Top arXiv papers

• We reexamine a minimal extension of the Standard Model (SM) through the introduction of an additional $U(1)$ symmetry leading to a new neutral gauge boson ($Z'$). An SM neutral scalar is used to spontaneously break this extra symmetry leading to the mass of the $Z'$. Except for three right-handed neutrinos no other fermions are added. After a brief recapitulation, we use the current LHC Drell-Yan~(DY) data to put model independent constraints on the $Z'$ couplings. Three important unknowns here are $M_{Z'}$, the $Z$-$Z'$ mixing angle ($\alpha_z$), and the extra $U(1)$ gauge coupling ($g_x$). Treating $g_x$ as a parameter, juxtaposition of additional constraints from unitarity and low energy neutrino-electron scattering on that obtained from the direct searches allows us to extract the following limits in the gauged $(B-L)$ model: $M_{Z'} > 3.5$ TeV and $|\alpha_z| < 0.003$, when the strength of the additional $U(1)$ gauge coupling is the same as that of the SM $SU(2)_L$. For vanishing $Z$-$Z'$ mixing, the lower limit on $M_{Z'}$ goes up to 4~TeV. For some other $U(1)$ models we considered, the bounds turn out to be roughly of the same order.
• In this paper we study the Dirichlet eigenvalue problem $$-\Delta_p u-\Delta_J,pu =\lambda|u|^p-2u \quad \text in \Omega,\quad u=0 \quad\text in \Omega^c=\mathbbR^N∖\Omega.$$ Here $\Delta_p u$ is the standard local $p-$Laplacian, $\Delta_{J,p}u$ is a nonlocal, $p-$homogeneous operator of order zero and $\Omega$ is a bounded domain in $\mathbb{R}^N$. We show that the first eigenvalue (that is isolated and simple) satisfies $(\lambda_1)^{1/p}\to \Lambda$ as $p\to\infty$ where $\Lambda$ can be characterized in terms of the geometry of $\Omega$. We also find that the eigenfunctions converge, $u_\infty=\lim_{p\to\infty} u_p$, and find the limit problem that is satisfied in the limit.
• We systematically investigate heat transport of the spin-boson system near thermal equilibrium. We derive an asymptotically exact expression of thermal conductance in low temperature regime, where the transport is described by co-tunneling mechanism. This formula predicts power-law temperature dependence of thermal conductance $\propto T^{2s+1}$ for the thermal environment of spectral density with the exponent $s$. We performed accurate numerical simulation with the quantum Monte Carlo method, and confirmed these predictions for arbitrary types of thermal baths. Our accurate numerical calculation classifies transport mechanism, and shows that the noninteracting-blip approximation quantitatively describe thermal conductance in the incoherent transport regime.
• Mar 22 2018 astro-ph.SR arXiv:1803.07986v1
Young open clusters are our laboratories for studying high-mass star formation and evolution. Unfortunately, the information that they provide is difficult to interpret, and sometimes contradictory. In this contribution, I present a few examples of the uncertainties that we face when confronting observations with theoretical models and our own assumptions.
• This paper considers a class of real-time decision making problems to minimize the expected value of a function that depends on a random variable $\xi$ under an unknown distribution $\mathbb{P}$. In this process, samples of $\xi$ are collected sequentially in real time, and the decisions are made, using the real-time data, to guarantee out-of-sample performance. We approach this problem in a distributionally robust optimization framework and propose a novel Online Data Assimilation Algorithm for this purpose. This algorithm guarantees the out-of-sample performance in high probability, and gradually improves the quality of the data-driven decisions by incorporating the streaming data. We show that the Online Data Assimilation Algorithm guarantees convergence under the streaming data, and a criteria for termination of the algorithm after certain number of data has been collected.
• TESS is expected to discover dozens of temperate terrestrial planets orbiting M dwarfs whose atmospheres could be followed up with the James Webb Space Telescope (JWST). Currently, the TRAPPIST-1 system serves as a benchmark to determine the feasibility and resources required to yield atmospheric constraints. We assess these questions and leverage an information content analysis to determine observing strategies for yielding high precision spectroscopy in transmission and emission. Our goal is to guide observing strategies of temperate terrestrial planets in preparation for the early JWST cycles. First, we explore JWST's current capabilities and expected spectral precision for targets near the saturation limits of specific modes. In doing so, we highlight the enhanced capabilities of high efficiency readout patterns that are being considered for implementation in Cycle 2. We propose a partial saturation strategy to increase the achievable precision of JWST's NIRSpec Prism. We show that JWST has the potential to detect the dominant absorbing gas in the atmospheres of temperate terrestrial planets by the 10th transit using transmission spectroscopy techniques in the near-IR. We also show that stacking $\gtrapprox$10 transmission spectroscopy observations is unlikely to yield significant improvements in determining atmospheric composition. For emission spectroscopy, we show that the MIRI LRS is unlikely to provide robust constraints on the atmospheric composition of temperate terrestrial planets. Higher precision emission spectroscopy at wavelengths longward of those accessible to MIRI LRS, as proposed in the Origins Space Telescope concept, could help improve the constraints on molecular abundances of temperate terrestrial planets orbiting M-dwarfs.
