DG)
subject: FOS: Mathematics

description: For a simply-connected closed manifold $X$ of $\dim X \neq 4$, the mapping class group $π_0(\mathrm{Diff}(X))$ is known to be finitely generated. We prove that analogous finite generation fails in dimension 4. Namely, we show that there exist simply-connected closed smooth 4-manifolds whose mapping class groups are not finitely generated. More generally, for each $k>0$, we prove that there are simply-connected closed smooth 4-manifolds $X$ for which $H_k(B\mathrm{Diff}(X);\mathbb{Z})$ are not finitely generated. The infinitely generated subgroup of $H_k(B\mathrm{Diff}(X);\mathbb{Z})$ which we detect are topologically trivial, and unstable under the connected sum of $S^2 \times S^2$. The proof uses characteristic classes obtained from Seiberg-Witten theory.
description: 19 pages, minor revisions, to appear in Forum Math. Pi
Constraints on the accretion properties of quasi-periodic erupters from GRMHD simulations
Creators: name: Chashkina, Anna
name: Bromberg, Omer
name: Levinson, Amir
name: Nakar, Ehud
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Context: Some apparently quiescent supermassive black holes (BHs) at centers of galaxies show quasi-periodic eruptions (QPEs) in the X-ray band, the nature of which is still unknown. A possible origin for the eruptions is an accretion disk, however the properties of such disks are restricted by the timescales of reccurance and durations of the flares. Aims: In this work we test the possibility that the known QPEs can be explained by accretion from a compact accretion disk with an outer radius $r_{\rm out}\sim 10-40 r_{\rm g}$, focusing on a particular object GSN 069. Methods: We run several 3D GRMHD simulations with the {\tt HARMPI} code of thin and thick disks and study how the initial disk parameters such as thickness, magnetic field configuration, magnetization and Kerr parameter affect the observational properties of QPEs. Results: We show that accretion onto a slowly rotating BH through a small, thick accretion disk with an initially low plasma $β$ can explain the observed flare duration, the time between outbursts and the lack of evidence for a variable jet emission. In order to form such a disk the accreting matter should have a low net angular momentum. A potential source for such low angular momentum matter with a quasi periodic feeding mechanism might be a tight binary of wind launching stars.
description: Submitted to Astronomy and Astrophysics
Quantum Griffiths singularity in a three-dimensional superconductor to Anderson critical insulator transition
Creators: name: Qi, Shichao
name: Liu, Yi
name: Wang, Ziqiao
name: Chen, Fucong
name: Li, Qian
name: Ji, Haoran
name: Li, Rao
name: Li, Yanan
name: Fang, Jingchao
name: Liu, Haiwen
name: Wang, Fa
name: Jin, Kui
name: Xie, X. C.
name: Wang, Jian
Publisher: name: arXiv
Year: 2023
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Disorder is ubiquitous in real materials and can have dramatic effects on quantum phase transitions. Originating from the disorder enhanced quantum fluctuation, quantum Griffiths singularity (QGS) has been revealed as a universal phenomenon in quantum criticality of low-dimensional superconductors. However, due to the weak fluctuation effect, QGS is very challenging to detect experimentally in three-dimensional (3D) superconducting systems. Here we report the discovery of QGS associated with the quantum phase transition from 3D superconductor to Anderson critical insulator in a spinel oxide MgTi2O4 (MTO). Under both perpendicular and parallel magnetic field, the dynamical critical exponent diverges when approaching the quantum critical point, demonstrating the existence of 3D QGS. Among 3D superconductors, MTO shows a relatively strong fluctuation effect featured as a wide superconducting transition region. The enhanced fluctuation, which may arise from the mobility edge of Anderson localization, finally leads to the occurrence of 3D quantum phase transition and QGS. Our findings offer a new perspective to understand quantum phase transitions in strongly disordered 3D systems.
