cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
On the origin of critical temperature enhancement in atomically-thin superconductors
Creators: name: Talantsev, Evgeny
name: Crump, Wayne
name: Island, Joshua
name: Xing, Ying
name: Sun, Yi
name: Wang, Jian
name: Tallon, Jeffery
Publisher: name: arXiv
Year: 2017
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Recent experiments showed that thinning gallium, iron selenide and 2H tantalum disulfide to single/several monoatomic layer(s) enhances their superconducting critical temperatures. Here, we characterize these superconductors by extracting the absolute values of the London penetration depth, the superconducting energy gap, and the relative jump in specific heat at the transition temperature from their self-field critical currents. Our central finding is that the enhancement in transition temperature for these materials arises from the opening of an additional superconducting gap, while retaining a largely unchanged bulk superconducting gap. Literature data reveals that ultrathin niobium films similarly develop a second superconducting gap. Based on the available data, it seems that, for type-II superconductors, a new superconducting band appears when the film thickness becomes smaller than the out-of-plane coherence length. The same mechanism may also be the cause of enhanced interface superconductivity.
description: 43 pages, 12 figures
Jet Production at RHIC and LHC
Creators: name: Cunqueiro, Leticia
Publisher: name: arXiv
Year: 2017
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: Recent results on jet production in heavy ion collisions at RHIC and the LHC are discussed, with emphasis on inclusive jet yields and semi-inclusive hadron-triggered and vector boson-triggered recoil jet yields as well as their azimuthal angular correlations. I will also discuss the constraints that these observables impose on the opacity of the medium, the flavour dependence of energy loss, the interplay of perturbative and non perturbative effects and the change of the degrees of freedom of the medium with the resolution of the probe.
description: 8 pages, 7 figures, proceedings of Quark Matter 2017 conference
Phenotypic characterization of the Gamo highland sheep population in Gamo Zone, South Ethiopia
Creators: name: Dea, Dereje
name: Eramo, Ermias
name: Gemiyo, Deribe
Publisher: name: Journal of Agriculture and Environmental Sciences
Year: 2023

description: The study aimed to identify physical characteristics and prediction of live weight using linear body measurements of indigenous sheep types in two highland districts of the Gamo zone (Chencha and Qogota). Districts were purposively selected whereas farmers and animals were randomly selected. About 335 mature sheep (270 female and 65 male) were sampled for the body measurements. Both qualitative and quantitative data were analysed using SPSS version (20). Overall, the current findings revealed that mixed (62.50%) followed by black (21.90%) were the dominant coat colours with patchy coat colour patterns (56.30%). The majority of the sheep were horned (62.5%), curved horn (67.50%) and obliquely backward horn types (77.50%). Horizontal ear orientation (76.00%) and straight head profile (96.90) were predominantly observed. In general, about 71.60% of the sheep were hairy type and had straight crimp-curled hair (73.60%). The total hair coverage on the head, face, belly and leg was about 3.0%, 94%, 92.5% and 13.4%, respectively. About 55.20% of the study sheep revealed near hocks tail length. The mean body weight, body length, height at wither, chest girth, horn length, head length, hair length, ear length and tail length were 20.26±3.60 kg, 54.55±3.48, 55.13±3.83, 66.73±4.79, 9.42±7.46, 16.83±1.85, 7.41±3.12, 10.27±0.97 and 26.62±2.66 cm, respectively. In general, sex, district and age (dentition) significantly (P<0.05) affected linear body measurements. Body weight and most of the linear body measurements were positively correlated. Chest girth was the single best predictor of body weight (P<0.05). Molecular characterization of Gamo highland sheep is recommended for further advanced breeding strategies.
description: Journal of Agriculture and Environmental Sciences, Vol 8 No 1 (2023)
DBI from Gravity
Creators: name: Maxfield, Travis
name: Sethi, Savdeep
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study the dynamics of gravitational lumps. By a lump, we mean a metric configuration that asymptotes to a flat space-time. Such lumps emerge in string theory as strong coupling descriptions of D-branes. We provide a physical argument that the broken global symmetries of such a background, generated by certain large diffeomorphisms, constrain the dynamics of localized modes. These modes include the translation zero modes and any localized tensor modes. The constraints we find are gravitational analogues of those found in brane physics. For the example of a Taub-NUT metric in eleven-dimensional supergravity, we argue that a critical value for the electric field arises from standard gravity without higher derivative interactions.
description: 31 pages, LaTeX; references added
Linear correlations of the divisor function
Creators: name: Bettin, Sandro
Publisher: name: arXiv
Year: 2017
Subjects: subject: Number Theory (math.NT)
subject: FOS: Mathematics
subject: 11M41, 11N37, 11D72 (primary)