• The novel electronic structures can induce unique physical properties in two-dimensional (2D) materials. In this work, we report isolated highly localized bands in $\mathrm{YbI_2}$ monolayer by the first-principle calculations within generalized gradient approximation (GGA) plus spin-orbit coupling (SOC). It is found that $\mathrm{YbI_2}$ monolayer is an indirect-gap semiconductor using both GGA and GGA+SOC. The calculations reveal that Yb-$4f$ orbitals constitute isolated highly localized bands below the Fermi level at the absence of SOC, and the bands are split into the $j = 7/2$ and $j = 5/2$ states with SOC. The isolated highly localized bands can lead to very large Seebeck coefficient and very low electrical conductivity in p-type doping by producing very large effective mass of the carrier. It is proved that isolated highly localized bands have very strong stability again strain, which is very important for practical application. When the onsite Coulomb interaction is added to the Yb-$4f$ orbitals, isolated highly localized bands persist, and only their relative positions in the gap change. These findings open a new window to search for novel electronic structures in 2D materials.
• The main purpose of the present paper is to discuss whether or not the collective flows in heavy-ion collision at Fermi energy can be taken as a tool to investigate the cluster configuration in light nuclei. In practice, within an Extended Quantum Molecular Dynamics model, four $\alpha$-clustering (linear chain, kite, square, and tetrahedron) configurations of $^{16}$O are employed in the initialization, $^{16}$O+$^{16}$O around Fermi energy (40 - 60 MeV$/$nucleon) with impact parameter 1 - 3 fm are simulated, the directed and elliptic flows are analyzed. It is found that collective flows are influenced by the different $\alpha$-clustering configurations, and the directed flow of free protons is more sensitive to the initial cluster configuration than the elliptic flow. Nuclear reaction at Fermi energy can be taken a useful way to study cluster configuration in light nuclei.
• This Report summarizes the proceedings of the 2017 Les Houches workshop on Physics at TeV Colliders. Session 1 dealt with (I) new developments relevant for high precision Standard Model calculations, (II) theoretical uncertainties and dataset dependence of parton distribution functions, (III) new developments in jet substructure techniques, (IV) issues in the theoretical description of the production of Standard Model Higgs bosons and how to relate experimental measurements, (V) phenomenological studies essential for comparing LHC data from Run II with theoretical predictions and projections for future measurements, and (VI) new developments in Monte Carlo event generators.
• Let $\Omega\subset\mathbb R^{n+1}$ be an open set with $n$-AD-regular boundary. In this paper we prove that if the harmonic measure for $\Omega$ satisfies the so-called weak-$A_\infty$ condition, then $\Omega$ satisfies a suitable connectivity condition, namely the weak local John condition. This yields the first geometric characterization of the weak-$A_\infty$ condition of harmonic measure, which is important because its connection with the Dirichlet problem for the Laplace equation.
• We consider the problem of finding the isolated common roots of a set of polynomial functions defining a zero-dimensional ideal I in a ring R of polynomials over C. Normal form algorithms provide an algebraic approach to solve this problem. We use new characterizations of normal forms and describe accurate and efficient constructions that allow us to compute the algebra structure of R/I, and hence the solutions of I. We show how the resulting algorithms give accurate results in double precision arithmetic and compare with normal form algorithms using Groebner bases and homotopy solvers.
• Photon-nuclear reaction in a transport model frame, namely an Extended Quantum Molecular Dynamics (EQMD) model, has been realised at the photon energy of 70-140 MeV in the quasi-deuteron (QD) regime. For an important application, we pay a special focus on photonuclear reactions of $^{12}$C($\gamma$,np)$^{10}$B where $^{12}$C is considered as different configurations including $\alpha$-clustering. Obvious differences for some observables have been observed among different configurations, which can be attributed to spatial-momentum correlation of a neutron-proton pair inside nucleus, and therefore it gives us a sensitive probe to distinguish the different configurations including $\alpha$ clustering with the help of the photonuclear reaction mechanism.
• Periodical multilayer (ML) structures can be used as generators of X-ray standing waves (XSW) for investigation of objects and processes on solid/liquid and solid/gas interfaces. In this paper, we investigate the specific requirements to the structural properties of the multilayer structures for XSW application. We consider the effect of typical defects in the ML structure on the X-ray standing wave formation and show that the X-ray standing wave is very robust against the random imperfection in the multilayer structure. In contrast, the roughness of the topmost layer will have a strong influence on the XSW experimental results, as the ML serves as a support for the investigated objects, so that the surface geometry gets directly translated into the objects. In the experimental part of this work, we have used the ion-beam deposition to grow Ni/Al metal- and metal oxide-based multilayers and investigate with AFM their surface quality. The presented results demonstrate that metal oxides can be successfully used as basic material for X-ray multilayer standing wave generators.
• Since hydrogen fuel involves the highest energy density among all fuels, production of this gas through the solar water splitting approach has been suggested as a green remedy for greenhouse environmental issues due to extensive consumption of fossil fuels. Low dimensional materials possessing a large surface-to-volume ratio can be a promising candidate to be used for the photocatalytic approach. Here, we used extensive first principles calculations to investigate the application of newly fabricated members of two dimensional carbon nitrides including tg-C3N4, hg-C3N4, C2N, and C3N for water splitting. Band engineering via n-type, p-type, and isoelectronic doping agents such as B, N, P, Si, and Ge was demonstrated for tuning the electronic structure; optimizing solar absorption and band alignment for photocatalysis. Pristine tg-C3N4, hg-C3N4, and C2N crystals involve bandgaps of 3.190 eV, 2.772 eV, and 2.465 eV, respectively, which are not proper for water splitting. Among the dopants, Si and Ge dopants can narrow the band gap of carbon nitrides about 0.5 - 1.0 eV, and also increase their optical absorption in the visible spectrum. This study presents the potential for doping with isoelectronic elements to greatly improve the photocatalytic characteristics of carbon nitride nanostructures.