Measurement of the Hoyle State Radiative Transition Width
Creators: name: Rana, T. K.
name: Pandit, Deepak
name: Manna, S.
name: Kundu, S.
name: Banerjee, K.
name: Sen, A.
name: Pandey, R.
name: Mukherjee, G.
name: Ghosh, T. K.
name: Nayak, S. S.
name: Shil, R.
name: Karmakar, P.
name: Atreya, K.
name: Rani, K.
name: Paul, D.
name: Santra, Rajkumar
name: Sultana, A.
name: Basu, S.
name: Pal, S.
name: Sadhukhan, S.
name: Mondal, Debasish
name: Mukhopadhyay, S.
name: Bhattacharya, Srijit
name: Pal, Surajit
name: Pant, Pankaj
name: Roy, Pratap
name: Ali, Sk M.
name: Mondal, S.
name: De, A.
name: Dey, Balaram
name: Datta, R.
name: Bhattacharya, S.
name: Bhattacharya, C.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: The radiative decay of the Hoyle state is the doorway to the production of heavier elements in stellar environment. Here we report, an exclusive measurement of electric quadruple (E$_2$) transitions of the Hoyle state to the ground state of $^{12}$C through the $^{12}$C(p, p$^\prime$$γ$$γ$)$^{12}$C reaction. Triple coincidence measurement yields a value of radiative branching ratio $Γ_{rad}$/$Γ$ = 4.01 (30) $\times$ 10$^{-4}$. The result has been corroborated by an independent experiment based on the complete kinematical measurement $via.$ $^{12}$C(p, p$^\prime$)$^{12}$C reaction ($Γ_{rad}$/$Γ$ = 4.04 (30) $\times$ 10$^{-4}$). Using our results together with the currently adopted values of $Γ_π$(E$_0$)/$Γ$ and $Γ_π$($E_0$), the radiative width of the Hoyle state is found to be 3.75 (40) $\times$ 10$^{-3}$ eV. We emphasize here that our result is not in agreement with 34 $\%$ increase in the radiative decay width of the Hoyle state measured recently but consistent with the currently adopted value.
description: 7 pages, 5 figures
A thorough investigation of the prospects of eLISA in addressing the Hubble tension: Fisher Forecast, MCMC and Machine Learning
Creators: name: Shah, Rahul
name: Bhaumik, Arko
name: Mukherjee, Purba
name: Pal, Supratik
Publisher: name: arXiv
Year: 2023
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We carry out an in-depth analysis of the capability of the upcoming space-based gravitational wave mission eLISA in addressing the Hubble tension, with a primary focus on observations at intermediate redshifts ($3
description: To appear in JCAP, 30 pages, 12 sets of figures, 7 tables
Approximation theorems throughout Reverse Mathematics
Creators: name: Sanders, Sam
Publisher: name: arXiv
Year: 2023
Subjects: subject: Logic (math.LO)
subject: FOS: Mathematics
subject: 03B30, 03F35

description: Reverse Mathematics (RM for short) is a program in the foundations of mathematics where the aim is to find the minimal axioms needed to prove a given theorem of ordinary mathematics. Generally, the minimal axioms are equivalent to the theorem at hand, assuming a weak logical system called the base theory. Moreover, many (most?) theorems are either provable in the base theory or equivalent to one of four logical systems, together called the Big Five. For instance, the Weierstrass approximation theorem, i.e. that a continuous function can be approximated uniformly by a sequence of polynomials, has been classified in RM as being equivalent to weak Koenig's lemma, the second Big Five system. In this paper, we study approximation theorems for discontinuous functions via Bernstein polynomials from the literature. We obtain (many) equivalences between the latter and weak Koenig's lemma. We also show that slight variations of these approximation theorems fall far outside of the Big Five but fit in the recently developed RM of new 'big' systems, namely the uncountability of R, the enumeration principle for countable sets, the pigeon-hole principle for measure, and the Baire category theorem. In conclusion, one equivalence in second-order RM, namely for the Weierstrass approximation theorem, gives rise to many equivalences in higher-order RM, and we hope the case study in this paper can serve as a kind of template.
description: 25 pages. Same Appendix as arXiv:2303.00493. To appear in Journal of Symbolic Logic
Electron irradiation reveals robust fully gapped superconductivity in LaNiGa$_{2}$
Creators: name: Ghimire, S.
