November 2018 arXiv papers — page 7
Showing 601–700 of 13,020 papers
E. Aprile, J. Aalbers, F. Agostini, M. Alfonsi
We present first results on the scalar WIMP-pion coupling from 1 t$\times$yr of exposure with the XENON1T experiment. This interaction is generated when the WIMP couples to a virtual pion exchanged between the nucleons in a nucleus. In contrast to most non-relativistic operators, these pion-exchange currents can be coherently enhanced by the total number of
Zhuo Hui, Ayan Chakrabarti, Kalyan Sunkavalli, Aswin C. Sankaranarayanan
We present a method to separate a single image captured under two illuminants, with different spectra, into the two images corresponding to the appearance of the scene under each individual illuminant. We do this by training a deep neural network to predict the per-pixel reflectance chromaticity of the scene, which we use in conjunction with a previous flash
Peijun Li, Lei Zhang
Consider the scattering of an acoustic plane wave by a bounded elastic obstacle which is immersed in an open space filled with a homogeneous medium. This paper concerns the mathematical analysis of the coupled two- and three-dimensional acoustic-elastic wave propagation problem in the time-domain. A compressed coordinate transformation is proposed to reduce
S. J. Brooks
Particle colliders have been remarkably successful tools in particle and nuclear physics. What are the future trends and limitations of accelerators as they currently exist, and are there possible alternative approaches? What would the ultimate collider look like? This talk examines some challenges and possible solutions. Accelerating a single particle rathe
Jianliang Li, Tapio Helin, Peijun Li
This paper concerns the random source problems for the time-harmonic acoustic and elastic wave equations in two and three dimensions. The goal is to determine the compactly supported external force from the radiated wave field measured in a domain away from the source region. The source is assumed to be a microlocally isotropic generalized Gaussian random fu
Influence of Young's modulus temperature dependence on parametric instability in Advanced LIGO interferometer
astro-ph.IMS. E. Strigin
We discuss the influence of Young's modulus temperature dependence on the number of parametrically unstable modes in a Fabry-Perot cavity of Advanced LIGO interferometer. Some unstable modes may be suppressed by changing the mirror's temperature due to temperature dependence of Young's modulus. Varying the temperature of the mirrors we can change their frequ
Security, Privacy and Safety Risk Assessment for Virtual Reality Learning Environment Applications
cs.HCAniket Gulhane, Akhil Vyas, Reshmi Mitra, Roland Oruche
Social Virtual Reality based Learning Environments (VRLEs) such as vSocial render instructional content in a three-dimensional immersive computer experience for training youth with learning impediments. There are limited prior works that explored attack vulnerability in VR technology, and hence there is a need for systematic frameworks to quantify risks corr
Kostiantyn Ralchenko, Georgiy Shevchenko
For a class of non-autonomous parabolic stochastic partial differential equations defined on a bounded open subset $D\subset \mathbb {R}^d$ and driven by an $L^2(D)$-valued fractional Brownian motion with the Hurst index $H>1/2$, a new result on existence and uniqueness of a mild solution is established. Compared to the existing results, the uniqueness in a
Georgios Minadakis, Katrin Lohan
In this paper, we will present a method for measuring cognitive load and online real-time feedback using the Tobii Pro 2 eye-tracking glasses. The system is envisaged to be capable of estimating high cognitive load states and situations, and adjust human-machine interfaces to the user's needs. The system is using well-known metrics such as average pupillary
Josep M. Masqué, Solay Jeyakumar, Miguel A. Trinidad, Tatiana Rodríguez-Esnard
We report continuum GMRT observations aimed to explore the behavior of the jet associated with IRAS 16547-4247 at very low frequencies (325 MHz and 610 MHz). The obtained maps reveal an elongated morphology in the SE-NW direction. In addition, the 610 MHz map shows three knots associated to the elongated morphology that seems to correspond to the triple radi
Sylvain Crovisier, Dawei Yang, Jinhua Zhang
In this paper, we study the limit measures of the empirical measures of Lebesgue almost every point in the basin of a partially hyperbolic attractor. They are strongly related to a notion named Gibbs u-state, which can be defined in a large class of diffeomorphisms with less regularity and which is the same as Pesin-Sinai's notion for partially hyperbolic at
Dömötör Pálvölgyi, Gábor Tardos
In this note we disprove a conjecture of Kuzmin and Warmuth claiming that every family whose VC-dimension is at most d admits an unlabeled compression scheme to a sample of size at most d. We also study the unlabeled compression schemes of the joins of some families and conjecture that these give a larger gap between the VC-dimension and the size of the smal
Arjun Nitin Bhagoji, Supriyo Chakraborty, Prateek Mittal, Seraphin Calo
Federated learning distributes model training among a multitude of agents, who, guided by privacy concerns, perform training using their local data but share only model parameter updates, for iterative aggregation at the server. In this work, we explore the threat of model poisoning attacks on federated learning initiated by a single, non-colluding malicious
Úlfar Erlingsson, Vitaly Feldman, Ilya Mironov, Ananth Raghunathan