• We exploit the knowledge of the nonequilibrium potential in a model for the modulated class A laser. We analyse both, the deterministic and the stochastic dynamics of such a system in terms of the Lyapunov potential. Furthermore, we analyse the stochastic response of such a system and explain it again using the potential in a wide range of parameters and for small values of the noise. Such a response is quantified by means of the amplification factor, founding stochastic resonance within specific parameter's ranges.
• Interaction patterns among individuals play vital roles in spreading infectious diseases. Understanding these patterns and integrating their impacts in modeling diffusion dynamics of infectious diseases are important for epidemiological studies. Current network-based diffusion models assume that diseases transmit through the interactions where both infected and susceptible individuals are co-located at the same time. However, there are several infectious diseases that can transmit when a susceptible individual visits a location after an infected individual has left. Recently, a diffusion model called same place different time (SPDT) transmission was introduced to capture the indirect transmissions that happen when an infected individual leave before a susceptible individual's arrival. In this paper, we demonstrate how these indirect transmission paths significantly enhance the emergence of infectious diseases which are not accounted in the current approach of disease modeling. We denote individuals having indirect links but no direct links during their infectious periods as hidden spreaders. Our simulation shows that outbreak can happen from a single seed node that is a hidden spreader, and the SPDT model captures these effects much better than current models based on the direct links only. The simulation is run on a synthetic SPDT network of 0.3M nodes that are characterized by the movement behaviors of users of a location based online social networking application MOMO.
• We study the long-wavelength excitations of the inner crust of neutron stars, considering three phases: cubic crystal at low densities, rods and plates near the core-crust transition. To describe the phonons, we write an effective Lagrangian density in terms of the coarse-grained phase of the neutron superfluid gap and of the average displacement field of the clusters. The kinetic energy, including the entrainment of the neutron gas by the clusters, is obtained within a superfluid hydrodynamics approach. The potential energy is determined from a model where clusters and neutron gas are considered in phase coexistence, augmented by the elasticity of the lattice due to Coulomb and surface effects. All three phases show strong anisotropy, i.e., angle dependence of the phonon velocities. Consequences for the specific heat at low temperature are discussed.
• Recent progress has been made with Adaptive Multiple Importance Sampling (AMIS) methods that show improvement in effective sample size. However, consistency for the AMIS estimator has only been established in very restricted cases. Furthermore, the high computational complexity of the re-weighting in AMIS (called balance heuristic) makes it expensive for applications involving diffusion processes. In this work we consider sequential and adaptive importance sampling that is particularly suitable for diffusion processes. We propose a new discarding-re-weighting scheme that is of lower computational complexity, and we prove that the resulting AMIS is consistent. Using numerical experiments, we demonstrate that discarding-re-weighting performs very similar to the balance heuristic, but at a fraction of the computational cost.
• The recent detection of gravitational waves and electromagnetic counterparts emitted during and after the collision of two neutron stars marks a breakthrough in the field of multi-messenger astronomy. Numerical relativity simulations are the only tool to describe the binary's merger dynamics in the regime when speeds are largest and gravity is strongest. In this work we report state-of-the-art binary neutron star simulations for irrotational (non-spinning) and spinning configurations. The main use of these simulations is to model the gravitational-wave signal. Key numerical requirements are the understanding of the convergence properties of the numerical data and a detailed error budget. The simulations have been performed on different HPC clusters, they use multiple grid resolutions, and are based on eccentricity reduced quasi-circular initial data. We obtain convergent waveforms with phase errors of 0.5-1.5 rad accumulated over approximately 12 orbits to merger. The waveforms have been used for the construction of a phenomenological waveform model which has been applied for the analysis of the recent binary neutron star detection. Additionally, we show that the data can also be used to test other state-of-the-art semi-analytical waveform models.
• A Gallai coloring is a coloring of the edges of a complete graph without rainbow triangles, and a Gallai $k$-coloring is a Gallai coloring that uses $k$ colors. Given an integer $k\ge1$ and graphs $H_1, H_2, \ldots, H_k$, the Gallai-Ramsey number $GR(H_1, H_2, \ldots, H_k)$ is the least integer $n$ such that every Gallai $k$-coloring of the complete graph $K_n$ contains a monochromatic copy of $H_i$ in color $i$ for some $i \in \{1,2, \ldots, k\}$. When $H = H_1 = \cdots = H_k$, we simply write $GR_k(H)$. We study Gallai-Ramsey numbers of even cycles and paths. For all $n\ge3$ and $k\ge1$, let $G_i=P_{2i+3}$ be a path on $2i+3$ vertices for all $i\in\{0,1, \ldots, n-2\}$ and $G_{n-1}\in\{C_{2n}, P_{2n+1}\}$. Let $i_j\in\{0,1,\ldots, n-1 \}$ for all $j\in\{1,2, \ldots, k\}$ with $i_1\ge i_2\ge\cdots\ge i_k$. The first author recently conjectured that $GR(G_{i_1}, G_{i_2}, \ldots, G_{i_k}) = 3+\min\{i_1,n^*-2\}+\sum_{j=1}^k i_j$, where $n^* =n$ when $G_{i_1}\ne P_{2n+1}$ and $n^* =n+1$ when $G_{i_1}= P_{2n+1}$. The truth of this conjecture implies that $GR_k(C_{2n})=GR_k(P_{2n})=(n-1)k+n+1$ for all $n\ge3$ and $k\ge1$, and $GR_k(P_{2n+1})=(n-1)k+n+2$ for all $n\ge1$ and $k\ge1$. In this paper, we prove that the aforementioned conjecture holds for $n\in\{3,4\}$ and all $k\ge1$. Our proof relies only on Gallai's result and the classical Ramsey numbers $R(H_1, H_2)$, where $H_1, H_2\in\{C_8, C_6, P_7, P_5, P_3\}$. We believe the recoloring method we developed here will be very useful for solving subsequent cases, and perhaps the conjecture.