description: Motivated by arithmetic applications on the number of points in a bihomogeneous variety and on moments of Dirichlet $L$-functions, we provide analytic continuation for the series $\mathcal A_{\boldsymbol{a}}(s):=\sum_{n_1,\dots,n_k\geq1}\frac{d(n_1)\cdots d(n_k)}{(n_1\cdots n_k)^{s}}$ with the sum restricted to solutions of a non-trivial linear equation $a_1n_1+\cdots+a_kn_k=0$. The series $\mathcal A_{\boldsymbol{a}}(s)$ converges absolutely for $\Re(s)>1-\frac1k$ and we show it can be meromorphically continued to $\Re(s)>1-\frac 2{k+1}$ with poles at $s=1-\frac1{k-j}$ only, for $1\leq j< (k-1)/2$. As an application, we obtain an asymptotic formula with power saving error term for the number of points in the variety $a_1x_1y_1+\cdots+a_kx_ky_k=0$ in $\mathbb P^{k-1}(\mathbb Q)\times \mathbb P^{k-1}(\mathbb Q)$.
description: 49 pages
Without Borders: Anarchist conference & Festival July 20-25, 1989 San Francisco Guide Book
Creators: name: :Unav
Publisher: name: University of Victoria Libraries
Year: 2020
Subjects: subject: Anarchism--Societies, etc.
valueUri: http://id.worldcat.org/fast/808396
subject: Civil disobedience
valueUri: http://id.worldcat.org/fast/862481
subject: Demonstrations
valueUri: http://id.worldcat.org/fast/890222
subject: Anarchism
valueUri: http://id.worldcat.org/fast/808387
subject: Anarchists
valueUri: http://id.worldcat.org/fast/808401
subject: Political participation
valueUri: http://id.worldcat.org/fast/1069386
subject: Congresses and conventions
valueUri: http://id.worldcat.org/fast/875219
subject: Protest movements
valueUri: http://id.worldcat.org/fast/1079826
subject: Social groups
valueUri: http://id.worldcat.org/fast/1122482

description: A guide book to the 4th annual Without Borders Anarchist Conference and Festival in San Francisco. Includes information about the conference like workshops and the conference schedule along with practical information for childcare, local resources, what to wear, housing, food, and maps,
Using the Tsallis distribution for hadron spectra in $pp$ collisions: Pions and quarkonia at $\sqrt{s}$ = 5--13000 GeV
Creators: name: Grigoryan, Smbat
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: A thermal model, based on the Tsallis distribution and blast-wave model, is proposed to compute hadron double-differential spectra $d^{2}N/dp_{T}dy$ in $pp$ (also high energy $p\overline{p}$) collisions. It successfully describes the available experimental data on pion and quarkonia ($ϕ$, $J/ψ$, $ψ(2S)$, $Υ$ family) production at energies from $\sqrt{s} = 5$ GeV to the LHC ones. Simple parametrizations for the $\sqrt{s}$ dependence of the model parameters are provided allowing predictions for the yields of these particles at new collision energies. The model can be used also for the pion Bose-Einstein correlation studies.
description: 15 pages, 20 figures
A Tale of Two Portals: Testing Light, Hidden New Physics at Future $e^+ e^-$ Colliders
Creators: name: Liu, Jia
name: Wang, Xiao-Ping
name: Yu, Felix
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We investigate the prospects for producing new, light, hidden states at a future $e^+ e^-$ collider in a Higgsed dark $U(1)_D$ model, which we call the Double Dark Portal model. The simultaneous presence of both vector and scalar portal couplings immediately modifies the Standard Model Higgsstrahlung channel, $e^+ e^- \to Zh$, at leading order in each coupling. In addition, each portal leads to complementary signals which can be probed at direct and indirect detection dark matter experiments. After accounting for current constraints from LEP and LHC, we demonstrate that a future $e^+ e^-$ Higgs factory will have unique and leading sensitivity to the two portal couplings by studying a host of new production, decay, and radiative return processes. Besides the possibility of exotic Higgs decays, we highlight the importance of direct dark vector and dark scalar production at $e^+ e^-$ machines, whose invisible decays can be tagged from the recoil mass method.
description: 47 pages, 9 figures, 1 table. v2: references added, version matched to JHEP
Collinear cluster tri-partition: Kinematics constraints and stability of collinearity
Creators: name: Holmvall, Patric
name: Köster, Ulli
name: Heinz, Andreas
name: Nilsson, Thomas
Publisher: name: arXiv
Year: 2016
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: A new mode of nuclear fission has been proposed by the FOBOS collaboration, called Collinear Cluster Tri-partition (CCT), suggesting that three heavy fission fragments can be emitted perfectly collinearly in low-energy fission. It is surprising that CCT escaped observation for so long given the relatively high reported yield, of roughly 0.5% relative to binary fission. These claims call for an independent verification with a different experimental technique. Verification experiments based on direct observation of CCT fragments with fission fragment spectrometers require guidance with respect to the allowed kinetic energy range, which we present in this paper. We discuss corresponding model calculations which, if CCT is found in such verification experiments, could indicate how the breakups proceed. We also study the intrinsic stability of collinearity. Three different decay models are used, which span together the timescales of three-body fission. These models are used to calculate the possible kinetic energy ranges of CCT fragments in 235U(n,f) and 252Cf(sf). We use semi-classical trajectory calculations with a Monte-Carlo method to study the intrinsic stability of collinearity. CCT has a high net Q-value, but in a sequential decay, the intermediate steps are energetically and geometrically unfavorable or even forbidden. Moreover, perfect collinearity is extremely unstable, and broken by the slightest perturbation. According to our results, the central fragment would be very difficult to detect due to its low kinetic energy, raising the question of why previous experiments could not detect a missing-mass signature corresponding to CCT. We find that a realization of CCT would require an unphysical fine-tuning of the initial conditions. Our results enable independent experimental verification and encourage further critical theoretical studies of CCT.
description: 20 pages, 19 figures
The nearest ultra diffuse galaxy: UGC2162
Creators: name: Trujillo, Ignacio
name: Román, Javier
name: Filho, Mercedes
name: Almeida, Jorge Sánchez
Publisher: name: arXiv
Year: 2017
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We describe the structural, stellar population and gas properties of the nearest Ultra Diffuse Galaxy (UDG) discovered so far: UGC2162 (z=0.00392; R$_{e,g}$=1.7$(\pm$0.2) kpc; $μ_g(0)$=24.4$\pm$0.1 mag/arcsec$^2$; g-i=0.33$\pm$0.02). This galaxy, located at a distance of 12.3($\pm$1.7) Mpc, is a member of the M77 group. UGC2162 has a stellar mass of $\sim$2($^{+2}_{-1}$)$\times$10$^7$ M$_\odot$ and is embedded within a cloud of HI gas $\sim$10 times more massive: $\sim$1.9($\pm$0.6)$\times$10$^8$ M$_\odot$. Using the width of its HI line as a dynamical proxy, the enclosed mass within the inner R$\sim$5 kpc is $\sim$4.6($\pm$0.8)$\times$10$^9$ M$_\odot$ (i.e. M/L$\sim$200). The estimated virial mass from the cumulative mass curve is $\sim$8($\pm$2)$\times$10$^{10}$ M$_\odot$. Ultra-deep imaging from the IAC Stripe82 Legacy Project show that the galaxy is irregular and has many star forming knots, with a gas-phase metallicity around one-third of the solar value. Its estimated Star Formation Rate (SFR) is $\sim$0.01 M$_\odot$/yr. This SFR would double the stellar mass of the object in $\sim$2 Gyr. If the object were to stop forming stars at this moment, after a passive evolution, its surface brightness would become extremely faint: $μ_g(0)$$\sim$27 mag/arcsec$^2$ and its size would remain large R$_{e,g}$$\sim$ 1.8 kpc. Such faintness would make it almost undetectable to most present-day surveys. This suggests that there could be an important population of M$_{\star}$$\sim$10$^7$ M$_\odot$ "dark galaxies" in rich environments (depleted of HI gas) waiting to be discovered by current and future ultra-deep surveys.
description: 5 pages; 3 figures, accepted for publication in ApJ; minor changes to match the published version
Letter from Lilian Bowes Lyon to Herbert Read, January 18, 1949
Creators: name: Bowes-Lyon, Lilian Helen, 1895-1949
Publisher: name: University of Victoria Libraries
Year: 2023
Subjects: subject: Anarchists
valueUri: http://id.worldcat.org/fast/808401
subject: Poetry
valueUri: http://id.worldcat.org/fast/1423828
subject: Authors, English
valueUri: http://id.worldcat.org/fast/821945
subject: Poets
valueUri: http://id.worldcat.org/fast/1067778
subject: Art historians
valueUri: http://id.worldcat.org/fast/815554
subject: Authors
valueUri: http://id.worldcat.org/fast/821688
subject: Bowes-Lyon, Lilian Helen, 1895-1949
valueUri: http://id.worldcat.org/fast/91563
subject: Read, Herbert, 1893-1968
valueUri: http://id.worldcat.org/fast/1754386
subject: Poets, English
valueUri: http://id.worldcat.org/fast/1067870