Sensitive statistics are often collected across sets of users, with repeated collection of reports done over time. For example, trends in users' private preferences or software usage may be monitored via such reports. We study the collection of such statistics in the local differential privacy (LDP) model, and describe an algorithm whose privacy cost is poly
Luis Fredes, Amitai Linker, Daniel Remenik
We investigate the effect on survival and coexistence of introducing forest fire epidemics to a certain two-species competition model. The model is an extension of the one introduced by Durrett and Remenik [DR09], who studied a discrete time particle system running on a random 3-regular graph where occupied sites grow until they become sufficiently dense so
Moeness G. Amin, Zhengxin Zeng, Tao Shan
We introduce a simple but effective technique in automatic hand gesture recognition using radar. The proposed technique classifies hand gestures based on the envelopes of their micro-Doppler signatures. These envelopes capture the distinctions among different hand movements and their corresponding positive and negative Doppler frequencies which are generated
Henry Bendekgey
We consider the performance of the foremost academic House of Representatives forecasting models in the 2018 elections. In creating open-source implementations of these models, we outline key underlying assumptions. We find that although the results were unsurprising, they indicate a weakening of many traditional forecasting indicators.
Danil Kuzin, Olga Isupova, Lyudmila Mihaylova
A novel method to propagate uncertainty through the soft-thresholding nonlinearity is proposed in this paper. At every layer the current distribution of the target vector is represented as a spike and slab distribution, which represents the probabilities of each variable being zero, or Gaussian-distributed. Using the proposed method of uncertainty propagatio
Increasing the Capability of Neural Networks for Surface Reconstruction from Noisy Point Clouds
cs.GRAdam R White, Li Bai
This paper builds upon the current methods to increase their capability and automation for 3D surface construction from noisy and potentially sparse point clouds. It presents an analysis of an artificial neural network surface regression and mapping method, describing caveats, improvements and justification for the different approach.
Aditya Gangrade, Praveen Venkatesh, Bobak Nazer, Venkatesh Saligrama
We propose and analyze the problems of \textit{community goodness-of-fit and two-sample testing} for stochastic block models (SBM), where changes arise due to modification in community memberships of nodes. Motivated by practical applications, we consider the challenging sparse regime, where expected node degrees are constant, and the inter-community mean de
G. B. Mainland, Bernard Mulligan
Particle-antiparticle pairs are predicted by quantum field theory to appear as vacuum fluctuations. The model of the vacuum used here is postulated to have the following properties: To minimize the violation of conservation energy allowed by the Heisenberg uncertainty principle and to avoid violating conservation of angular momentum, vacuum fluctuations of c
Daniel Ritchie, Kai Wang, Yu-an Lin
We present a new, fast and flexible pipeline for indoor scene synthesis that is based on deep convolutional generative models. Our method operates on a top-down image-based representation, and inserts objects iteratively into the scene by predicting their category, location, orientation and size with separate neural network modules. Our pipeline naturally su
Philip F. Hopkins, Michael Y. Grudic, Andrew R. Wetzel, Dusan Keres
Radiative feedback (RFB) from stars plays a key role in galaxies, but remains poorly-understood. We explore this using high-resolution, multi-frequency radiation-hydrodynamics (RHD) simulations from the Feedback In Realistic Environments (FIRE) project. We study ultra-faint dwarf through Milky Way mass scales, including H+He photo-ionization; photo-electric,
David Gontier, Christian Hainzl, Mathieu Lewin
The Hartree-Fock ground state of the Homogeneous Electron Gas is never translation invariant, even at high densities. As proved by Overhauser, the (paramagnetic) free Fermi Gas is always unstable under the formation of spin or charge density waves. We give here the first explicit bound on the energy gain due to the breaking of translational symmetry. Our bou
Miguel A. Alejo, José Luis López
In this paper, global well-posedness of the non-Markovian Unruh-Zurek and Hu-Paz-Zhang master equations with nonlinear electrostatic coupling is demonstrated. They both consist of a Wigner-Poisson like equation subjected to a dissipative Fokker-Planck mechanism with time-dependent coefficients of integral type, which makes necessary to take into account the
Christos-Alexandros Psomas, Ariel Schvartzman, S. Matthew Weinberg
Consider a seller with m heterogeneous items for sale to a single additive buyer whose values for the items are arbitrarily correlated. It was previously shown that, in such settings, distributions exist for which the seller's optimal revenue is infinite, but the best "simple" mechanism achieves revenue at most one ([Briest et. al 15], [Hart and Nisan 13]),
Daniele Oriti
This is a brief, popular (non-technical) introduction (in Italian language) to the problem of quantum gravity, to the recent perspective of emergent spacetime and to its (potential) realization in the context of group field theories, in which the universe emerges as a condensate of non-spatiotemporal constituents.