name: Joshi, K. R.
name: Krenkel, E. H.
name: Tanatar, M. A.
name: Shi, Yunshu
name: Konczykowski, M.
name: Grasset, R.
name: Taufour, V.
name: Orth, P. P.
name: Scheurer, M. S.
name: Prozorov, R.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: The effects of 2.5 MeV electron irradiation were studied in the superconducting phase of single crystals of LaNiGa$_2$, using measurements of electrical transport and radio-frequency magnetic susceptibility. The London penetration depth is found to vary exponentially with temperature, suggesting a fully gapped Fermi surface. The inferred superfluid density is close to that of a single-gap weak-coupling isotropic $s-$wave superconductor. Superconductivity is extremely robust against nonmagnetic point-like disorder induced by electron irradiation. Our results place strong constraints on the previously proposed triplet pairing state by requiring fine-tuned impurity scattering amplitudes and are most naturally explained by a sign-preserving, weak-coupling, and approximately momentum independent singlet superconducting state in LaNiGa$_2$, which does not break time-reversal symmetry. We discuss how our findings could be reconciled with previous measurements indicating magnetic moments in the superconducting phase.
An upper limit on the spins of merging binary black holes formed through binary evolution
Creators: name: Marchant, Pablo
name: Podsiadlowski, Philipp
name: Mandel, Ilya
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: As gravitational wave detectors improve, observations of black hole (BH) mergers will provide the joint distribution of their masses and spins. This will be a critical benchmark to validate formation scenarios. Merging binary BHs formed through isolated binary evolution require both components to be stripped of their hydrogen envelopes before core-collapse. The rotation rates of such stripped stars are constrained by their surface critical rotation, restricting their angular momentum content at core-collapse. We use stripped star models at low metallicities ($Z_\odot/10$, $Z_\odot/50$ and $Z_\odot/250$) to determine the spins of BHs produced by critically rotating stellar progenitors. To study how such progenitors can arise, we consider their formation through chemically homogeneous evolution (CHE). We use a semianalytical model to study the final spins of CHE binaries, and compare our results against available detailed population synthesis models. We find that above BH masses of $\simeq 25M_\odot$, the dimensionless spin of critically rotating stripped stars ($a = Jc/(GM^2$)) is below unity. This results in an exclusion region at high chirp masses and effective spins that cannot be populated by binary evolution. CHE can produce binaries where both BHs hit this limit, producing a pile-up at the boundary of the excluded region. Highly spinning BHs arise from very low-metallicity CHE systems with short delay times, which merge at higher redshifts. On the other hand, the contribution of CHE to merging binary BHs in the third observing run of the LVK collaboration is expected to be dominated by systems with low spins ($χ_\mathrm{eff}<0.5$) which merge near redshift zero. Owing to its higher projected sensitivity and runtime, the fourth observing run of the LVK collaboration can potentially place constraints on the high spin population and the existence of a limit set by critical rotation.
description: Submitted to A&A. Abstract abridged
Acoustic lattice instabilities at the magneto-structural transition in Fe$_{1.057(7)}$Te
Creators: name: Guratinder, K.
name: Chan, E.
name: Rodriguez, E. E.
name: Rodriguez-Rivera, J. A.
name: Stuhr, U.
name: Stunault, A.
name: Travers, R.
name: Green, M. A.
name: Qureshi, N.