• The Kuramoto--Sakaguchi model is a modification of the well-known Kuramoto model that adds a phase-lag paramater, or "frustration" to a network of phase-coupled oscillators. The Kuramoto model is a flow of gradient type, but adding a phase-lag breaks the gradient structure, significantly complicating the analysis of the model. We present several results determining the stability of phase-locked configurations: the first of these gives a sufficient condition for stability, and the second a sufficient condition for instability. (In fact, the instability criterion gives a count, modulo 2, of the dimension of the unstable manifold to a fixed point and having an odd count is a sufficient condition for instability of the fixed point.) We also present numerical results for both small and large collections of Kuramoto--Sakaguchi oscillators.
• We propose a numerical method of estimating various physical quantities in lattice (supersymmetric) quantum mechanics. The method consists only of deterministic processes such as computing a product of transfer matrix, and has no statistical uncertainties. We use the numerical quadrature to define the transfer matrix as a finite dimensional matrix, and find that it effectively works by rescaling variable for sufficiently small lattice spacings. For a lattice supersymmetric quantum mechanics, the correlators can be estimated without statistical errors, and the effective masses coincide with the exact solution within very small errors less than 0.001%. The SUSY Ward identity is also precisely studied in compared with the Monte-Carlo method. Our method is not limited to a lattice SUSY quantum mechanics, but is also applicable to any other lattice models of quantum mechanics.
• Heterogeneous networks are networks consisting of different types of nodes and multiple types of edges linking such nodes. While community detection has been extensively developed as a useful technique for analyzing networks that contain only one type of nodes, very few community detection techniques have been developed for heterogeneous networks. In this paper, we propose a modularity based community detection framework for heterogeneous networks. Unlike existing methods, the proposed approach has the flexibility to treat the number of communities as an unknown quantity. We describe a Louvain type maximization method for finding the community structure that maximizes the modularity function. Our simulation results show the advantages of the proposed method over existing methods. Moreover, the proposed modularity function is shown to be consistent under a heterogeneous stochastic blockmodel framework. Analyses of the DBLP four-area dataset and a MovieLens dataset demonstrate the usefulness of the proposed method.
• We study transportation networks controlled by dynamical feedback tolls. We consider a multiscale model in which the dynamics of the traffic flows are intertwined with those of the drivers' route choices. The latter are influenced by the congestion status of the whole network as well as decentralized congestion-dependent tolls. Our main result shows that positive increasing decentralized congestion-dependent tolls allow the system planner to globally stabilise the transportation network around the Wardrop equilibrium. Moreover, using the decentralized marginal costs tolls the stability of the transportation network is around the social optimum traffic assignment.This particularly remarkable as such feedback tolls do not require any global information about the network structure or state and can be computed in a fully local way. We also extend this stability analysis to a constant decentralised feedback tolls and compare their performance both asymptotic and during the transient through numerical simulations.
• We present a model of proton tunnelling across DNA hydrogen bonds, compute the characteristic tunnelling time (CTT) from donor to acceptor and discuss its biological implications. The model is a double oscillator characterised by three geometry parameters describing planar deformations of the H bond, and a symmetry parameter representing the energy ratio between ground states in the individual oscillators. If the symmetry parameter takes its maximum value of 1, then we recover a known model which produced CTTs too large to be biologically relevant; but this is reduced by up to 40 orders of magnitude as the symmetry parameter is decreased. We discover that unless the symmetry parameter is close to 1 or 0, the proton's CTT under any planar deformation is guaranteed to be below one picosecond, which is a biologically relevant time-scale. This supports theories of links between proton tunnelling and biological processes such as spontaneous mutation.
• We report on time series photometry of the faint Neptune irregular satellite Neso. Observations in the V, R, and I pass-bands were performed in photometric conditions at the Cerro Paranal observatory using the instrument FORS2, in the night of July 15th, 2010. Astrometry and photometry derived from these observations are presented here. The time coverage of about six hours does not allow to construct a light curve and derive a meaningful rotational period. However, we could derive new estimates of apparent magnitudes obtaining R=25.2 pm 0.2 mag in agreement with Brozovic, Jacobson, Sheppard (2011), and also V=25.6 pm 0.3 mag, and I=24.5 pm 0.3. In this way we could derive for the first time Neso colors, V-I=1.0 pm 0.4 mag, R-I=0.7 pm 0.4 mag and V-R=0.3 pm 0.4 mag. We compared those colors with those in Peixinho, Delsanti, Doressoundiram (2015). The color R-I appears to be slightly redder than the typical values for Centaurs and KBOs, the color V-I is in nice agreement with both populations. The large error-bars prevents from assigning Neso to any of the reference classes, just looking at Neso colors, although the data seem to suggest that we can rule out its membership in classes of resonant objects or Plutinos.