M. J. Rain, S. Villanova, C. Muñoz, C. Valenzuela-Calderon
We present the abundances analysis for a sample of 11 red giant branch stars in the metal-poor globular cluster NGC 6809 based on high-resolution spectra. Our main goals are to characterize its chemical composition and analyze this cluster's behavior associated with the Multiple Population (MPs) phenomenon. In our work we obtained the stellar parameters and
Savvas Varsamopoulos, Koen Bertels, Carmen G. Almudever
Matching algorithms can be used for identifying errors in quantum systems, being the most famous the Blossom algorithm. Recent works have shown that small distance quantum error correction codes can be efficiently decoded by employing machine learning techniques based on neural networks (NN). Various NN-based decoders have been proposed to enhance the decodi
Unifying Decision-Making: a Review on Evolutionary Theories on Rationality and Cognitive Biases
cs.AICatarina Moreira
In this paper, we make a review on the concepts of rationality across several different fields, namely in economics, psychology and evolutionary biology and behavioural ecology. We review how processes like natural selection can help us understand the evolution of cognition and how cognitive biases might be a consequence of this natural selection. In the end
A rule-based system proposal to aid in the evaluation and decision-making in external beam radiation treatment planning
cs.SER. C. Fernandes, T. M. Machado, H. J. Onisto, A. D. Muñoz
As part of a plan launched by the Ministry of Health of Brazil to increase the availability of linear accelerators for radiotherapy treatment for the whole country, for which Varian Medical Systems company has won the bidding, a technical cooperation agreement was signed inviting Brazilian Scientific and Technological Institutions to participate in a technol
Kelly Milliner, James H. Matthews, Knox S. Long, Lee Hartmann
We present disc wind models aimed at reproducing the main features of the strong Na I resonance line P-Cygni profiles in the rapidly-accreting pre-main sequence FU Ori objects. We conducted Monte Carlo radiative transfer simulations for a standard magnetocentrifugally driven wind (MHD) model and our own "Genwind" models, which allows for a more flexible wind
Rafia Malik, Mai Vu
This paper investigates wireless information and power transfer in a full-duplex MIMO relay channel where the self-sustained relay harvests energy from both source transmit signal and self-interference signal to decode and forward source information to a destination. We present a novel technique to jointly optimize power splitting at the relay and precoding
Unveiling the nature of candidate high-mass young stellar objects in the Magellanic Clouds with near-IR spectroscopy
astro-ph.GAMegan Reiter, Omnarayani Nayak, Margaret Meixner, Olivia Jones
As nearby neighbors to the Milky Way, the Large and Small Magellanic Clouds (LMC and SMC) provide a unique opportunity to study star formation in the context of their galactic ecosystems. Thousands of young stellar objects (YSOs) have been characterized with large-scale Spitzer and Herschel surveys. In this paper, we present new near-IR spectroscopy of five
Francesco Malandrino, Carla-Fabiana Chiasserini, Claudio Casetti, Luca Chiaraviglio
Climate changes brought about by global warming as well as man-made environmental changes are often the cause of sever natural disasters. ICT, which is itself responsible for global warming due to its high carbon footprint, can play a role in alleviating the consequences of such hazards by providing reliable, resilient means of communication during a disaste
On estimates for fully nonlinear elliptic equations with Neumann boundary conditions on Riemannian Manifolds
math.APBo Guan, Ni Xiang
We derive gradient and second order {\em a priori} estimates for solutions of the Neumann problem for a general class of fully nonlinear elliptic equations on compact Riemannian manifolds with boundary. These estimates yield regularity and existence results.