name: Stock, C.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Fe$_{1.057(7)}$Te undergoes a first-order tetragonal to monoclinc structural transition at T$_{S} \sim 70$ K, breaking the C$_{4}$ lattice symmetry and simultaneously breaking time reversal symmetry with bicollinear magnetic order. We investigate the soft acoustic lattice dynamics near this combined magneto-structural transition. We apply spherically neutron polarimetry to study the static magnetism near this transition, characterized with x-ray powder diffraction, and find no evidence of static incommensurate magnetic correlations near the onset of monoclinic and bicollinear antiferromagnetic order. This fixes the position of our single crystal sample in the Fe$_{1+x}$Te phase diagram in the magnetic bicollinear region and illustrates that our sample statically undergoes a transition from a paramagnetic phase to a low-temperature bicollinear phase. We then apply neutron spectroscopy to study the acoustic phonons, related to elastic deformations of the lattice. We find a temperature dependent soft acoustic branch for phonons propagating along [010] and polarized along [100]. The slope of this acoustic phonon branch is sensitive to the elastic constant $C_{66}$ and the shear modulus. The temperature dependence of this branch displays a softening with a minimum near the magneto-structural transition of T$_{S}$ $\sim$ 70 K and a recovery within the magnetically ordered low temperature phase. Soft acoustic instabilities are present in the collinear phases of the chalcogenides Fe$_{1+x}$Te where nematic order found in Fe$_{1+δ}$Se is absent. We speculate, based on localized single-ion magnetism, that the relative energy scale of magnetic spin-orbital coupling on the Fe$^{2+}$ transition metal ion is important for the presence of a nematicity in the chalcogenides.
description: (13 pages, 10 figures, to be published in Physical Review B)
Liquid inertia versus bubble cloud buoyancy in circular plunging jet experiments
Creators: name: Dev, Narendra
name: Jerome}, {J. John Soundar
name: Scolan, Hélène
name: Matas, Jean-Philippe
Publisher: name: arXiv
Year: 2023
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: When a liquid jet plunges into a pool, it can generate a bubble-laden jet flow underneath the surface. This common and simple phenomenon is investigated experimentally for circular jets to illustrate and quantify the role played by the net gas/liquid void fraction on the maximum bubble penetration depth. It is first shown that an increase in either the impact diameter or the jet fall height to diameter ratio at constant impact momentum leads to a reduction in the bubble cloud size. By systematically measuring the local void fraction using optical probes in the biphasic jet, it is then demonstrated that this effect is a direct consequence of the increase in the air content within the cloud. A simple momentum balance model, including only inertia and the buoyancy force, is shown to predict the bubble cloud depth without any fitting parameters. Finally, a Froude number based on the bubble terminal velocity, the cloud depth, and also the net void fraction is introduced to propose a simple criterion for the threshold between the inertia-dominated and buoyancy-dominated regimes.
description: As of 16th of November 2023, it is accepted for publication in JFM
Calibrated Adaptive Teacher for Domain Adaptive Intelligent Fault Diagnosis
Creators: name: Forest, Florent
name: Fink, Olga
Publisher: name: arXiv
Year: 2023
Subjects: subject: Machine Learning (cs.LG)
subject: Artificial Intelligence (cs.AI)
subject: Signal Processing (eess.SP)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: I.2.6; J.2
subject: 68T07, 62H30

description: Intelligent Fault Diagnosis (IFD) based on deep learning has proven to be an effective and flexible solution, attracting extensive research. Deep neural networks can learn rich representations from vast amounts of representative labeled data for various applications. In IFD, they achieve high classification performance from signals in an end-to-end manner, without requiring extensive domain knowledge. However, deep learning models usually only perform well on the data distribution they have been trained on. When applied to a different distribution, they may experience performance drops. This is also observed in IFD, where assets are often operated in working conditions different from those in which labeled data have been collected. Unsupervised domain adaptation (UDA) deals with the scenario where labeled data are available in a source domain, and only unlabeled data are available in a target domain, where domains may correspond to operating conditions. Recent methods rely on training with confident pseudo-labels for target samples. However, the confidence-based selection of pseudo-labels is hindered by poorly calibrated confidence estimates in the target domain, primarily due to over-confident predictions, which limits the quality of pseudo-labels and leads to error accumulation. In this paper, we propose a novel UDA method called Calibrated Adaptive Teacher (CAT), where we propose to calibrate the predictions of the teacher network throughout the self-training process, leveraging post-hoc calibration techniques. We evaluate CAT on domain-adaptive IFD and perform extensive experiments on the Paderborn benchmark for bearing fault diagnosis under varying operating conditions. Our proposed method achieves state-of-the-art performance on most transfer tasks.