• In The factorization of the Giry monad (arXiv:1707.00488v2) the author considers two $\sigma$-algebras on convex spaces of functions to the unit interval. One of them is generated by the Boolean subobjects and the other is the $\sigma$-algebra induced by the evaluation maps. The author asserts that, under the assumptions given in the paper, the two $\sigma$-algebras coincide. We give examples contradicting this statement.
• In this article, left g, h-derivation and Jordan left g, h-derivation on algebras are introduced. It is shown that there is no Jordan left g, h-derivation over $\mathcal{M}_n(C)$ and $\mathbb{H}_{\mathbb{R}}$, for g not equal to h. Examples are given which show that every Jordan left $\{g, h\}$-derivation over $\mathcal{T}_n(C)$, $\mathcal{M}_n(C)$ and $\mathbb{H}_{\mathbb{R}}$ are not left $\{g, h\}$-derivations. Moreover, we characterize left $\{g, h\}$-derivation and Jordan left $\{g, h\}$-derivation over $\mathcal{T}_n(C)$, $\mathcal{M}_n(C)$ and $\mathbb{H}_{\mathbb{R}}$ respectively. Also, we prove the result of Jordan left $\{g, h\}$-derivation to be a left $\{g, h\}$-derivation over tensor products of algebras as well as for algebra of polynomials.
• In the regression discontinuity design (RDD), it is common practice to assess the credibility of the design by testing the continuity of the density of the running variable at the cut-off, e.g., McCrary (2008). In this paper we propose a new test for continuity of a density at a point based on the so-called g-order statistics, and study its properties under a novel asymptotic framework. The asymptotic framework is intended to approximate a small sample phenomenon: even though the total number n of observations may be large, the number of effective observations local to the cut-off is often small. Thus, while traditional asymptotics in RDD require a growing number of observations local to the cut-off as n grows, our framework allows for the number q of observations local to the cut-off to be fixed as n grows. The new test is easy to implement, asymptotically valid under weaker conditions than those used by competing methods, exhibits finite sample validity under stronger conditions than those needed for its asymptotic validity, and has favorable power properties against certain alternatives. In a simulation study, we find that the new test controls size remarkably well across designs. We finally apply our test to the design in Lee (2008), a well-known application of the RDD to study incumbency advantage.
• Searching for novel spin caloric effects in antiferromagnets we study the properties of thermally activated magnons in the presence of an external spin current and temperature gradient. We predict the spin Peltier effect -- generation of a heat flux by spin accumulation -- in an antiferromagnetic insulator with cubic or uniaxial magnetic symmetry. This effect is related with spin-current induced splitting of the relaxation times of the magnons with opposite spin direction. We show that the Peltier effect can trigger antiferromagnetic domain wall motion with a force whose value grows with the temperature of a sample. At a temperature, larger than the energy of the low-frequency magnons, this force is much larger than the force caused by direct spin transfer between the spin current and the domain wall. We also demonstrate that the external spin current can induce the magnon spin Seebeck effect. The corresponding Seebeck coefficient is controlled by the current density. These spin-current assisted caloric effects open new ways for the manipulation of the magnetic states in antiferromagnets.
• We confirm Demailly's conjecture on the convergence of higher Lelong numbers under the canonical approximation of a plurisubharmonic function in the case when the function is toric and in the Cegrell class. As applications to convex geometry, we give a unified analytic proof of the Alexandrov-Fenchel inequalities for mixed Monge-Ampère masses, mixed covolumes and mixed multiplicities.
• In this paper, we deal with the following nonlinear Schrödinger equation $$-\epsilon^2∆u+V(x)u=f(u),\ u∈H^1(\mathbb R^2),$$ where $f(t)$ has critical growth of Trudinger-Moser type. By using the variational techniques, we construct a positive solution $u_\epsilon$ concentrating around the saddle points of the potential $V(x)$ as $\epsilon\rightarrow 0$. Our results complete the analysis made in \citeMR2900480 and \citeMR3426106, where the Schrödinger equation was studied in $\mathbb R^N$, $N\geq 3$ for sub-critical and critical case respectively in the sense of Sobolev embedding. Moreover, we relax the monotonicity condition on the nonlinear term $f(t)/t$ together with a compactness assumption on the potential $V(x)$, imposed in \citeMR3503193.
• Thermal and transport properties of hot nuclear matter formed in central $^{129}$Xe + $^{119}$Sn collisions at the Fermi energy are investigated using the isospin-dependent quantum molecular dynamical (IQMD) model. Temperature ($T$), average density ($\rho$), chemical potential ($\mu$), mean momentum ($P$), shear viscosity ($\eta$) and entropy density ($s$) are obtained from the phase-space information. The mean free path ($\lambda_{nn}$) and the in-medium nucleon-nucleon cross section ($\sigma_{nn}$) in the highest compressible stage at different incident energies are deduced and compared with the experimental results from Phys. Rev. C $\bf{90}$ (2014) 064602. The result shows that $\lambda_{nn}$ and $\sigma_{nn}$ have the same trend and similar values as the experimental results when the beam energy is greater than 40 MeV/u at maximum compressed state. Furthermore, the derived shear viscosity over entropy density ($\eta/s$) shows a decreasing behaviour to a saturated value around $\frac{3}{4\pi}$ as a function of incident energy.
• Mar 22 2018 hep-ph astro-ph.HE arXiv:1803.07944v1