description: Part of a collection of correspondence between Sir Herbert Read and British poet Lilian Bowes Lyon. In addition to writing, Bowes Lyon was heavily involved in volunteer work in both World Wars. She also lived with Buerger’s Disease, which required her to have multiple amputations, and lead to her early death in 1949. In this letter, Bowes Lyon wishes Read a Happy New Year, then describes how a letter from him from the previous August turned up, and proceeds to respond to it in detail. She compliments the poems in it and encourages Read to visit when he is tired of London. Bowes Lyon goes on to express the challenges of chronic pain. In closing, she writes that she hopes Read's children and beechwood are all doing well.
Young Galaxy Candidates in the Hubble Frontier Fields IV. MACS J1149.5+2223
Creators: name: Zheng, W.
name: Zitrin, A.
name: Infante, L.
name: Laporte, N.
name: Huang, X. X.
name: Moustakas, J.
name: Ford, H. C.
name: Shu, X. W.
name: Wang, J. X.
name: Diego, J. M.
name: Bauer, F. E.
name: Iribarren, P. T.
name: Broadhurst, T.
name: Molino, A.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We search for high-redshift dropout galaxies behind the Hubble Frontier Fields (HFF) galaxy cluster MACS J1149.5+2223, a powerful cosmic lens that has revealed a number of unique objects in its field. Using the deep images from the Hubble and Spitzer space telescopes, we find 11 galaxies at z>7 in the MACS J1149.5+2223 cluster field, and 11 in its parallel field. The high-redshift nature of the bright z~9.6 galaxy MACS1149-JD, previously reported by Zheng et al., is further supported by non-detection in the extremely deep optical images from the HFF campaign. With the new photometry, the best photometric redshift solution for MACS1149-JD reduces slightly to z=9.44 +/- 0.12. The young galaxy has an estimated stellar mass of (7 +/- 2)X10E8 Msun, and was formed at z=13.2 +1.9-1.6 when the universe was ~300 Myr old. Data available for the first four HFF clusters have already enabled us to find faint galaxies to an intrinsic magnitude of M(UV) ~ -15.5, approximately a factor of ten deeper than the parallel fields.
description: To appear in the Astrophysical Journal. 20 pages, 6 figures, 3 tables. arXiv admin note: text overlap with arXiv:1402.6743
Mas del Gleix, cargolade. Escargots crus placés sur le grill près du feu
Creators: name: Musée National Des Arts Et Traditions Populaires (Paris)
name: Centre D'ethnologie Française
Publisher: name: École des Hautes Études en Sciences Sociales; Institut  interdisciplinaire d'anthropologie du contemporain (Paris); Laboratoire d'anthropologie et d'histoire de l'institution de la culture (Paris)
Year: 2022

