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We consider the forces acting on electrons in magnetic field including the constraints and a condition arising from quantum mechanics. The force is calculated as the electron mass, $m_e$, multiplied by the total time-derivative of the velocity field evaluated using the quantum mechanical many-electron wave function. The velocity field includes a term of the Berry connection from the many-body wave function; thereby, quantum mechanical effects are included. It is shown that additional important forces besides the Lorentz force exist; they include the gradient of the electron velocity field kinetic energy, the gradient of the chemical potential, and the `force' for producing topologically protected loop currents. These additional forces are shown to be important in superconductivity, electric current in metallic wires, and charging of capacitors.
Differential privacy (DP), as a promising privacy-preserving model, has attracted great interest from researchers in recent years. Currently, the study on combination of machine learning and DP is vibrant. In contrast, another widely used artificial intelligence technique, the swarm intelligence (SI) algorithm, has received little attention in the context of DP even though it also triggers privacy concerns. For this reason, this paper attempts to combine DP and SI for the first time, and proposes a general differentially private swarm intelligence algorithm framework (DPSIAF). Based on the exponential mechanism, this framework can easily develop existing SI algorithms into the private versions. As examples, we apply the proposed DPSIAF to four popular SI algorithms, and corresponding analyses demonstrate its effectiveness. More interestingly, the experimental results show that, for our private algorithms, their performance is not strictly affected by the privacy budget, and one of the private algorithms even owns better performance than its non-private version in some cases. These findings are different from the conventional cognition, which indicates the uniqueness of SI with DP.
We derive an analytic formula for the Young's modulus in single-layer black phosphorus using the valence force field model. By analyzing the directional dependence for the Young's modulus, we explore the third principle direction with direction angle phi_tp = 0.268pi besides armchair and zigzag directions. The maximum Young's modulus value is in the third principle direction. More specifically, the Young's modulus is 52.2 N/m, 85.4 N/m, and 111.4 N/m in the armchair direction, zigzag direction, and the third principle direction, respectively. This new principle direction is of significance for future discussions of other anisotropic properties in the single-layer black phosphorus.
We propose a new metric space of ReLU activation codes equipped with a truncated Hamming distance which establishes an isometry between its elements and polyhedral bodies in the input space which have recently been shown to be strongly related to safety, robustness, and confidence. This isometry allows the efficient computation of adjacency relations between the polyhedral bodies. Experiments on MNIST and CIFAR-10 indicate that information besides accuracy might be stored in the code space.
In this talk I address the theoretical issue of what new physics is required to make $m_ν eq 0$. I then discuss what other things may happen besides neutrino oscillations. In particular I consider a possible new scenario of leptogenesis in R parity nonconserving supersymmetry.
Current theoretical approaches to manganites mainly stem from magnetic framework, in which the electronic transport is thought to be spin-dependent and the double exchange mechanism plays a core role. However, quite a number of experimental observations can yet not be reasonably explained. For example, multiplicate insulator-metal transitions and resistivity reduction induced by perturbations other than magnetic field, such as electric current, are not well understood. A comprehensive analysis on earlier extensive studies is performed and two types of origins for resistivity change are highlighted. Besides the insulated-to-metallic transition induced by external field such as magnetic field, the insulated-to-insulated transition induced extrinsically is even a more important source for the colossal resistivity change. We propose an extended framework for the electronic transport of manganites, in which the contribution of charge degree of freedom is given a special priority.
Thimble regularization as a solution to the sign problem has been successfully put at work for a few toy models. Given the non trivial nature of the method (also from the algorithmic point of view) it is compelling to provide evidence that it works for realistic models. A Chiral Random Matrix theory has been studied in detail. The known analytical solution shows that the model is non-trivial as for the sign problem (in particular, phase quenched results can be very far away from the exact solution). This study gave us the chance to address a couple of key issues: how many thimbles contribute to the solution of a realistic problem? Can one devise algorithms which are robust as for staying on the correct manifold? The obvious step forward consists of applications to gauge theories.
I review ongoing efforts to understand the incidence of magnetism in intermediate-mass stars that are different from the magnetic Ap stars. This includes the search for magnetic fields in chemically peculiar stars of the Am and HgMn types as well as in normal A and late-B stars. I discuss different techniques for detection of weak stellar magnetic fields and present a critical evaluation of the recent magnetic detections in non-Ap stars. Special attention is given to the magnetic status of HgMn stars and to the discovery of weak polarization signatures in Sirius and Vega.
