cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Kinetics of information scrambling in correlated electrons: disorder-driven transition from shock-wave to FKPP dynamics
Creators: name: Aron, Camille
name: Brunet, Éric
name: Mitra, Aditi
Publisher: name: arXiv
Year: 2023
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Quenched disorder slows down the scrambling of quantum information. Using a bottom-up approach, we formulate a kinetic theory of scrambling in a correlated metal near a superconducting transition, following the scrambling dynamics as the impurity scattering rate is increased. Within this framework, we rigorously show that the butterfly velocity $v$ is bounded by the light cone velocity $v_{\rm lc }$ set by the Fermi velocity. We analytically identify a disorder-driven dynamical transition occurring at small but finite disorder strength between a spreading of information characterized at late times by a discontinuous shock wave propagating at the maximum velocity $v_{\rm lc}$, and a smooth traveling wave belonging to the Fisher or Kolmogorov-Petrovsky-Piskunov (FKPP) class and propagating at a slower, if not considerably slower, velocity $v$. In the diffusive regime, we establish the relation $v^2/λ_{\rm FKPP} \sim D_{\rm el}$ where $λ_{\rm FKPP}$ is the Lyapunov exponent set by the inelastic scattering rate and $D_{\rm el}$ is the elastic diffusion constant.
description: $4+\epsilon$ pages plus 15 pages of Appendix. Minor modifications (published version)
To Clear or Not to Clear
Creators: name: Feder, Daniel
Publisher: name: Columbia Business Law Review
Year: 2019

description: In 2010, the United States Congress enacted the Dodd-Frank Wall Street Reform and Consumer Protection Act to prevent a recurrence of the 2008 financial collapse. Since its passage, the Act’s many reforms have reshaped the financial markets, but faulty executive implementation has undermined some of these components. One such issue arose in the United States Securities and Exchange Commission’s interpretation of Dodd-Frank’s Title VII central clearing mandate, which Congress included to stabilize and bring transparency to the over-the-counter derivatives market. The SEC has not yet effected mandatory clearing of security-based swaps—the financial products which Dodd-Frank subjected to the agency’s jurisdiction—but the SEC’s publicly contemplated approach omits “commission-initiated review,” a core component of Title VII’s structure. Without this type of review, many security-based swaps will remain outside the scope of mandatory central clearing, causing the SEC to fall short of its statutory mandate and Congress’ intent. This Note urges the SEC and lawmakers to take the necessary steps to address the “commission-initiated review” missing link and ensure the regulatory regime successfully includes the entire scope of financial products subject to the SEC’s jurisdiction.
description: Columbia Business Law Review, Vol. 2019 No. 1
Formule e itinerari del ‘debut-et-la fin’ nella Contemplazione della morte
Creators: name: Fabris, Angela
Publisher: name: Fondazione Università Ca’ Foscari Venezia, Italia
Year: 2021

description:

The essay proposes a selective reading of the beginnings and the endings of the four prose texts of Contemplazione della morte (1912), in their connections, according to the different typologies and functions. Attention is given to the two dedicatees, Pascoli and Bermond, together with natural landscapes and atmospheric notations, as well as to the importance given to silence and to the vitalistic image of the “cagna”, which in the finale imposes itself on that of the drowned man.

description: Archivio d’Annunzio
China as a “National Strategic Buyer”
Creators: name: Gordon, Jeffrey N.
name: Milhaupt, Curtis J.
Publisher: name: Columbia Business Law Review
Year: 2019