Ori Sberlo, Amir Shpilka
This work proves new results on the ability of binary Reed-Muller codes to decode from random errors and erasures. We obtain these results by proving improved bounds on the weight distribution of Reed-Muller codes of high degrees. Specifically, given weight $\beta \in (0,1)$ we prove an upper bound on the number of codewords of relative weight at most $\beta
Manuel Drees, Meng Shi, Zhongyi Zhang
In this study, we apply LHC data to constrain the extension of the Standard Model by an anomaly-free $U(1)_{L_\mu-L_\tau}$ gauge group; this model contains a new gauge boson ($Z^\prime$) and a scalar dark matter particle ($\phi_{\rm DM}$). We recast a large number of LHC analyses from ATLAS and CMS of multi-lepton final states. We find that for $10$ GeV $< m
Gaussian asymptotic limits for the $\alpha$-transformation in the analysis of compositional data
math.STYannis Pantazis, Michail Tsagris, Andrew T. A. Wood
Compositional data consists of vectors of proportions whose components sum to 1. Such vectors lie in the standard simplex, which is a manifold with boundary. One issue that has been rather controversial within the field of compositional data analysis is the choice of metric on the simplex. One popular possibility has been to use the metric implied by logtran
Optimal Decision Rules for Simple Hypothesis Testing under General Criterion Involving Error Probabilities
eess.SPBerkan Dulek, Cuneyd Ozturk, Sinan Gezici
The problem of simple $M-$ary hypothesis testing under a generic performance criterion that depends on arbitrary functions of error probabilities is considered. Using results from convex analysis, it is proved that an optimal decision rule can be characterized as a randomization among at most two deterministic decision rules, of the form reminiscent to Bayes
Hsiang Hsu, Flavio P. Calmon, José Cândido Silveira Santos Filho, Andre P. Calmon
We analyze expenditure patterns of discretionary funds by Brazilian congress members. This analysis is based on a large dataset containing over $7$ million expenses made publicly available by the Brazilian government. This dataset has, up to now, remained widely untouched by machine learning methods. Our main contributions are two-fold: (i) we provide a nove
Xian Yeow Lee, Aditya Balu, Daniel Stoecklein, Baskar Ganapathysubramanian
Microfluidic devices are utilized to control and direct flow behavior in a wide variety of applications, particularly in medical diagnostics. A particularly popular form of microfluidics -- called inertial microfluidic flow sculpting -- involves placing a sequence of pillars to controllably deform an initial flow field into a desired one. Inertial flow sculp
Simulated Tempering Langevin Monte Carlo II: An Improved Proof using Soft Markov Chain Decomposition
cs.LGRong Ge, Holden Lee, Andrej Risteski
A key task in Bayesian machine learning is sampling from distributions that are only specified up to a partition function (i.e., constant of proportionality). One prevalent example of this is sampling posteriors in parametric distributions, such as latent-variable generative models. However sampling (even very approximately) can be #P-hard. Classical results
Manuel Gessner, Augusto Smerzi, Luca Pezzè
The well known metrological linear squeezing parameters (such as quadrature or spin squeezing) efficiently quantify the sensitivity of Gaussian states. Yet, these parameters are insufficient to characterize the much wider class of highly sensitive non-Gaussian states. Here, we introduce a class of metrological nonlinear squeezing parameters obtained by analy
Microstructure and formation mechanisms of {\delta}-hydrides in variable grain size Zircaloy-4 studied by electron backscatter diffraction
cond-mat.mtrl-sciSiyang Wang, Finn Giuliani, T. Ben Britton
Microstructure and crystallography of {\delta} phase hydrides in as-received fine grain and 'blocky' alpha large grain Zircaloy-4 (average grain size ~11 {\mu}m and >200 {\mu}m, respectively) were examined using electron backscatter diffraction. Results suggest that the the matrix-hydride orientation relationship is {0001}{\alpha}||{111}{\delta};<11-20>{\alp
Sandeep Silwal
In this short paper we present an elementary proof of the infinitude of primes. Our proof is similar in spirit to Euler's proof that the reciprocals of primes diverges and only uses tools from elementary number theory and calculus. In addition, our proof highlights an interesting use of generating functions.