We present observations of CK Vul obtained with the Spitzer Space Telescope. The infrared spectrum reveals a warm dust continuum with nebular, molecular hydrogen and HCN lines superimposed, together with the "Unidentified Infrared" (UIR) features. The nebular lines are consistent with emission by a low density gas. We conclude that the Spitzer data, combined with other information, are incompatible with CK Vul being a classical nova remnant in "hibernation" after the event of 1670, a "Very Late Thermal Pulse", a "Luminous Red Variable" such as V838 Mon, or a "Diffusion-induced nova". The true nature of CK Vul remains a mystery.
In this study, Si and C were incorporated into polycrystalline MgB2 via in situ reaction of Mg and B with either SiC or with separate Si and C (Si+C). The electrical transport and magnetic properties of the two series of samples were compared. The corrected resistivity at 40K, Rho A(40K), is higher for the SiC reacted samples regardless of carbon (C) substitution level, indicating larger intragrain scattering because of the simultaneous reaction between Mg and SiC and carbon substitution during the formation of MgB2. In addition, because of the cleaner reaction route for the SiC reacted samples, the calculated active area that carries current, AF, is twice that of the (Si+C) samples. On the other hand, the upper critical field, Hc2, was similar for both sets of samples despite their different C substitution levels which proves the importance of defect scattering in addition to C substitution level. Hence, the form of the precursor reactants is critical for tuning the form of Hc2(T).
Ultra High Energy Cosmic Rays, UHECR, maybe protons, as most still believe and claim, or nuclei; in particular lightest nuclei as we advocated recently. The first (Auger Collaboration) nucleon proposal (2007)[2] foresaw to trace clearly the UHECR GZK Universe reaching far (up to 100 Mpc) Super-Galactic-Plane, with little angular dispersion. On the contrary Lightest Nuclei model (2008)[3], inspired by observed composition and by nearest CenA clustering (almost a quarter of the AUGER events) explains a modest and narrow (few Mpc) Universe view, as well as the puzzling Virgo absence: lightest nuclei offer a fragile (and therefore very nearby) blurred Astronomy. Here we address to a part of the remaining scattered events in the new up-dated Auger map (March 2009-ICRC09). We found within rarest clustering the surprising imprint of a few galactic sources, a partial component of UHECR sources. In particular we recognize a first trace of Vela, brightest gamma and radio galactic source, and smeared sources along Galactic Plane and Center. The clustering may imply additional tails of fragments (by nuclei photo-dissociation) at half energies. The UHECR light-nuclei fragility and opacity may a
Classifying legal documents is a challenge, besides their specialized vocabulary, sometimes they can be very long. This means that feeding full documents to a Transformers-based models for classification might be impossible, expensive or slow. Thus, we present a legal document classifier based on DeBERTa V3 and a LSTM, that uses as input a collection of 48 randomly-selected short chunks (max 128 tokens). Besides, we present its deployment pipeline using Temporal, a durable execution solution, which allow us to have a reliable and robust processing workflow. The best model had a weighted F-score of 0.898, while the pipeline running on CPU had a processing median time of 498 seconds per 100 files.
We study a model of a nonrenewable resource market, e.g. crude oil market. This market consists of a cartel with market power and a fringe consisting of many small firms, whose deposits are interrelated. In addition, the firms face constraints on extraction. Besides the nonrenewable resource, there is also its sustainable substitute, which constrains the price. We fully characterize the resulting Stackelberg equilibrium. Besides typical solution, in which initially the cartel and fringe extract simultaneously, we find that for some model parameters and initial capacities, the cartel may also deter the fringe from extraction, or it may refrain from extraction until the fringe depletes their deposit. We conduct sensitivity analysis and study the conditions when one of those counterintuitive solutions is optimal.
Continuum-type constitutive relations of odd matter need to be formulated according to the second law of thermodynamics. Based on the primitive thermodynamics of Edelen, a procedure admitting most general relations, is outlined for heat-conducting fluids and solids. For viscous responses of odd matter, the theory accounts for the irreversible and non-dissipative forces, besides the hyperdissipative ones. For quasi-static responses, the theory grasps the elastic and non-conservative forces besides those derivable from the free energy, this being the realm of Cauchy elasticity beyond hyperelasticity. In Cosserat-type odd matter, primitive thermodynamics also accounts for curvature-torsion and couple-stress besides, respectively, deformation and force-stress tensors. In both, classical and micropolar cases, the theory grasps all possible couplings between the thermodynamic velocity and force vectors, along with a full range of anisotropies of hyperdissipative and hyperelastic responses (both linear and nonlinear).