Abstract
Four-fermion interactions and the chiral symmetry breaking in an external magnetic field
Creators: name: Fu, Wei-jie
name: Liu, Yu-xin
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We investigate the chiral symmetry and its spontaneous breaking at finite temperature and in an external magnetic field with four-fermion interactions of different channels. Quantum and thermal fluctuations are included within the functional renormalization group approach, and properties of the set of flow equations for different couplings, such as its fixed points, are discussed. It is found that external parameters, e.g. the temperature and the external magnetic field and so on, do not change the structure of the renormalization group flows for the couplings. The flow strength is found to be significantly dependent on the route and direction in the plane of couplings of different channels. Therefore, the critical temperature for the chiral phase transition shows a pronounced dependence on the direction as well. Given fixed initial ultraviolet couplings, the critical temperature increases with the increasing magnetic field, viz., the magnetic catalysis is observed with initial couplings fixed.
description: 8 pages, 4 figures
Mob Action Against the State: Haymarket Remembered
Creators: name: :Unav
Publisher: name: University of Victoria Libraries
Year: 2020
Subjects: subject: Congresses and conventions
valueUri: http://id.worldcat.org/fast/875219
subject: Civil disobedience
valueUri: http://id.worldcat.org/fast/862481
subject: Anarchism
valueUri: http://id.worldcat.org/fast/808387
subject: Social groups
valueUri: http://id.worldcat.org/fast/1122482
subject: Demonstrations
valueUri: http://id.worldcat.org/fast/890222
subject: Political participation
valueUri: http://id.worldcat.org/fast/1069386
subject: Protest movements
valueUri: http://id.worldcat.org/fast/1079826
subject: Anarchism--Societies, etc.
valueUri: http://id.worldcat.org/fast/808396
subject: Haymarket Square Riot (Chicago, Illinois : 1886)
valueUri: http://id.worldcat.org/fast/1404551
subject: Direct action
valueUri: http://id.worldcat.org/fast/894518
subject: Anarchists
valueUri: http://id.worldcat.org/fast/808401

description: Essays and other contributions describing the Haymarket general strike and riot of 1886 and the 100th anniversary gathering hosted by the Chicago Anarchist Group in May 1986 and the events surrounding it.
Computing stationary solutions of the two-dimensional Gross-Pitaevskii equation with Deflated continuation
Creators: name: Charalampidis, E. G.
name: Kevrekidis, P. G.
name: Farrell, P. E.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Pattern Formation and Solitons (nlin.PS)
subject: Dynamical Systems (math.DS)
subject: Numerical Analysis (math.NA)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: In this work we employ a recently proposed bifurcation analysis technique, the deflated continuation algorithm, to compute steady-state solitary waveforms in a one-component, two dimensional nonlinear Schrödinger equation with a parabolic trap and repulsive interactions. Despite the fact that this system has been studied extensively, we discover a wide variety of previously unknown branches of solutions. We analyze the stability of the newly discovered branches and discuss the bifurcations that relate them to known solutions both in the near linear (Cartesian, as well as polar) and in the highly nonlinear regimes. While deflated continuation is not guaranteed to compute the full bifurcation diagram, this analysis is a potent demonstration that the algorithm can discover new nonlinear states and provide insights into the energy landscape of complex high-dimensional Hamiltonian dynamical systems.
description: 17 pages, 11 figures
Letter from Ford Madox Ford to Herbert Read, October 05, 1921
Creators: name: Ford, Ford Madox, 1873-1939
Publisher: name: University of Victoria Libraries
Year: 2023
Subjects: subject: Poets
valueUri: http://id.worldcat.org/fast/1067778
subject: Read, Herbert, 1893-1968
valueUri: http://id.worldcat.org/fast/1754386
subject: Critics
valueUri: http://id.worldcat.org/fast/883769
subject: Authors, English
valueUri: http://id.worldcat.org/fast/821945
subject: Authors
valueUri: http://id.worldcat.org/fast/821688
subject: Ford, Ford Madox, 1873-1939
valueUri: http://id.worldcat.org/fast/289558
subject: Art historians
valueUri: http://id.worldcat.org/fast/815554
subject: Poets, English
valueUri: http://id.worldcat.org/fast/1067870
subject: Novelists, English
valueUri: http://id.worldcat.org/fast/1039718
subject: Anarchists
valueUri: http://id.worldcat.org/fast/808401

description: Part of a collection of friendly correspondence between Sir Herbert Read and novelist, literary critic, and editor, Ford Madox Ford. In this letter Ford discusses newspaper articles and business details of his writing work.
Rattleback dynamics and its reversal time of rotation
Creators: name: Kondo, Yoichiro
name: Nakanishi, Hiizu
Publisher: name: arXiv
Year: 2017
Subjects: subject: Classical Physics (physics.class-ph)
subject: FOS: Physical sciences