description: Unlike the case of cross-border trade, there is no explicit international governance regime for cross-border M&A; rather, there is a shared understanding that publicly traded companies are generally for purchase by any bidder—domestic or foreign—willing to offer a sufficiently large premium over a target’s stock market price. The unspoken premise that undergirds the system is that the prospective buyer is motivated by private economic gain-seeking. The entry of China into the global M&A market threatens the fundamental assumptions of the current permissive international regime. China has become a significant player in the cross-border M&A market, particularly as an acquirer. The central claim of the article is that the cross-border M&A regime will require a new rules-of-the-game structure to take account of China’s ascension. This is because cross-border M&A with China introduces a new dimension: what we call the “national strategic buyer” (“NSB”), whose objective is to further the interests of a nation-state in the pursuit of industrial policy or out of national security concerns. Thus, China presents a problem of asymmetric motives in the global M&A market: sellers to Chinese firms have private motives for pursuing transactions, while at least some Chinese acquirers have non-economic motivations. Yet distinguishing commercial and financial motives from national strategic motives in Chinese firms is difficult. To date, the only mechanisms for addressing the NSB problem are national security review mechanisms such as the CFIUS process in the United States, as recently expanded through legislative amendment. The EU is moving forward on a screening regulation with a similar objective that contemplates activity both by the European Commission and the Member States. Whether suitably tailored or not, these approaches fail to take on the long-term concern of fully assimilating China as a normal actor in the global economic system. To address the NSB problem, we propose the adoption of a multilateral regime under which firms subject to potential government influence in their corporate decision-making must demonstrate their “eligibility” to engage in outbound M&A. For covered firms, the regime would require a commitment to exclusively commercial/financial motives in cross-border acquisitions, made credible through a corporate governance set-up featuring independent directors (selected by foreign investors) who publicly verify adherence and disclose the source of acquisition financing. Enforcement would consist of a secretariat that can evaluate eligibility and monitor post-acquisition conduct, and national legislation that would permit rejection of an acquisition of a local target by an acquirer that does not meet the eligibility criteria.
description: Columbia Business Law Review, Vol. 2019 No. 1
A local prescription for the softening length in self-gravitating gaseous discs
Creators: name: Huré, Jean-Marc
name: Pierens, Arnaud
Publisher: name: arXiv
Year: 2009
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: In 2D-simulations of self-gravitating gaseous discs, the potential is often computed in the framework of "softened gravity" initially designed for N-body codes. In this special context, the role of the softening length LAMBDA is twofold: i) to avoid numerical singularities in the integral representation of the potential (i.e., arising when the relative separation vanishes), and ii) to acount for stratification of matter in the direction perpendicular to the disc mid-plane. So far, most studies have considered LAMBDA as a free parameter and various values or formulae have been proposed without much mathematical justification. In this paper, we demonstrate by means of a rigorous calculus that it is possible to define LAMBDA such that the gravitational potential of a flat disc coincides at order zero with that of a geometically thin disc of the same surface density. Our prescription for LAMBDA, valid in the local, axisymmetric limit, has the required properties i) and ii). It is mainly an analytical function of the radius and disc thickness, and is sensitive to the vertical stratification. For mass density profiles considered (namely, profiles expandable over even powers of the altitude), we find that LAMBDA : i) is independant of the numerical mesh, ii) is always a fraction of the local thickness H, iii) goes through a minimum at the singularity (i.e., at null separation), and iv) is such that 0.13 < LAMBDA/H < 0.29 typically (depending on the separation and on density profile). These results should help us to improve the quality of 2D- and 3D-simulations of gaseous discs in several respects (physical realism, accuracy, and computing time).
description: accepted in A&A, 7 pages, 7 figures, web link for the F90 code and on-line calculations : http://www.obs.u-bordeaux1.fr/radio/JMHure/intro2single.php
La critica del cominciamento. D'Annunzio e gli incipit giornalistici come desiderio di/del Piacere
Creators: name: Jurisic, Srecko
Publisher: name: Fondazione Università Ca’ Foscari Venezia, Italia
Year: 2021

description:

As a journalist Gabriele d'Annunzio covered the high life of the élite in the fin de siècle Rome through thousands of pages. This overwhelming and multifaceted body of work conceals aspects of d’Annunzio’s early ideological choices that can be traced in the articles. In admiring Baudelaire's Fleurs du mal and the Spleen de Paris while in the meantime he positions himself as the anti-flâneur of the umbertine Rome, d'Annunzio reveals much of his complex literary persona and the early strata of his even more layered poetics.

description: Archivio d’Annunzio
Cavity magnonics with easy-axis ferromagnet: Critically enhanced magnon squeezing and light-matter interaction
Creators: name: Lee, Jongjun M.
name: Lee, Hyun-Woo
name: Hwang, Myung-Joong
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: Generating and probing the magnon squeezing is an important challenge in the field of quantum magnonics. In this work, we propose a cavity magnonics setup with an easy-axis ferromagnet to address this challenge. To this end, we first establish a mechanism for the generation of magnon squeezing in the easy-axis ferromagnet and show that the magnon squeezing can be critically enhanced by tuning an external magnetic field near the Ising phase transition point. When the magnet is coupled to the cavity field, the effective cavity-magnon interaction becomes proportional to the magnon squeezing, allowing one to enhance the cavity-magnon coupling strength using a static field. We demonstrate that the magnon squeezing can be probed by measuring the frequency shift of the cavity field. Moreover, a magnonic superradiant phase transition can be observed in our setup by tuning the static magnetic field, overcoming the challenge that the magnetic interaction between the cavity and the magnet is typically too weak to drive the superradiant transition. Our work paves the way to develop unique capabilities of cavity magnonics that goes beyond the conventional cavity QED physics by harnessing the intrinsic property of a magnet.
description: 7+1 pages, 2+1 figures, Accepted version to Physical Review B
Unicorn Stock Options—Golden Goose or Trojan Horse?
Creators: name: Alon-Beck, Anat
Publisher: name: Columbia Business Law Review
Year: 2019