description: Accepted for publication in Sensors. 24 pages
Long-lived Particles Anomaly Detection with Parametrized Quantum Circuits
Creators: name: Bordoni, Simone
name: Stanev, Denis
name: Santantonio, Tommaso
name: Giagu, Stefano
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We investigate the possibility to apply quantum machine learning techniques for data analysis, with particular regard to an interesting use-case in high-energy physics. We propose an anomaly detection algorithm based on a parametrized quantum circuit. This algorithm has been trained on a classical computer and tested with simulations as well as on real quantum hardware. Tests on NISQ devices have been performed with IBM quantum computers. For the execution on quantum hardware specific hardware driven adaptations have been devised and implemented. The quantum anomaly detection algorithm is able to detect simple anomalies like different characters in handwritten digits as well as more complex structures like anomalous patterns in the particle detectors produced by the decay products of long-lived particles produced at a collider experiment. For the high-energy physics application, performance is estimated in simulation only, as the quantum circuit is not simple enough to be executed on the available quantum hardware. This work demonstrates that it is possible to perform anomaly detection with quantum algorithms, however, as amplitude encoding of classical data is required for the task, due to the noise level in the available quantum hardware, current implementation cannot outperform classic anomaly detection algorithms based on deep neural networks.
description: 22 pages, 14 figures
Flying Spin Qubits in Quantum Dot Arrays Driven by Spin-Orbit Interaction
Creators: name: Fernández-Fernández, D.
name: Ban, Yue
name: Platero, Gloria
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Quantum information transfer is fundamental for scalable quantum computing in any potential platform and architecture. Hole spin qubits, owing to their intrinsic spin-orbit interaction (SOI), promise fast quantum operations which are fundamental for the implementation of quantum gates. Yet, the influence of SOI in quantum transfer protocols remains an open question. Here, we investigate flying spin qubits mediated by SOI, using shortcuts to adiabaticity protocols, i.e., the long-range transfer of spin qubits and the quantum distribution of entangled pairs in semiconductor quantum dot arrays. We show that electric field manipulation allows dynamical control of the SOI, enabling simultaneously the implementation of quantum gates during the transfer, with the potential to significantly accelerate quantum algorithms. By harnessing the ability to perform quantum gates in parallel with the transfer, we implement dynamical decoupling schemes to focus and preserve the spin state, leading to higher transfer fidelity.
description: 27 pages, 14 figures, 1 table
Momentum-dependent quasiparticle properties of the Fermi polaron from the functional renormalization group
Creators: name: von Milczewski, Jonas
name: Schmidt, Richard
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: We study theoretically the lifetimes of attractive and repulsive Fermi polarons, as well as the molecule at finite momentum in three dimensions. To this end, we develop a new technique that allows for the computation of Green's functions in the whole complex frequency plane using exact analytical continuation within the functional renormalization group. The improved numerical stability and reduced computational cost of this method yield access to previously inaccessible momentum-dependent quasiparticle properties of low-lying excited states. While conventional approaches like the non-selfconsistent $T$-matrix approximation method cannot determine these lifetimes, we are able to find the momentum-dependent lifetime at different interaction strengths of both the attractive and repulsive polaron as well as the molecule. At weak coupling our results confirm predictions made from effective Fermi liquid theory regarding the decay of the attractive polaron, and we demonstrate that Fermi liquid-like behavior extends far into the strong-coupling regime where attractive polaron and molecule exhibit a $p^4$ momentum scaling in their decay widths. Our results offer an intriguing insight into the momentum-dependent quasiparticle properties of the Fermi polaron problem, which can be measured using techniques such as Raman transfer and Ramsey interferometry.
description: 18 pages, 5 figures
Morse predecomposition of an ivariant set
Creators: name: Lipiński, Michał
name: Mischaikow, Konstantin
name: Mrozek, Marian
Publisher: name: arXiv
Year: 2023
Subjects: subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics
subject: 37B30 37B20 37B35

description: Motivated by the study of the recurrent orbits in a Morse set of a Morse decomposition, we introduce the concept of Morse predecomposition of an isolated invariant set in the setting of combinatorial and classical dynamical systems. We prove that a Morse predecomposition indexed by a poset is a Morse decomposition and we show how a Morse predecomposition may be condensed back to a Morse decomposition.