description: A rattleback is a rigid, semi-elliptic toy which exhibits unintuitive behavior; when it is spun in one direction, it soon begins pitching and stops spinning, then it starts to spin in the opposite direction, but in the other direction, it seems to spin just steadily. This puzzling behavior results from the slight misalignment between the principal axes for the inertia and those for the curvature; the misalignment couples the spinning with the pitching and the rolling oscillations. It has been shown that under the no-slip condition and without dissipation the spin can reverse in both directions, and Garcia and Hubbard obtained the formula for the time required for the spin reversal $t_r$ [Proc. R. Soc. Lond. A 418, 165-197 (1988) ]. In this work, we reformulate the rattleback dynamics in a physically transparent way and reduce it to a three-variable dynamics for spinning, pitching, and rolling. We obtain an expression of the Garcia-Hubbard formula for $t_r$ by a simple product of four factors: (1) the misalignment angle, (2) the difference in the inverses of inertia moment for the two oscillations, (3) that in the radii for the two principal curvatures, and (4) the squared frequency of the oscillation. We perform extensive numerical simulations to examine validity and limitation of the formula, and find that (1) the Garcia-Hubbard formula is good for both spinning directions in the small spin and small oscillation regime, but (2) in the fast spin regime especially for the steady direction, the rattleback may not reverse and shows a rich variety of dynamics including steady spinning, spin wobbling, and chaotic behavior reminiscent of chaos in a dissipative system.
description: Fig.2 updated. to appear in Phys. Rev. E
Quasi Bound States in the Continuum with Few Unit Cells of Photonic Crystal Slab
Creators: name: Taghizadeh, Alireza
name: Chung, Il-Sug
Publisher: name: arXiv
Year: 2017
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Bound states in the continuum (BICs) in photonic crystal slabs represent the resonances with an infinite quality(Q)-factor, occurring above the light line for an infinitely periodic structure. We show that a set of BICs can turn into quasi-BICs with a very high Q-factor even for two or three unit cell structures. They are explained by a viewpoint of BICs originating from the tight binding of individual resonances of each unit cell as in semiconductors. Combined with a reciprocal-space matching technique, the microcavities based on quasi-BICs can achieve a Q-factor as high as defect-based PhC microcavities. These results may enable experimental studies of BICs in a compact platform as well as realizing a new concept of high-Q mirrorless microcavities.
description: 4 pages, 5 figures
Quantum embedding theories
Creators: name: Sun, Qiming
name: Chan, Garnet Kin-Lic
Publisher: name: arXiv
Year: 2016
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: In complex systems, it is often the case that the region of interest forms only one part of a much larger system. The idea of joining two different quantum simulations - a high level calculation on the active region of interest, and a low level calculation on its environment - formally defines a quantum embedding. While any combination of techniques constitutes an embedding, several rigorous formalisms have emerged that provide for exact feedback between the embedded system and its environment. These three formulations: it density functional embedding, Green's function embedding, and density matrix embedding, respectively use the single-particle density, single-particle Green's function, and single-particle density matrix as the quantum variables of interest. Many excellent reviews exist covering these methods individually. However, a unified presentation of the different formalisms is so far lacking. Indeed, the various languages commonly used: functional equations for density functional embedding; diagrammatics for Green's function embedding; and entanglement arguments for density matrix embedding, make the three formulations appear vastly different. In this account, we introduce the basic equations of all three formulations in such a way as to highlight their many common intellectual strands. While we focus primarily on a straightforward theoretical perspective, we also give a brief overview of recent applications, and possible future developments.
Internal structure and stability of vortices in a dipolar spinor Bose-Einstein condensate
Creators: name: Borgh, Magnus O.
name: Lovegrove, Justin
name: Ruostekoski, Janne
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: We demonstrate how dipolar interactions can have pronounced effects on the structure of vortices in atomic spinor Bose-Einstein condensates and illustrate generic physical principles that apply across dipolar spinor systems. We then find and analyze the cores of singular vortices with non-Abelian charges in the point-group symmetry of a spin-3 $^{52}$Cr condensate. Using a simpler model system, we analyze the underlying dipolar physics and show how a characteristic length scale arising from the magnetic dipolar coupling interacts with the hierarchy of healing lengths of the s-wave scattering, and leads to simple criteria for the core structure: When the interactions both energetically favor the ground-state spin condition, such as in the spin-1 ferromagnetic phase, the size of singular vortices is restricted to the shorter spin-dependent healing length. Conversely, when the interactions compete (e.g., in the spin-1 polar phase), we find that the core of a singular vortex is enlarged by increasing dipolar coupling. We further demonstrate how the spin-alignment arising from the interaction anisotropy is manifest in the appearance of a ground-state spin-vortex line that is oriented perpendicularly to the condensate axis of rotation, as well as in potentially observable internal core spin textures. We also explain how it leads to interaction-dependent angular momentum in nonsingular vortices as a result of competition with rotation-induced spin ordering. When the anisotropy is modified by a strong magnetic field, we show how it gives rise to a symmetry-breaking deformation of a vortex core into a spin-domain wall.
description: Accepted for publication in Phys. Rev. A (13 pages, 5 figures)
Fluctuation-induced forces in confined ideal and imperfect Bose gases
Creators: name: Diehl, H. W.
name: Rutkevich, Sergei B.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Fluctuation-induced forces are investigated for ideal and imperfect Bose gases confined to $d$-dimensional films of size $\infty^{d-1}\times D$ under periodic (P), antiperiodic (A), Dirichlet-Dirichlet (DD), Neumann-Neumann (NN), and Robin (R) boundary conditions (BCs). The full scaling functions $Υ^{\text{BC}}_d(x_λ=D/λ_{th},{x_ξ=D/ξ})$ of the residual reduced grand potential per area, $φ_{\text{res},d}^{\text{BC}}(T,μ,D)=D^{-(d-1)}Υ_d^{\text{BC}}(x_λ,x_ξ)$, are determined for the ideal gas case with these BCs, where $λ_{th}$ and $ξ$ are the thermal de-Broglie wavelength and the bulk correlation length, respectively. The scaling functions $Θ^{\text{BC}}_d(x_ξ)\equiv Υ_d^{\text{BC}}(\infty,x_ξ)$ describing the critical behavior at the bulk condensation transition are shown to agree with those previously determined from a massive free $O(2)$ theory for $\text{BC}=\text{P},\text{A},\text{DD},\text{DN},\text{NN}$. For $d=3$, they are expressed in closed analytical form. The analogous functions $Υ_d^{\text{BC}}(x_λ,x_ξ,c_1D,c_2D)$ and $Θ^{\text{R}}_d(x_ξ,c_1D,c_2D)$ under the RBCs $(\partial_z-c_1)ϕ|_{z=0}=(\partial_z+c_2)ϕ|_{z=D}=0$ with $c_1\ge 0$ and $c_2\ge 0$ are also determined. The functions $Υ_{\infty,d}^{\text{P}}(x_λ,x_ξ)$ and $Φ_{\infty,d}^{\text{P}}(x_ξ)$ for the imperfect Bose gas are shown to agree with those of the interacting Bose gas with $n\to\infty$ internal degrees of freedom. Hence for ${d=3}$, $Φ_{\infty,d}^{\text{P}}(x_ξ)$ is known exactly in closed analytic form. A modified imperfect Bose-gas model with free BC is introduced that corresponds to the limit $n\to\infty$ of this interacting Bose gas. Exact results for the function $Θ_{\infty,3}^{\mathbb{DD}}(x_ξ)$ therefore follow from those of the $O(2n)$ $ϕ^4$ model for $n\to\infty$.
description: pdf-LaTeX, 24 pages; minor additions, cosmetic modifications, and typos corrected
Postcard from Bertrand Russell to Douglas Goldring, January 10, 1920
Creators: name: Russell, Bertrand, 1872-1970
Publisher: name: University of Victoria Libraries
Year: 2022
Subjects: subject: Authors
valueUri: http://id.worldcat.org/fast/821688
subject: Russell, Bertrand, 1872-1970
valueUri: http://id.worldcat.org/fast/35776
subject: Mathematicians
valueUri: http://id.worldcat.org/fast/1012154
subject: Authors, English
valueUri: http://id.worldcat.org/fast/821945
subject: Journalists
valueUri: http://id.worldcat.org/fast/984188
subject: Literature, Modern
valueUri: http://id.worldcat.org/fast/1000172
subject: Goldring, Douglas, 1887-1960
valueUri: http://id.worldcat.org/fast/1798259
subject: Philosophers
valueUri: http://id.worldcat.org/fast/1060746
subject: Modernism (Literature)
valueUri: http://id.worldcat.org/fast/1024455
subject: Logicians
valueUri: http://id.worldcat.org/fast/1002081