description: Large privately held startups valued at $1 billion or more (“unicorns”) are grappling with how to deal with employees’ expectations caused by the illiquidity of the shares of stock acquired upon exercise of their options. Until about eight years ago, many talented workers chose to work for a startup company for a lower cash salary combined with a substantial stock option grant and the dream of cashing out for a large sum of money after an initial public offering (“IPO”) of the startup’s stock. Today, unicorns remain private for extended periods of time, in part, because they are often no longer dependent on an IPO or a trade sale to raise sufficient capital. As a result, they are delaying liquidity events for their founders, employees, and investors, thereby causing their employee stock options to lose some of their allure as a hiring and retention device. This Article examines a contemporary puzzle in Silicon Valley: Is there a shift in unicorn employees’ expectations that results in labor contract renegotiations? To answer this question, this Article explores the challenges faced by unicorn firms as repeat players in competitive technology markets and offers the following possible solutions. First, it proposes new equity-based compensation contracts, and critiques them. Second, it suggests alternatives to the traditional liquidity mechanisms, and critiques them. Unfortunately, current securities and tax laws create legal barriers to private ordering, which prevent the parties from solving these issues on their own. This Article concludes with proposals to remove these legal barriers to private ordering to allow for the proposed solutions to take hold, accompanied with new mandatory disclosure requirements to limit the risks.
description: Columbia Business Law Review, Vol. 2019 No. 1
Theory of carrier transport in bilayer graphene
Creators: name: Sarma, S. Das
name: Hwang, E. H.
name: Rossi, E.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We develop a theory for density, disorder, and temperature dependent electrical conductivity of bilayer graphene in the presence of long-range charged impurity scattering as well as an additional short-range disorder of independent origin, establishing that both scattering mechanisms contribute significantly to determining bilayer transport properties. We find that although strong screening properties of bilayer graphene lead to qualitative differences with the corresponding single layer situation, both systems exhibit the linearly density dependent conductivity at high density and the minimum graphene conductivity behavior around the charge neutrality point due to the formation of inhomogeneous electron-hole puddles induced by the random charged impurity centers.
description: 5 pages, 4 figures
Constraints on the nonuniversal Z^\prime couplings from B\toπK, πK^{\ast} and ρK Decays
Creators: name: Chang, Qin
name: Li, Xin-Qiang
name: Yang, Ya-Dong
Publisher: name: arXiv
Year: 2009
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Motivated by the large difference between the direct CP asymmetries $A_{CP}(B^-\to π^0 K^-)$ and $A_{CP}(\bar{B}^{0}\to π^{+} K^{-})$, we combine the up-to-date experimental information on $B\toπK$, $πK^{\ast}$ and $ρK$ decays to pursue possible solutions with the nonuniversal $Z^{\prime}$ model. Detailed analyses of the relative impacts of different types of couplings are presented in four specific cases. Numerically, we find that the new coupling parameters, $ξ^{LL}$ and $ξ^{LR}$ with a common nontrivial new weak phase $ϕ_L\sim-86^{\circ}$, which are relevant to the $Z^{\prime}$ contributions to the electroweak penguin sector $\triangle C_9$ and $\triangle C_7$, are crucial to the observed "$πK$ puzzle". Furthermore, they are found to be definitely unequal and opposite in sign. We also find that $A_{CP}(B^-\to ρ^0 K^-)$ can put a strong constraint on the new $Z^{\prime}$ couplings, which implies the $Z^{\prime}$ contributions to the coefficient of QCD penguins operator $O_3$ involving the parameter $ζ^{LL}$ required.
description: 27 pages, 6 figures. References and a note added
The Anticompetitive Effect of Vertical Most-Favored-Nation Restraints and the Error of Amex
Creators: name: Carlton, Dennis
Publisher: name: Columbia Business Law Review
Year: 2019

description: This Essay explains why the Supreme Court’s economic reasoning in its recent Ohio v. American Express Co. (“Amex”) decision is wrong. The Amex case involved the use of what are called “antisteering” restraints in which a retailer is not allowed to use a variety of tactics to steer a consumer away from using an American Express (“Amex”) card and toward using another payment mechanism. The reason why a merchant might want to do this is because the cost that the merchant incurs when a customer uses an Amex card can be higher than the cost that the merchant incurs when the customer uses either another credit card, debit card, or cash. Although not challenged in the Amex case, the Amex contractual rules also prevent a retailer from imposing a surcharge on customers who use an Amex card to reflect the higher merchant cost. It is interesting to note that some countries—such as Australia—have regulated certain credit card fees, others have forbidden credit card companies from telling merchants that they cannot surcharge, and some states in the United States—such as New York—have forbidden merchants from surcharging. Restraints on surcharging or steering are examples of restraints that Ralph Winter and I call “vertical most-favored-nation restraints,” (“vMFN”) in which one supplier tells a retailer that the retailer cannot set the retail price of its product higher than that of a rival, even if its wholesale price is higher than that of its rival. Such restraints have been the subject of some litigation already, but I expect that with the increasing use of web based platforms where such restraints are often used, litigation regarding such restraints will increase. This Article illustrates the underlying economic logic behind the anticompetitive effect of vMFNs. I then apply the reasoning to credit cards and finally, using the economic framework developed, explain the economic errors in the Court’s Amex decision. For a more detailed discussion, please see the Carlton and Winter paper referenced herein.
description: Columbia Business Law Review, Vol. 2019 No. 1
La poesia italiana del Novecento e la funzione d’Annunzio: ipotesi di lavoro
Creators: name: Verdone, Alessio
Publisher: name: Fondazione Università Ca’ Foscari Venezia, Italia
Year: 2021

description:

Gabriele d’Annunzio was frequently excluded from the generative matrix of the Italian poetical twentieth century. It is time to restore the truth free of any ideological biases. In order to do that, it is necessary to retrace the studies conducted by d’Annunzio’s successors who tried to explore different ways to reckon with his work. Studies of that kind would make it possible to hypothesise a methodology to use for a systematic investigation aimed at revealing the entity of the qualitative and quantitative impact d’Annunzio’s work has had on much of the Italian poetry. It would subsequently be possible to draft a rough analytic route to use as starting point for more substantial future investigations.

description: Archivio d’Annunzio
Classical fields method for a relativistic interacting Bose gas
Creators: name: Witkowska, Emilia
name: Ziń, Paweł
name: Gajda, Mariusz
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We formulate a classical fields method for description of relativistic interacting bosonic particles at nonzero temperatures. The method relays on the assumption that at low temperatures the Bose field can be described by a c-number function. We discuss a very important role of the cut-off momentum which divides the field into dominant classical part and a small quantum correction. We illustrate the method by studying a thermodynamics of relativistic Bose field which dynamics is governed by the Klein-Gordon equation with $λψ^4$ term responsible for interactions.
description: 12 pages, 10 figures
Le lettere di Gabriele d’Annunzio a Virginio Avi. Una corrispondenza politica
Creators: name: Favia, Roberta
Publisher: name: Fondazione Università Ca’ Foscari Venezia, Italia
Year: 2021

description:

The Tursi Fund, kept at the Cini Foundation and the Marciana Library in Venice, largely unpublished, preserves an important and unexplored heritage referring to the ‘Venetian period’ of d’Annunzio and to the political and military commitment in aviation during the first world conflict. The essay presents an integral and chronologically reconstruction of the entire collection with particular attention to the letters sent by d’Annunzio to Virginio Avi, director of the Gazzetta di Venezia between 1916 and 1918.

description: Archivio d’Annunzio
Giordano Bruno Guerri. Da Ovidio a d'Annunzio. Miti di metamorfosi e metamorfosi dei miti
Creators: name: Giacon, Maria Rosa
Publisher: name: Fondazione Università Ca’ Foscari Venezia, Italia
Year: 2021

description:

Guerri, G.B. (a cura di) (2019). Da Ovidio a d'Annunzio. Miti di metamorfosi e metamorfosi dei miti = Atti del convegno di studi (Gardone Riviera, 12 ottobre 2018). Introduzione di Giordano Bruno Guerri. Cinisello Balsamo (MI): Silvana Editoriale, 128 pp.

description: Archivio d’Annunzio
A Control Approach for Human-Robot Ergonomic Payload Lifting
Creators: name: Rapetti, Lorenzo
name: Sartore, Carlotta
name: Elobaid, Mohamed
name: Tirupachuri, Yeshasvi
name: Draicchio, Francesco
name: Kawakami, Tomohiro
name: Yoshiike, Takahide
name: Pucci, Daniele
Publisher: name: arXiv
Year: 2023
Subjects: subject: Robotics (cs.RO)
subject: FOS: Computer and information sciences

description: Collaborative robots can relief human operators from excessive efforts during payload lifting activities. Modelling the human partner allows the design of safe and efficient collaborative strategies. In this paper, we present a control approach for human-robot collaboration based on human monitoring through whole-body wearable sensors, and interaction modelling through coupled rigid-body dynamics. Moreover, a trajectory advancement strategy is proposed, allowing for online adaptation of the robot trajectory depending on the human motion. The resulting framework allows us to perform payload lifting tasks, taking into account the ergonomic requirements of the agents. Validation has been performed in an experimental scenario using the iCub3 humanoid robot and a human subject sensorized with the iFeel wearable system.
Platforms and the Rule of Reason
Creators: name: Hovenkamp, Herbert
Publisher: name: Columbia Business Law Review
Year: 2019

description: This Article considers how antitrust’s rule of reason should be applied to an exclusionary practice on a platform market. It considers the rule of reason’s basic burden-shifting framework, unique elements of market delineation on platform markets and the relevance of placing production complements into the same “market.” It also considers the Court’s regressive, antieconomic conclusion on a proposition that was never briefed—whether a market definition is necessary in an antitrust challenge to a vertical practice. Then it considers the Court’s odd treatment of free rider problems. It also faults the Court for paying so little attention to the record, its lack of economic analysis, and in particular its confusion of total with marginal harms and benefits. Finally, it looks at the implications of the Court’s decision for market delineation in cases involving platforms.
description: Columbia Business Law Review, Vol. 2019 No. 1
Amex in Context
Creators: name: Rooney, William H.
name: Fleming, Timothy G.
name: Swaminathan, Sruti
Publisher: name: Columbia Business Law Review
Year: 2019