We extend the semantics and type system of a lambda calculus equipped with common constructs to be "resource-aware". That is, the semantics keeps track of the usage of resources, and is stuck, besides in case of type errors, if either a needed resource is exhausted, or a provided resource would be wasted. In such way, the type system guarantees, besides standard soundness, that for well-typed programs there is a computation where no resource gets either exhausted or wasted. The extension is parametric on an arbitrary "grade algebra", modeling an assortment of possible usages, and does not require ad-hoc changes to the underlying language. To this end, the semantics needs to be formalized in big-step style; as a consequence, expressing and proving (resource-aware) soundness is challenging, and is achieved by applying recent techniques based on coinductive reasoning.
We prove the non-existence of new eigenvalues in $[0,Λ]$ for specific and random finite coverings of a complete and connected Riemannian manifold $M$ with Ricci curvature bounded from below, where $Λ$ is any positive number below the essential spectrum of $M$ and the spectrum of the universal cover of $M$, provided the representation theory of the fundamental group of $M$ satisfies certain conditions.
Facial sketch synthesis (FSS) aims to generate a vivid sketch portrait from a given facial photo. Existing FSS methods merely rely on 2D representations of facial semantic or appearance. However, professional human artists usually use outlines or shadings to covey 3D geometry. Thus facial 3D geometry (e.g. depth map) is extremely important for FSS. Besides, different artists may use diverse drawing techniques and create multiple styles of sketches; but the style is globally consistent in a sketch. Inspired by such observations, in this paper, we propose a novel Human-Inspired Dynamic Adaptation (HIDA) method. Specially, we propose to dynamically modulate neuron activations based on a joint consideration of both facial 3D geometry and 2D appearance, as well as globally consistent style control. Besides, we use deformable convolutions at coarse-scales to align deep features, for generating abstract and distinct outlines. Experiments show that HIDA can generate high-quality sketches in multiple styles, and significantly outperforms previous methods, over a large range of challenging faces. Besides, HIDA allows precise style control of the synthesized sketch, and generalizes well to na
Besides natural language processing, transformers exhibit extraordinary performance in solving broader applications, including scientific computing and computer vision. Previous works try to explain this from the expressive power and capability perspectives that standard transformers are capable of performing some algorithms. To empower transformers with algorithmic capabilities and motivated by the recently proposed looped transformer, we design a novel transformer framework, dubbed Algorithm Transformer (abbreviated as AlgoFormer). We provide an insight that efficient transformer architectures can be designed by leveraging prior knowledge of tasks and the underlying structure of potential algorithms. Compared with the standard transformer and vanilla looped transformer, the proposed AlgoFormer can perform efficiently in algorithm representation in some specific tasks. In particular, inspired by the structure of human-designed learning algorithms, our transformer framework consists of a pre-transformer that is responsible for task preprocessing, a looped transformer for iterative optimization algorithms, and a post-transformer for producing the desired results after post-processin
In this work, we develop universal quantum computing models that form a family of quantum von Neumann architecture, with modular units of memory, control, CPU, internet, besides input and output. This family contains three generations characterized by dynamical quantum resource theory, and it also circumvents no-go theorems on quantum programming and control. Besides universality, such a family satisfies other desirable engineering requirements on system and algorithm designs, such as the modularity and programmability, hence serves as a unique approach to build universal quantum computers.
Neutron stars are known to have strong magnetic fields reaching as high as $10^{15}$ Gauss, besides having strongly curved interior spacetime. So for computing an equation of state for neutron-star matter, the effect of magnetic field as well as curved spacetime should be taken into account. In this article, we compute the equation of state for an ensemble of degenerate fermions in the curved spacetime of a neutron star in presence of a magnetic field. We show that the effect of curved spacetime on the equation of state is relatively stronger than the effect of observed strengths of magnetic field. Besides, a thin layer containing only spin-up neutrons is shown to form at the boundary of a degenerate neutron star.