description: Postcard to Douglas Goldring from Bertrand Russell (British mathematician, philosopher, and logician).
Reduction of dynatomic curves
Creators: name: Doyle, John R.
name: Krieger, Holly
name: Obus, Andrew
name: Pries, Rachel
name: Rubinstein-Salzedo, Simon
name: West, Lloyd W.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Dynamical Systems (math.DS)
subject: Algebraic Geometry (math.AG)
subject: Number Theory (math.NT)
subject: FOS: Mathematics
subject: 37F45, 37P05, 37P35, 37P45, 11G20, 11S15, 14H30

description: The dynatomic modular curves parametrize polynomial maps together with a point of period $n$. It is known that the dynatomic curves $Y_1(n)$ are smooth and irreducible in characteristic 0 for families of polynomial maps of the form $f_c(z) = z^m +c$ where $m\geq 2$. In the present paper, we build on the work of Morton to partially characterize the primes $p$ for which the reduction modulo $p$ of $Y_1(n)$ remains smooth and/or irreducible. As an application, we give new examples of good reduction of $Y_1(n)$ for several primes dividing the ramification discriminant when $n=7,8,11$. The proofs involve arithmetic and complex dynamics, reduction theory for curves, ramification theory, and the combinatorics of the Mandelbrot set.
description: 47 pages, 2 figures; fixed typos and added some data to Appendix A
Letter from Eric Gill to Herbert Read, August 20, 1934
Creators: name: Gill, Eric, 1882-1940
Publisher: name: University of Victoria Libraries
Year: 2023
Subjects: subject: Printmakers
valueUri: http://id.worldcat.org/fast/1076809
subject: Authors
valueUri: http://id.worldcat.org/fast/821688
subject: Poets
valueUri: http://id.worldcat.org/fast/1067778
subject: Gill, Eric, 1882-1940
valueUri: http://id.worldcat.org/fast/9187
subject: Authors, English
valueUri: http://id.worldcat.org/fast/821945
subject: Artists' books
valueUri: http://id.worldcat.org/fast/817660
subject: Poets, English
valueUri: http://id.worldcat.org/fast/1067870
subject: Anarchists
valueUri: http://id.worldcat.org/fast/808401
subject: Read, Herbert, 1893-1968
valueUri: http://id.worldcat.org/fast/1754386
subject: Sculptors
valueUri: http://id.worldcat.org/fast/1109473
subject: Art historians
valueUri: http://id.worldcat.org/fast/815554
subject: Artists
valueUri: http://id.worldcat.org/fast/817559