description: In his 1911 State of the Union address, President William Howard Taft, the former and future jurist, discussed the development of antitrust law since the Sherman Act’s passage: “Slowly the mills of the courts ground, and only gradually did the majesty of the law assert itself.” While Taft allowed for the possibility that some changes to the law may be beneficial, he also argued that the “object” of the Act was “near achievement,” and spoke against those calling to “abandon this work of twenty years and try another experiment[.]” Ultimately, the experiment was not abandoned, and the Sherman Act remains at the center of antitrust law in the United States. Meanwhile, the “mills of the courts” have continued to grind away. Various judges, justices—including the eventual Chief Justice Taft himself—and scholars have shaped the contours of antitrust law. One area of ongoing development is the organic rule of reason, which Taft played no small role in originating. The rule of reason was first articulated in United States v. Addyston Pipe & Steel Co.5 in 1898 and played an important role, not long after, in the titanic cases of Standard Oil of New Jersey v. United States6 and United States v. American Tobacco Co. During Taft’s presidency, however, the Supreme Court held that vertically imposed price restraints were per se illegal, and, over the decades that followed, the rule of reason began to wither and was gradually replaced, in significant part, by a series of per se rules.
description: Columbia Business Law Review, Vol. 2019 No. 1
Are Einstein-Dirac-Maxwell wormholes traversable?
Creators: name: Kain, Ben
Publisher: name: arXiv
Year: 2023
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Einstein-Dirac-Maxwell wormholes are asymptotically flat static wormhole solutions in general relativity that do not make use of exotic matter. The asymmetric static solutions are smooth, are regular everywhere, and violate the null energy condition, which suggests that they are traversable. To determine if in fact they are traversable, we numerically evolve the static solutions forward in time. In all cases considered, our simulations indicate that black holes form that are connected by the wormhole. Although there exist null geodesics that travel through the wormhole, we find that they are trapped inside a black hole and are unable to travel arbitrarily far away. We conclude that Einstein-Dirac-Maxwell wormholes are not traversable.
description: 17 pages, 8 figures; v2: typos corrected
Biotech Crowdfunding
Creators: name: Wu, Erica
Publisher: name: Columbia Business Law Review
Year: 2019

description: Equity crowdfunding, the issuance of securities through online platforms to an unlimited number of investors, became a new legal source of capital for companies beginning in May 2016. Crowdfunding is one of several methods enacted by the JOBS Act through which emerging companies, or startups, can better access public capital. However, crowdfunding presents new risks to investors as many of the traditional securities law safeguards that protect investors are reduced or removed. Particularly in the biotech sector, crowdfunding investors are subject to increased information asymmetry, as ordinary individuals investing in complex scientific technologies may lack not only information about the company and the entrepreneur, but also the scientific background necessary to fully evaluate the technology itself. This Noe analyzes the impact of the JOBS Act on biotech investing, focusing on the risks and protections available to crowdfunding investors, within as well as outside the bounds of the securities laws. This Note concludes with a proposal to integrate protections from FDA regulations and patent laws into the crowdfunding rules.
description: Columbia Business Law Review, Vol. 2018 No. 3
Gabriele d’Annunzio. Francesca da Rimini, a cura di Donato Pirovano
Creators: name: Puppa, Paolo
Publisher: name: Fondazione Università Ca’ Foscari Venezia, Italia
Year: 2021

description:

D’Annunzio, G. (2018). Francesca da Rimini. A cura di D. Pirovano. Roma: Salerno editrice, 280 pp.