We describe several components in the diffuse flux of high energy neutrinos reaching the Earth and discuss whether they could explain IceCube's observations. Then we focus on TeV neutrinos from the Sun. We show that this solar neutrino flux is correlated with the cosmic-ray shadow of the Sun measured by HAWC, and we find that it is much larger than the flux of atmospheric neutrinos. Stars like our Sun provide neutrinos with a very steep spectrum and no associated gammas. We argue that this is the type of contribution that could solve the main puzzle presented by the high energy IceCube data.
• We introduce three alternative angular variables-denoted by $\tilde{\omega}_\text{min}$, $\hat{\omega}_\text{min}$, and $\chi_\text{min}$-for QCD multijet event suppression in supersymmetry searches in events with large missing transverse momentum in proton-proton collisions at the LHC at CERN. In searches in all-hadronic final states in the CMS and ATLAS experiments, the angle $\Delta\varphi_i$, the azimuthal angle between a jet and the missing transverse momentum, is widely used to reduce QCD multijet background events with large missing transverse momentum, which is primarily caused by a jet momentum mismeasurement or neutrinos in hadron decays-the missing transverse momentum is aligned with a jet. A related angular variable-denoted by $\Delta\varphi^*_\text{min}$, the minimum of the azimuthal angles between a jet and the transverse momentum imbalance of the other jets in the event-is used instead in a series of searches in all-hadronic final states in CMS to suppress QCD multijet background events to a negligible level. In this paper, before introducing the alternative variables, we review the variable $\Delta\varphi^*_\text{min}$ in detail and identify room for improvement, in particular, to maintain good acceptances for signal models with high jet multiplicity final states. Furthermore, we demonstrate with simulated event samples that $\hat{\omega}_\text{min}$ and $\chi_\text{min}$ considerably outperform $\Delta\varphi^*_\text{min}$ and $\Delta\varphi_i$ in rejecting QCD multijet background events and that $\hat{\omega}_\text{min}$ and $\tilde{\omega}_\text{min}$ are also useful for reducing the total standard model background events.
• In this article, we show that every Jordan g, h-derivation over T_n(C) is a g, h-derivation under an assumption, where C is a commutative ring with unity 1 not equal to 0. We give an example of a Jordan g, h-derivation over T_n(C) which is not a g, h-derivation. Also, we study Jordan g, h-derivation over M_n(C).
• This paper addresses the problem of cooperative transportation of an object rigidly grasped by N robotic agents. We propose a Nonlinear Model Predictive Control (NMPC) scheme that guarantees the navigation of the object to a desired pose in a bounded workspace with obstacles, while complying with certain input saturations of the agents. The control scheme is based on inter-agent communication and is decentralized in the sense that each agent calculates its own control signal. Moreover, the proposed methodology ensures that the agents do not collide with each other or with the workspace obstacles as well as that they do not pass through singular configurations. The feasibility and convergence analysis of the NMPC are explicitly provided. Finally, simulation results illustrate the validity and efficiency of the proposed method.
• Let C be a commutative ring with unity. In this article, we show that every Jordan derivation over an upper triangular matrix algebra T_n(C) is an inner derivation. Further, we extend the result for Jordan derivation on full matrix algebra M_n(C).
• In this work we propose a family of trajectory tracking controllers for marine craft in the port-Hamiltonian (pH) framework using virtual differential passivity based control (v-dPBC). Two pH models of marine craft are considered, one in a body frame and another in an inertial frame. The structure and workless forces of pH models are exploited to design two virtual control systems which are related to the original marine craft's pH models. These virtual systems are rendered differentially passive with an imposed steady-state trajectory, both by means of a control scheme. Finally, the original marine craft pH models in closed-loop with above controllers solve the trajectory tracking problem. The performance of the closedloop system is evaluated on numerical simulations.
• We present results from 2MASS JKs photometry on the physical reality of recently reported globular cluster (GC) candidates in the Milky Way (MW) bulge. We relied our analysis on photometric membership probabilities that allowed us to distinguish real stellar aggregates from the composite field star population. When building colour-magnitude diagrams and stellar density maps for stars at different membership probability levels, the genuine GC candidate populations are clearly highlighted. We then used the tip of the red giant branch (RGB) as distance estimator, resulting heliocentric distances that place many of the objects in regions near of the MW bulge where no GC had been previously recognised. Some few GC candidates resulted to be MW halo/disc objects.Metallicities estimated from the standard RGB method are in agreement with the values expected according to the position of the GC candidates in the Galaxy. We finally derived from the first time their structural parameters. We found that the studied objects have core, half-light and tidal radii in the ranges spanned by the population of known MW GCs. Their internal dynamical evolutionary stages will be described properly when their masses are estimated.
• We present measurements of the scintillation pulse shape in liquid xenon for nuclear recoils (NR) and electronic recoils (ER) at electric fields of 0 to 0.5 kV/cm for energies $<$ 15 keV and $<$ 70 keV electron-equivalent, respectively. The average pulse shapes are well-described by an effective model with two exponential decay components, where both decay times are fit parameters. We find significant broadening of the pulse for ER due to delayed luminescence from the recombination process. In addition to the effective model, we fit a model describing the recombination luminescence for ER at zero field and obtain good agreement. We estimate the best performance of a combined S2/S1 and pulse shape ER/NR discrimination and show that even with 2 ns time resolution, the improvement over S2/S1 discrimination alone is marginal, so that pulse shape discrimination will likely not be useful for future dual-phase liquid xenon experiments looking for elastic dark matter recoil interactions.