description: Part of a collection of correspondence from Eric Gill to Sir Herbert Read. Gill was a renowned early 20th century English printmaker, typeface designer, and sculptor. In this letter, Gill defends his latest book from certain statements in a review by Read.
A supernova at 50 pc: Effects on the Earth's atmosphere and biota
Creators: name: Melott, A. L
name: Thomas, B. C.
name: Kachelriess, M.
name: Semikoz, D. V.
name: Overholt, A. C.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Geophysics (physics.geo-ph)
subject: Populations and Evolution (q-bio.PE)
subject: FOS: Physical sciences
subject: FOS: Biological sciences

description: Recent 60Fe results have suggested that the estimated distances of supernovae in the last few million years should be reduced from 100 pc to 50 pc. Two events or series of events are suggested, one about 2.7 million years to 1.7 million years ago, and another may at 6.5 to 8.7 million years ago. We ask what effects such supernovae are expected to have on the terrestrial atmosphere and biota. Assuming that the Local Bubble was formed before the event being considered, and that the supernova and the Earth were both inside a weak, disordered magnetic field at that time, TeV-PeV cosmic rays at Earth will increase by a factor of a few hundred. Tropospheric ionization will increase proportionately, and the overall muon radiation load on terrestrial organisms will increase by a factor of 150. All return to pre-burst levels within 10kyr. In the case of an ordered magnetic field, effects depend strongly on the field orientation. The upper bound in this case is with a largely coherent field aligned along the line of sight to the supernova, in which case TeV-PeV cosmic ray flux increases are 10^4; in the case of a transverse field they are below current levels. We suggest a substantial increase in the extended effects of supernovae on Earth and in the lethal distance estimate; more work is needed.This paper is an explicit followup to Thomas et al. (2016). We also here provide more detail on the computational procedures used in both works.
description: 5 figures. Revised version to be published in ApJ
Hawking radiation from the holographic screen
Creators: name: Zhao, Ying-Jie
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: In this paper we generalize the Parikh-Wilczek scheme to a holographic screen in the framework of the ultraviolet self-complete quantum gravity. We calculate that the tunneling probabilities of the massless and massive particles depend on their energies of the particles and the mass of the holographic screen. The radiating temperature has not been the standard Hawking temperature. On the contrary, the quantum unitarity principle always remains.
description: 2 figures
Estimation of bipolar jets from accretion discs around Kerr black holes
Creators: name: Kumar, Rajiv
name: Chattopadhyay, Indranil
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We analyse flows around a rotating black hole and obtain self-consistent accretion-ejection solutions in full general relativistic prescription. Entire energy-angular momentum parameter space is investigated in the advective regime to obtain shocked and shock-free accretion solutions. Jet equations of motion are solved along the von-Zeipel surfaces computed from the post-shock disc, simultaneously with the equations of accretion disc along the equatorial plane. For a given spin parameter, the mass outflow rate increases as the shock moves closer to the black hole, but eventually decreases, maximizing at some intermediate value of shock location. Interestingly, we obtain all types of possible jet solutions, for example, steady shock solution with multiple critical points, bound solution with two critical points and smooth solution with single critical point. Multiple critical points may exist in jet solution for spin parameter $a_s\ge 0.5$. The jet terminal speed generally increases if the accretion shock forms closer to the horizon and is higher for corotating black hole than the counter-rotating and the non-rotating one. Quantitatively speaking, shocks in jet may form for spin parameter $a_s>0.6$ and jet shocks range between $6r_g$ and $130r_g$ above the equatorial plane, while the jet terminal speed $v_{{\rm j}\infty} > 0.35{\cm}$ if Bernoulli parameter ${\cal E}\geq1.01$ for $a_s>0.99$.
description: 22 pages, 14 figures; Accepted on May 4, 2017, for publication in MNRAS. Corrections incorporated during proof check
Letter from Paul Nash to Douglas Goldring, June 13, 1919
Creators: name: Nash, Paul, 1889-1946
Publisher: name: University of Victoria Libraries
Year: 2022
Subjects: subject: Artists
valueUri: http://id.worldcat.org/fast/817559
subject: Modernism (Literature)
valueUri: http://id.worldcat.org/fast/1024455
subject: Authors, English
valueUri: http://id.worldcat.org/fast/821945
subject: Journalists
valueUri: http://id.worldcat.org/fast/984188
subject: Literature, Modern
valueUri: http://id.worldcat.org/fast/1000172
subject: Goldring, Douglas, 1887-1960
valueUri: http://id.worldcat.org/fast/1798259
subject: Nash, Paul, 1889-1946
valueUri: http://id.worldcat.org/fast/16173
subject: Authors
valueUri: http://id.worldcat.org/fast/821688