description: Archivio d’Annunzio
Berry Curvature and Topological Hall Effect in Magnetic Nanoparticles
Creators: name: Ullah, Ahsan
name: Balasubramanian, Balamurugan
name: Tiwari, Bibek
name: Giri, Bharat
name: Sellmyer, David J.
name: Skomski, Ralph
name: Xu, Xiaoshan
Publisher: name: arXiv
Year: 2023
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Analytical calculations and micromagnetic simulations are used to determine the Berry curvature and topological Hall effect (THE) due to conduction electrons in small ferromagnetic particles. Our focus is on small particles of nonellipsoidal shapes, where noncoplanar spin structures yield a nonzero topological Hall signal quantified by the skyrmion number Q. We consider two mechanisms leading to noncoplanarity in aligned nanoparticles, namely flower-state spin configurations due to stray fields near corners and edges, and curling-type magnetostatic selfinteractions. In very small particles, the reverse magnetic fields enhance Q due to the flower state until the reversal occurs, whereas for particles with a radius greater than coherence radius Rcoh the Q jumps to a larger value at the nucleation field representing the transition from the flower state to the curling state. We calculate the Skyrmion density (average Berry curvature) from these spin structures as a function of particle size and applied magnetic field. Our simulation results agree with analytical calculations for both flower state and flux closure states. We showed the presence of Berry curvature in small particles as long as the size of the particle is less than the single domain limit. Using magnetic force microscopy (MFM), we also showed that in a nanodot of Co with a suitable size, a magnetic vortex state with perpendicular (turned-up) magnetization at the core is realized which can be manifested for Berry curvature and emergent magnetic field in confined geometries for single domain state at room temperature.
Role of triaxiality in the ground state shape of neutron rich Yb, Hf, W, Os, and Pt isotopes
Creators: name: Robledo, L M
name: Rodriguez-Guzman, R
name: Sarriguren, P
Publisher: name: arXiv
Year: 2009
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: The evolution of the ground-state shape along the triaxial landscape of several isotopes of Yb, Hf, W, Os, and Pt is analyzed using the self-consistent Hartree-Fock-Bogoliubov approximation. Two well reputed interactions (Gogny D1S and Skyrme SLy4) have been used in the study in order to asses to which extent the results are independent of the details of the effective interaction. A large number of even-even nuclei, with neutron numbers from N=110 up to N=122 has been considered, covering in this way a vast extension of the nuclear landscape where signatures of oblate-prolate shape transitions have already manifested both theoretically and experimentally.
description: 21 pages, 8 figures
Linear Two-Dimensional MHD of Accretion Disks: Crystalline structure and Nernst coefficient
Creators: name: Montani, Giovanni
name: Benini, Riccardo
Publisher: name: arXiv
Year: 2009
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: We analyse the two-dimensional MHD configurations characterising the steady state of the accretion disk on a highly magnetised neutron star. The model we describe has a local character and represents the extension of the crystalline structure outlined in Coppi (2005), dealing with a local model too, when a specific accretion rate is taken into account. We limit our attention to the linearised MHD formulation of the electromagnetic back-reaction characterising the equilibrium, by fixing the structure of the radial, vertical and azimuthal profiles. Since we deal with toroidal currents only, the consistency of the model is ensured by the presence of a small collisional effect, phenomenologically described by a non-zero constant Nernst coefficient (thermal power of the plasma). Such an effect provides a proper balance of the electron force equation via non zero temperature gradients, related directly to the radial and vertical velocity components. We show that the obtained profile has the typical oscillating feature of the crystalline structure, reconciled with the presence of viscosity, associated to the differential rotation of the disk, and with a net accretion rate. In fact, we provide a direct relation between the electromagnetic reaction of the disk and the (no longer zero) increasing of its mass per unit time. The radial accretion component of the velocity results to be few orders of magnitude below the equatorial sound velocity. Its oscillating-like character does not allow a real matter in-fall to the central object (an effect to be searched into non-linear MHD corrections), but it accounts for the out-coming of steady fluxes, favourable to the ring-like morphology of the disk.
description: 15 pages, 1 figure, accepted for publication on Modern Physics Letters A
Lattice QCD Analysis for Gluons
Creators: name: Suganuma, Hideo
name: Iritani, Takumi
name: Yamamoto, Arata
name: Iida, Hideaki
Publisher: name: arXiv
Year: 2009
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences

description: Nonperturbative properties of gluons are studied in SU(3) lattice QCD at the quenched level. The first subject is a functional-form analysis of the gluon propagator $D_{μν}^{ab}(x)$ in the Landau gauge. We find that the gluon propagator $D_{μμ}^{aa}(r)$ obtained in lattice QCD is well described by the four-dimensional (4D) Yukawa-type function $e^{-mr}/r$ with $m \simeq 600$MeV for the Euclidean 4D distance $r = 0.1 \sim 1.0$ fm. In momentum space, the gluon propagator $\tilde D_{μμ}^{aa}(p^2)$ ($p= 0.5 \sim 3$ GeV) is found to be well approximated with a new-type propagator of $(p^2+m^2)^{-3/2}$, which corresponds to 4D Fourier image of the Yukawa-type function. Associated with the Yukawa-type gluon propagator, we derive analytical expressions for the zero-spatial-momentum propagator $D_0(t)$, the effective mass $M_{\rm eff}(t)$, and the spectral function $ρ(ω)$ of the gluon field. The mass parameter $m$ turns out to be the infrared effective mass of gluons. The obtained gluon spectral function $ρ(ω)$ is almost negative-definite for $ω>m$, except for a positive $δ$-functional peak at $ω=m$. The second subject is a lattice-QCD determination of the relevant gluonic momentum-component for color confinement. As a remarkable fact, the string tension is found to be almost unchanged even after cutting off the high-momentum gluon component above 1.5 GeV in the Landau gauge. In fact, the relevant gluonic scale for color confinement is concluded to be below 1.5 GeV.
description: Invited talk at International Workshop on QCD Green's Functions, Confinement, and Phenomenology - QCD-TNT09, September 07 - 11 2009, ECT Trento, Italy
Move Last and Take Things
Creators: name: Obear, Josh
Publisher: name: Columbia Business Law Review
Year: 2019