• We investigate the morphology and temporal variability of a quiet Sun network region in different solar layers. The emission in several EUV spectral lines through both raster and slot time series, recorded by EIS/Hinode is studied along with H$\alpha$ observations and high resolution spectropolarimetric observations of the photospheric magnetic field. The photospheric magnetic field is extrapolated up to the corona showing a multitude of large and small scale structures. We show for the first time that the smallest magnetic structures both at the network and the internetwork contribute significantly to the emission in EUV lines, with temperatures ranging from 8 10$^{4}$ K to 6 10$^{5}$ K. Two components of transition region emission are present, one associated with small-scale loops that do not reach coronal temperatures and another one acting as an interface between coronal and chromospheric plasma. Both components are associated with persistent chromospheric structures. The temporal variability of the EUV intensity at the network region is also associated with chromospheric motions, pointing to a connection between transition region and chromospheric features. Intensity enhancements in the EUV transition region lines are preferentially produced by H$\alpha$ upflows. Examination of two individual chromospheric jets shows that their evolution is associated with intensity variations in transition region and coronal temperatures.
• The relation between the mixing matrices of leptons and quarks: $U_{\rm{PMNS}} \approx V_{\rm{CKM}}^\dagger U_0$, where $U_0$ is a matrix of special forms (e.g. BM, TBM), can be a clue for understanding the lepton mixing and neutrino masses. It may imply the Grand unification and existence of a hidden sector with certain symmetry which generates $U_0$ and leads to the smallness of neutrino masses. We apply the residual symmetry approach to obtain $U_0$. The residual symmetries of both the visible and hidden sectors are $\mathbb{Z}_{2} \times \mathbb{Z}_{2}$. Their embedding in a unified flavor group is considered. We find that there are only several possible structures of $U_0$, including the BM mixing and matrices with elements determined by the golden ratio. Realization of the BM scenario based on the $SO(10)$ GUT with the $S_4$ flavor group is presented. Generic features of this scenario are discussed, in particular, the prediction of CP phase $144^{\circ}\lesssim\delta_{\rm CP}\lesssim 210^{\circ}$ in the minimal version.
• We give simple homological conditions for a rational homology 3-sphere Y to have infinite order in the rational homology cobordism group, and for a collection of rational homology spheres to be linearly independent. These translate immediately to statements about knot concordance when Y is the branched double cover of a knot, recovering some results of Livingston and Naik. The statements depend only on the homology groups of the 3-manifolds, but are proven through an analysis of correction terms and their behavior under connected sums.
• This chapter describes the synthesis and some characteristics of magnetic iron oxide nanoparticles, mainly nanocubes, and focus on their self-assembly into crystalline cuboids in dispersion. The influence of external magnetic fields, the concentration of particles, and the temperature on the assembly process is experimentally investigated.
• We show that by adding only two fitting parameters to a purely ballistic transport model, we can accurately characterize the current-voltage characteristics of nanoscale MOSFETs. The model is an extension to a ballistic model (J. Appl. Phys. 76, 4879 (1994)) and includes transmission probability and the drain-channel coupling capacitor. The latter parameter gives rise to a theoretical RON that is significantly larger than those predicted previously. To validate our model, we fabricated n-channel MOSFETs with varying channel lengths. We show the length dependence of these parameters to support a quasi-ballistic description of our devices.
• We explore the cosmic censorship in the Einstein-Maxwell-dilaton theory following Wald's thought experiment to destroy a black hole by throwing in a test particle. We discover that at probe limit the extremal charged dilaton black hole could be destroyed by a test particle with specific energy. Nevertheless the censorship is well protected if backreaction or self-force is included. At the end, we discuss an interesting connection between Hoop Conjecture and Weak Gravity Conjecture.
• We fabricated a non-local spin valve device with Co-MgO injector/detector tunnel contacts on a graphene spin channel. In this device, the spin polarization of the injector contact can be tuned by both the injector current bias and the gate voltage. The spin polarization can be turned off and even inverted. This behavior enables a novel type of spin transistor where the signal is switched off by turning off the spin injection using the field-effect.
• We introduce a model for the short-term dynamics of financial assets based on an application to finance of quantum gauge theory, developing ideas of Ilinski. We present a numerical algorithm for the computation of the probability distribution of prices and compare the results with APPLE stocks prices and the S&P500 index.
• We calculate the three- and four-particle correlations of identical pions in an evolving pion gas (EPG) model with Bose-Einstein condensation. The multi-pion correlation functions in the EPG model are analyzed in different momentum intervals and compared with the experimental data for Pb-Pb collisions at $\sqrt{s_{NN}}=2.76$ TeV. It is found that the multi-pion correlation functions and cumulant correlation functions are sensitive to the condensation fraction of the EPG sources in the low average transverse-momentum intervals of the three and four pions. The model results of the multi-pion correlations are consistent with the experimental data in a considerable degree, which gives a source condensation fraction between 16~--~47\%.