description: Correspondence to Douglas Goldring from Paul Nash (British surrealist painter, printmaker, war artist, and older brother to Paul Nash).
Collisional parameters of planetesimal belts, precursor of debris disks, perturbed by a nearby giant planet
Creators: name: Marzari, F.
name: Dell'Oro, A.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Planetesimal belts are invoked to explain the prolonged existence of debris disks. Important parameters to model their collisional evolution and to compute the dust production rate are the intrinsic probability of collision $P_i$ and the mean impact velocity $U_c$. If a planet orbits close to the belt, the values of both these parameters are affected by its secular perturbations yielding a strong correlation between eccentricity $e$ and pericentre longitude $\varpi$. We adopt a new algorithm to compute both $P_i$ and $U_c$ in presence of various levels of secular correlation due to different ratios between proper and forced eccentricity. We tested this algorithm in a standard case with a Jupiter--sized planet orbiting inside a putative planetesimal belt finding that it is less collisionally active compared to a self--stirred belt because of the $e - \varpi$ coupling. The eccentricity of the planet is an important parameter in determining the amount of dust production since the erosion rate is 10 times faster when the planet eccentricity increases from 0.1 to 0.6. Also the initial conditions of the belt (either warm or cold) and its average inclination strongly affects $P_i$ and $U_c$ and then its long term collisional evolution in presence of the planet. We finally apply our method to the planetesimal belts supposedly refilling the dust disks around HD 38529 and $ε$ Eridani. In the most collisionally active configurations, only a small fraction of bodies smaller than 100 km are expected to be fragmented over a time--span of 4 Gyr.
description: Accepted for publication on MNRAS
Computational complexity, torsion-freeness of homoclinic Floer homology, and homoclinic Morse inequalities
Creators: name: Hohloch, Sonja
Publisher: name: arXiv
Year: 2017
Subjects: subject: Symplectic Geometry (math.SG)
subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics
subject: 20K15, 37C29, 37G20, 53D40, 57R58, 70K44

description: Floer theory was originally devised to estimate the number of 1-periodic orbits of Hamiltonian systems. In earlier works, we constructed Floer homology for homoclinic orbits on two dimensional manifolds using combinatorial techniques. In the present paper, we study theoretic aspects of computational complexity of homoclinic Floer homology. More precisely, for finding the homoclinic points and immersions that generate the homology and its boundary operator, we establish sharp upper bounds in terms of iterations of the underlying symplectomorphism. This prepares the ground for future numerical works. Although originally aimed at numerics, the above bounds provide also purely algebraic applications, namely 1) Torsion-freeness of primary homoclinic Floer homology. 2) Morse type inequalities for primary homoclinic orbits.
description: 25 pages, 7 figures; revised version (= some typos purged, a few additional explanations, figures nicer distributed throughout the article)
Wolf-Rayet spin at low metallicity and its implication for Black Hole formation channels
Creators: name: Vink, Jorick S.
name: Harries, Tim J.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The spin of Wolf-Rayet (WR) stars at low metallicity (Z) is most relevant for our understanding of gravitational wave sources such as GW 150914, as well as the incidence of long-duration gamma-ray bursts (GRBs). Two scenarios have been suggested for both phenomena: one of them involves rapid rotation and quasi-chemical homogeneous evolution (CHE), the other invokes classical evolution through mass loss in single and binary systems. WR spin rates might enable us to test these two scenarios. In order to obtain empirical constraints on black hole progenitor spin, we infer wind asymmetries in all 12 known WR stars in the Small Magellanic Cloud (SMC) at Z = 1/5 Zsun, as well as within a significantly enlarged sample of single and binary WR stars in the Large Magellanic Cloud (LMC at Z = 1/2 Zsun), tripling the sample of Vink (2007). This brings the total LMC sample to 39, making it appropriate for comparison to the Galactic sample. We measure WR wind asymmetries with VLT-FORS linear spectropolarimetry. We report the detection of new line effects in the LMC WN star BAT99-43 and the WC star BAT99-70, as well as the famous WR/LBV HD 5980 in the SMC, which might be evolving chemically homogeneously. With the previous reported line effects in the late-type WNL (Ofpe/WN9) objects BAT99-22 and BAT99-33, this brings the total LMC WR sample to 4, i.e. a frequency of ~10%. Perhaps surprisingly, the incidence of line effects amongst low-Z WR stars is not found to be any higher than amongst the Galactic WR sample, challenging the rotationally-induced CHE model. As WR mass loss is likely Z-dependent, our Magellanic Cloud line-effect WR stars may maintain their surface rotation and fulfill the basic conditions for producing long GRBs, both via the classical post-red supergiant (RSG) or luminous blue variable (LBV) channel, as well as resulting from CHE due to physics specific to very massive stars (VMS).
description: 12 pages, Accepted by Astronomy & Astrophysics
Poincaré square series for the Weil representation
Creators: name: Williams, Brandon
Publisher: name: arXiv
Year: 2017
Subjects: subject: Number Theory (math.NT)
subject: FOS: Mathematics
subject: 11F27, 11F30

description: We calculate the Jacobi Eisenstein series of weight $k \ge 3$ for a certain representation of the Jacobi group, and evaluate these at $z = 0$ to give coefficient formulas for a family of modular forms $Q_{k,m,β}$ of weight $k \ge 5/2$ for the (dual) Weil representation on an even lattice. The forms we construct always contain all cusp forms within their span. We explain how to compute the representation numbers in the coefficient formulas for $Q_{k,m,β}$ and the Eisenstein series of Bruinier and Kuss $p$-adically to get an efficient algorithm. The main application is in constructing automorphic products.
description: 30 pages. Corrected typos and other minor edits
exploreAT! - exploring Austria's culture through the language glass
Creators: name: Siemund, Melanie
name: Dorn, Amelie
name: Wandl-Vogt, Eveline
name: Theron, Roberto
name: O'Connor, Alexander
name: Kieslinger, Barbara
Publisher: name: Sci-GaIA Open Access Repository
Year: 2015

description: This poster presents a basic overview of the project exploreAT!