description: Facebook’s now decade-long dominance of the social media landscape stands in start contrast with the industry’s early history of dynamism and disruption. The company played a key role in growing the social media industry from the small, niche communities of the early 2000s into the omnipresent societal force it is today. Capitalizing on this growth, Facebook pioneered a business model that now transforms the attention of billions of users into billions of dollars of advertising revenue. But for all of Facebook’s success, perhaps its greatest triumph has been in defending its golden goose from a swarm of competitors eager to claim a share of the profits. Countless challenges from Snapchat, Twitter, Google, and dozens of social network startups have all failed to break Facebook’s hold of the market. This Note argues that Facebook has exploited its market dominance to exclude competitors in the social media market. Despite complaints from competitors and business commentators, Facebook has so far avoided serious antitrust inquiry. By examining Facebook’s history, its business model, and the structural incentives of the social media market, one can see how Facebook leverages its position toward anticompetitive ends. In particular, this Note explores how Facebook copies the popular apps and features developed by its rivals in order to prevent those rivals from establishing a foothold in the social media market. This copycat strategy causes significant non-monetary consumer harms, such as product degradation and stifled innovation, currently neglected by antitrust doctrine. Facebook’s copying campaign highlights the need for courts o consider new frameworks and theories that help identify new forms of anticompetitive conduct.
description: Columbia Business Law Review, Vol. 2018 No. 3
Cooling a micro-mechanical resonator by quantum back-action from a noisy qubit
Creators: name: Wang, Ying-Dan
name: Li, Yong
name: Xue, Fei
name: Bruder, C.
name: Semba, K.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We study the role of qubit dephasing in cooling a mechanical resonator by quantum back-action. With a superconducting flux qubit as a specific example, we show that ground-state cooling of a mechanical resonator can only be realized if the qubit dephasing rate is sufficiently low.
description: 5 pages, 3 figures
Gabriele d’Annunzio. Studi su Gesù. Appunti, Taccuini, Parabole, a cura di Angelo Piero Cappello
Creators: name: Gibellini, Pietro
Publisher: name: Fondazione Università Ca’ Foscari Venezia, Italia
Year: 2021

description:

Cappello, A.P. (a cura di) (2021). Gabriele d’Annunzio: Studi su Gesù. Appunti, Taccuini, Parabole. Prefazione di G.B. Guerri. Pescara: Ianieri, 280 pp.

description: Archivio d’Annunzio
Giulio Aristide Sartorio, Il ritorno di Raffaello
Creators: name: Trevisan, Alessandra
Publisher: name: Fondazione Università Ca’ Foscari Venezia, Italia
Year: 2021

description:

Gibellini, C. (a cura di) (2020). Giulio Aristide Sartorio: Il ritorno di Raffaello. Milano: Medusa, 344 pp.

description: Archivio d’Annunzio
Hacking Our Securities Disclosure System
Creators: name: Auman, Jason
Publisher: name: Columbia Business Law Review
Year: 2019

description: Broker-dealers provide investors with the platform to access security markets. To facilitate this access, clients entrust them with sensitive information, including their names, addresses, and social security numbers. Cyberattacks on the financial sector have advances in sophistication and grown more frequent due to technological advances, adjustments in firm business models, and changes in customer behavior, causing new vulnerabilities in firm information systems. However, even with this increase of cyberattacks against broker-dealers, the lack of public disclosure requirements means little is known about the extent of broker-dealer cyber safety. Under current SEC regulations, broker-dealers must take preventative action, such as establishing safeguards against cyber breached and maintaining security programs that can identify red flags. However, after a cyberattack occurs, firms are only required to file a Suspicious Activity Report to FinCEN, a bureau within the Treasury Department. Unlike public companies and banks, broker-dealers do not have any federal disclosure requirement to the general public for cybersecurity incidents. Addressing this gap requires a comprehensive examination of the tradeoffs involved in implementing broad new federal disclosure requirements for broker-dealers following cybersecurity incidents.
description: Columbia Business Law Review, Vol. 2018 No. 3
FoPro-KD: Fourier Prompted Effective Knowledge Distillation for Long-Tailed Medical Image Recognition
Creators: name: Elbatel, Marawan
name: Martí, Robert
name: Li, Xiaomeng
Publisher: name: arXiv
Year: 2023
Subjects: subject: Image and Video Processing (eess.IV)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Machine Learning (cs.LG)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: Representational transfer from publicly available models is a promising technique for improving medical image classification, especially in long-tailed datasets with rare diseases. However, existing methods often overlook the frequency-dependent behavior of these models, thereby limiting their effectiveness in transferring representations and generalizations to rare diseases. In this paper, we propose FoPro-KD, a novel framework that leverages the power of frequency patterns learned from frozen pre-trained models to enhance their transferability and compression, presenting a few unique insights: 1) We demonstrate that leveraging representations from publicly available pre-trained models can substantially improve performance, specifically for rare classes, even when utilizing representations from a smaller pre-trained model. 2) We observe that pre-trained models exhibit frequency preferences, which we explore using our proposed Fourier Prompt Generator (FPG), allowing us to manipulate specific frequencies in the input image, enhancing the discriminative representational transfer. 3) By amplifying or diminishing these frequencies in the input image, we enable Effective Knowledge Distillation (EKD). EKD facilitates the transfer of knowledge from pre-trained models to smaller models. Through extensive experiments in long-tailed gastrointestinal image recognition and skin lesion classification, where rare diseases are prevalent, our FoPro-KD framework outperforms existing methods, enabling more accessible medical models for rare disease classification. Code is available at https://github.com/xmed-lab/FoPro-KD.
description: Accepted at IEEE TMI, code is available at https://github.com/xmed-lab/FoPro-KD
Sunrise, Sunset
Creators: name: Winden, Andrew
Publisher: name: Columbia Business Law Review
Year: 2019