Luis Cruz Mar 16 2018 15:34 UTC

Related Work:

- [Performance-Based Guidelines for Energy Efficient Mobile Applications](http://ieeexplore.ieee.org/document/7972717/)
- [Leafactor: Improving Energy Efficiency of Android Apps via Automatic Refactoring](http://ieeexplore.ieee.org/document/7972807/)

Dan Elton Mar 16 2018 04:36 UTC

Code is open source and available at :
[https://github.com/delton137/PIMD-F90][1]

[1]: https://github.com/delton137/PIMD-F90

Danial Dervovic Mar 01 2018 12:08 UTC

Hello again Māris, many thanks for your patience. Your comments and questions have given me much food for thought, and scope for an amended version of the paper -- please see my responses below.

Please if any of the authors of [AST17 [arXiv:1712.01609](https://arxiv.org/abs/1712.01609)] have any fu

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igorot Feb 28 2018 05:19 UTC

The Igorots built an [online community][1] that helps in the exchange, revitalization, practice, and learning of indigenous culture. It is the first and only Igorot community on the web.

[1]: https://www.igorotage.com/

Beni Yoshida Feb 13 2018 19:53 UTC

This is not a direct answer to your question, but may give some intuition to formulate the problem in a more precise language. (And I simplify the discussion drastically). Consider a static slice of an empty AdS space (just a hyperbolic space) and imagine an operator which creates a particle at some

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Abhinav Deshpande Feb 10 2018 15:42 UTC

I see. Yes, the epsilon ball issue seems to be a thorny one in the prevalent definition, since the gate complexity to reach a target state from any of a fixed set of initial states depends on epsilon, and not in a very nice way (I imagine that it's all riddled with discontinuities). It would be inte

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Elizabeth Crosson Feb 10 2018 05:49 UTC

Thanks for the correction Abhinav, indeed I meant that the complexity of |psi(t)> grows linearly with t.

Producing an arbitrary state |phi> exactly is also too demanding for the circuit model, by the well-known argument that given any finite set of gates, the set of states that can be reached i

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Abhinav Deshpande Feb 09 2018 20:21 UTC

Elizabeth, interesting comment! Did you mean to say that the complexity of $U(t)$ increases linearly with $t$ as opposed to exponentially?

Also, I'm confused about your definition. First, let us assume that the initial state is well defined and is $|\psi(0)\rangle$.
If you define the complexit

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Elizabeth Crosson Feb 08 2018 04:27 UTC

The complexity of a state depends on the dynamics that one is allowed to use to generate the state. If we restrict the dynamics to be "evolving according a specific Hamiltonian H" then we immediately have that the complexity of U(t) = exp(i H t) grows exponentially with t, up until recurrences that

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Danial Dervovic Feb 05 2018 15:03 UTC

Thank you Māris for the extremely well thought-out and articulated points here.

I think this very clearly highlights the need to think explicitly about the precompute time if using the lifting to directly simulate the quantum walk, amongst other things.

I wish to give a well-considered respons

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