description: 29 pages (31 with bibliography), 9 figures
Strong Error Bounds for Trotter & Strang-Splittings and Their Implications for Quantum Chemistry
Creators: name: Burgarth, Daniel
name: Facchi, Paolo
name: Hahn, Alexander
name: Johnsson, Mattias
name: Yuasa, Kazuya
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: Numerical Analysis (math.NA)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: Efficient error estimates for the Trotter product formula are central in quantum computing, mathematical physics, and numerical simulations. However, the Trotter error's dependency on the input state and its application to unbounded operators remains unclear. Here, we present a general theory for error estimation, including higher-order product formulas, with explicit input state dependency. Our approach overcomes two limitations of the existing operator-norm estimates in the literature. First, previous bounds are too pessimistic as they quantify the worst-case scenario. Second, previous bounds become trivial for unbounded operators and cannot be applied to a wide class of Trotter scenarios, including atomic and molecular Hamiltonians. Our method enables analytical treatment of Trotter errors in chemistry simulations, illustrated through a case study on the hydrogen atom. Our findings reveal: (i) for states with fat-tailed energy distribution, such as low-angular-momentum states of the hydrogen atom, the Trotter error scales worse than expected (sublinearly) in the number of Trotter steps; (ii) certain states do not admit an advantage in the scaling from higher-order Trotterization, and thus, the higher-order Trotter hierarchy breaks down for these states, including the hydrogen atom's ground state; (iii) the scaling of higher-order Trotter bounds might depend on the order of the Hamiltonians in the Trotter product for states with fat-tailed energy distribution. Physically, the enlarged Trotter error is caused by the atom's ionization due to the Trotter dynamics. Mathematically, we find that certain domain conditions are not satisfied by some states so higher moments of the potential and kinetic energies diverge. Our analytical error analysis agrees with numerical simulations, indicating that we can estimate the state-dependent Trotter error scaling genuinely.
description: 50 pages, 9 figures, 3 tables
Kernel Polynomial Method for Linear Spin Wave Theory
Creators: name: Lane, Harry
name: Zhang, Hao
name: Dahlbom, David
name: Quinn, Sam
name: Somma, Rolando D.
name: Mourigal, Martin
name: Batista, Cristian D.
name: Barros, Kipton
Publisher: name: arXiv
Year: 2023
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Calculating dynamical spin correlations is essential for matching model magnetic exchange Hamiltonians to momentum-resolved spectroscopic measurements. A major numerical bottleneck is the diagonalization of the dynamical matrix, especially in systems with large magnetic unit cells, such as those with incommensurate magnetic structures or quenched disorder. In this paper, we demonstrate an efficient scheme based on the kernel polynomial method for calculating dynamical correlations of relevance to inelastic neutron scattering experiments. This method reduces the scaling of numerical cost from cubic to linear in the magnetic unit cell size.
description: Submission to SciPost. 27 pages, 6 figures. Typos corrected, added additional minor comments to derivations
Preserving large-scale features in simulations of elastic turbulence
Creators: name: Yerasi, Sumithra R.
name: Picardo, Jason R.