description: A battle is brewing for control of America’s most dynamic companies. Entrepreneurs are increasingly seeking protection from interference or dismissal by public investors through the adoption of dual-class stock structures in initial public offerings. Institutional investors are pushing back, demanding that sucks structures be abandoned or strictly limited through subset provisions. The actual terms of dual-class stock structures, however, have been remarkably understudied, so the debate between proponents of prohibition and private ordering is ill-informed. This paper presents the first empirical analysis of the initial, or sunrise, and terminal, or sunset, provisions found in the charters of dual-class companies, with a data set of 139 U.S. pubic companies. Careful selection of such provisions can satisfy both the desire of entrepreneurs to pursue their idiosyncratic visions for value creation without fear of interference or dismissal and the need of investors for a voice to ensure management accountability. Private law firms representing entrepreneurs in initial public offerings play a critical role in the selection of charter provisions, so the onus is on such firms to ensure that private ordering produces a satisfactory resolution before momentum builds for a regulatory solution to investors’ concerns.
description: Columbia Business Law Review, Vol. 2018 No. 3
Light-cone Distribution Amplitudes of Xi and their Applications
Creators: name: Liu, Yong-Lu
name: Huang, Ming-Qiu
Publisher: name: arXiv
Year: 2009
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We present the light-cone distribution amplitudes of the Xi baryons up to twist six on the basis of QCD conformal partial wave expansion to the leading order conformal spin accuracy. The nonperturbative parameters relevant to the DAs are determined in the framework of the QCD sum rule. The light-cone QCD sum rule approach is used to investigate both the electromagnetic form factors of Xi and the exclusive semileptonic decay of Xi_c as applications. Our estimations on the magnetic moments are $μ_{Ξ^0}=-(1.92\pm0.34)μ_N$ and $μ_{Ξ^-}=-(1.19\pm0.03)μ_N$. The decay width of the process Xi_c->Xi e^+ν_e is evaluated to be $Γ=8.73\times10^{-14}{GeV}$, which is in accordance with the experimental measurements and other theoretical approaches.
description: 23 pages, 8 figures, version to appear in Phys. Rev. D
L’oubli et ses enjeux dans les littératures africaine et antillaise
Creators: name: Akinwumi, Joel
Publisher: name: University of British Columbia
Year: 2023

description: By analyzing six postcolonial African and Caribbean novels written by Léonora Miano, Tierno Monénembo, Marie-Célie Agnant, Henri Lopes, Simone Schwarz-Bart and Patrick Chamoiseau, this dissertation unravels the protean nature, operation, and socio-cultural implications of forgetting in connection with the representation of the historical phenomena of the past, key among which are the Middle Passage, Transatlantic Slave Trade and Colonialism. Critical attention is paid to how forgetting derives from discursive practices and subtly imposed political and insidious ideologies. As an inevitable force, forgetting is often construed as the obverse face of memory and consequently as a kind of amnesia or dysfunction. Breaking away from this postulation, my research demonstrates that forgetting is not just a denial of memory but a peculiar modality of processing traumatic historical experiences. Secondly, leaning on theorists such as Paul Ricœur, Édouard Glissant, Edward S. Casey, and Tzvetan Todorov, I argue that forgetting needs to be nuanced in the light of the exigencies of the moment and that, more than a mere contestation of History, frictions around it touch on issues of gender norms, identity politics, race, marginality, agency, and utopianism. Thirdly, I conclude that forgetting functions as a matrix of literary creativity and expression free from the reductionist schematic divisions that have impinged on the relationship between the colonized African and Caribbean and their Western counterparts. To be sure, this research deepens our insight into the workings of forgetting from a literary standpoint and helps us to grasp more clearly how the equilibrium between memory and forgetting is attained.
Theory of free fermions under random projective measurements
Creators: name: Poboiko, Igor
name: Pöpperl, Paul
name: Gornyi, Igor V.
name: Mirlin, Alexander D.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: We develop an analytical approach to the study of one-dimensional free fermions subject to random projective measurements of local site occupation numbers, based on the Keldysh path-integral formalism and replica trick. In the limit of rare measurements, $γ/ J \ll 1$ (where $γ$ is measurement rate per site and $J$ is hopping constant in the tight-binding model), we derive a non-linear sigma model (NLSM) as an effective field theory of the problem. Its replica-symmetric sector is described by a $U(2) / U(1) \times U(1) \simeq S_2$ sigma model with diffusive behavior, and the replica-asymmetric sector is a two-dimensional NLSM defined on $SU(R)$ manifold with the replica limit $R \to 1$. On the Gaussian level, valid in the limit $γ/ J \to 0$, this model predicts a logarithmic behavior for the second cumulant of number of particles in a subsystem and for the entanglement entropy. However, the one-loop renormalization group analysis allows us to demonstrate that this logarithmic growth saturates at a finite value $\sim (J / γ)^2$ even for rare measurements, which corresponds to the area-law phase. This implies the absence of a measurement-induced entanglement phase transition for free fermions. The crossover between logarithmic growth and saturation, however, happens at exponentially large scale, $\ln l_\text{corr} \sim J / γ$. This makes this crossover very sharp as a function of the measurement frequency $γ/ J$, which can be easily confused with a transition from the logarithmic to area law in finite-size numerical calculations. We have performed a careful numerical analysis, which supports our analytical predictions.
description: 24 pages, 5 figures