name: Gupta, Anupam
name: Vincenzi, Dario
Publisher: name: arXiv
Year: 2023
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Chaotic Dynamics (nlin.CD)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: Simulations of elastic turbulence, the chaotic flow of highly elastic and inertialess polymer solutions, are plagued by numerical difficulties: The chaotically advected polymer conformation tensor develops extremely large gradients and can loose its positive definiteness, which triggers numerical instabilities. While efforts to tackle these issues have produced a plethora of specialized techniques -- tensor decompositions, artificial diffusion, and shock-capturing advection schemes -- we still lack an unambiguous route to accurate and efficient simulations. In this work, we show that even when a simulation is numerically stable, maintaining positive-definiteness and displaying the expected chaotic fluctuations, it can still suffer from errors significant enough to distort the large-scale dynamics and flow-structures. Focusing on two-dimensional simulations of the Oldroyd-B and FENE-P equations, we first compare two decompositions of the conformation tensor: symmetric square root (SSR) and Cholesky with a logarithmic transformation (Cholesky-log). While both simulations yield chaotic flows, only the Cholesky-log preserves the pattern of the forcing, i.e., its vortical cells remain ordered in a lattice as opposed to the vortices of the SSR simulations which shrink, expand and reorient constantly. To identify the accurate simulation, we appeal to a hitherto overlooked mathematical bound on the determinant of the conformation tensor, which unequivocally rejects the SSR simulation. Importantly, the accuracy of the Cholesky-log simulation is shown to arise from the logarithmic transformation. We then consider local artificial diffusion, a potential low-cost alternative to high-order advection schemes, and find unfortunately that it significantly modifies the dynamics. We end with an example, showing how the spurious large-scale motions identified here contaminate predictions of scalar mixing.
description: 24 pages, 11 figures
Six dimensional almost complex torus manifolds with Euler number six
Creators: name: Jang, Donghoon
name: Park, Jiyun
Publisher: name: arXiv
Year: 2023
Subjects: subject: Algebraic Topology (math.AT)
subject: Differential Geometry (math.DG)
subject: FOS: Mathematics

description: An almost complex torus manifold is a $2n$-dimensional compact connected almost complex manifold equipped with an effective action of a real $n$-dimensional torus $T^n \simeq (S^1)^n$ that has fixed points. For an almost complex torus manifold, there is a labeled directed graph which contains information on weights at the fixed points and isotropy spheres.
 Let $M$ be a 6-dimensional almost complex torus manifold with Euler number 6. We show that two types of graphs occur for $M$, and for each type of graph we construct such a manifold $M$, proving the existence. Using the graphs, we determine the Chern numbers and the Hirzebruch $χ_y$-genus of $M$.
SCALE 2019 Physical supply mechanisms data
Creators: name: Ramalepe, Thapelo
name: SAMANTA, SAUMIK
name: Cloete, Ryan
name: Ryan-Keogh, Thomas
name: Roychoudhury, Alakendra
Publisher: name: Zenodo
Year: 2023

description: The attached file contains manganese data, including various calculations such as:

Winter Entrainment

Diapycnal Diffusion

Equatorwards Lateral advection

Ekman pumping

Spring Detrainment

Please note that during winter, inclement weather conditions allowed for sampling only eight stations instead of the originally intended ten. Consequently, flux calculations for winter are based on data collected from these eight stations. Two methods of calculations are included in the spreadsheet.
Combining General and Personalized Models for Epilepsy Detection with Hyperdimensional Computing
Creators: name: Pale, Una
name: Teijeiro, Tomas
name: Atienza, David
Publisher: name: arXiv
Year: 2023
Subjects: subject: Neural and Evolutionary Computing (cs.NE)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Epilepsy is a chronic neurological disorder with a significant prevalence. However, there is still no adequate technological support to enable epilepsy detection and continuous outpatient monitoring in everyday life. Hyperdimensional (HD) computing is an interesting alternative for wearable devices, characterized by a much simpler learning process and also lower memory requirements. In this work, we demonstrate a few additional aspects in which HD computing, and the way its models are built and stored, can be used for further understanding, comparing, and creating more advanced machine learning models for epilepsy detection. These possibilities are not feasible with other state-of-the-art models, such as random forests or neural networks. We compare inter-subject similarity of models per different classes (seizure and non-seizure), then study the process of creation of generalized models from personalized ones, and in the end, how to combine personalized and generalized models to create hybrid models. This results in improved epilepsy detection performance. We also tested knowledge transfer between models created on two different datasets. Finally, all those examples could be highly interesting not only from an engineering perspective to create better models for wearables, but also from a neurological perspective to better understand individual epilepsy patterns.