Tirthankar Banerjee, Niladri Sarkar, John Toner, Abhik Basu
We show that inversion-asymmetric tethered membranes exhibit a new double-spiral phase with long range orientational order not present in symmetric membranes. We calculate the universal algebraic spiral shapes of these membranes in this phase. Asymmetry can trigger the crumpling of these membranes as well. In-vitro experiments on lipid, red blood cell membra
T. Adams, M. Garst, A. Bauer, R. Georgii
We report high-precision small angle neutron scattering of the orientation of the skyrmion lattice in a spherical sample of MnSi under systematic changes of the magnetic field direction. For all field directions the skyrmion lattice may be accurately described as a triple-$\vec{Q}$ state, where the modulus $\vert \vec{Q} \vert$ is constant and the wave vecto
Viljami Leino, Kari Rummukainen, Joni M. Suorsa, Kimmo Tuominen
We review our recent results on the infrared behaviour of the SU(2) gauge theory with $N_f$ massless fundamental flavour fermions. We have analyzed the running of the coupling in SU(2) gauge theories with six and eight fermionic flavours using the gradient flow step scaling method. From the running of the coupling, we see a clear indication of an infrared st
Jack Richings, Carlos Frenk, Adrian Jenkins, Andrew Robertson
N-body simulations make unambiguous predictions for the abundance of substructures within dark matter halos. However, the inclusion of baryons in the simulations changes the picture because processes associated with the presence of a large galaxy in the halo can destroy subhalos and substantially alter the mass function and velocity distribution of subhalos.
Jiaqi Jiang, David Sell, Stephan Hoyer, Jason Hickey
A key challenge in metasurface design is the development of algorithms that can effectively and efficiently produce high performance devices. Design methods based on iterative optimization can push the performance limits of metasurfaces, but they require extensive computational resources that limit their implementation to small numbers of microscale devices.
Ian M. Shoemaker, Jason Wyenberg
Heavy sterile neutrinos are typically invoked to accommodate the observed neutrino masses, by positing a new Yukawa term connecting these new states to the neutrinos in the electroweak doublet. However, given our ignorance of the neutrino sector we should explore additional interactions such sterile neutrinos may have with the SM. In this paper, we study the
The Plane's The Thing: The Case for Wide-Fast-Deep Coverage of the Galactic Plane and Bulge
astro-ph.GAJay Strader, Elias Aydi, Christopher Britt, Adam Burgasser
We argue that the exclusion of the Galactic Plane and Bulge from the uniform wide-fast-deep (WFD) LSST survey cadence is fundamentally inconsistent with two of the main science drivers of LSST: Mapping the Milky Way and Exploring the Transient Optical Sky. We outline the philosophical basis for this claim and then describe a number of important science goals
Zuxuan Wu, Caiming Xiong, Chih-Yao Ma, Richard Socher
We present AdaFrame, a framework that adaptively selects relevant frames on a per-input basis for fast video recognition. AdaFrame contains a Long Short-Term Memory network augmented with a global memory that provides context information for searching which frames to use over time. Trained with policy gradient methods, AdaFrame generates a prediction, determ
A. Arhrib, R. Benbrik, M. EL Kacimi, L. Rahili
We study the phenomenology of the two Higgs doublet model with a real singlet scalar $S$ (2HDMS). The model predicts three CP-even Higgses $h_{1,2,3}$, one CP-odd $A^0$ and a pair of charged Higgs. We discuss the consistency of the 2HDMS with theoretical as well as with all available experimental data. In contrast with previous studies, we focus on the scena
Yuri Kondratiev, Oleksandr Kutoviy, Sergey Pirogov, Elena Zhizhina
We study invariant measures of continuous contact model in small dimensional spaces ($d =1,2$). Under general conditions we prove that in the critical regime this system has the one-parameter set of invariant measures parametrized by the spatial density of particles. Also for broad class of initial states we prove the convergence to one of these invariant me
Kamiokande Collaboration, S. Sussman, K. Abe, C. Bronner
Using 0.37 megaton$\cdot$years of exposure from the Super-Kamiokande detector, we search for 10 dinucleon and nucleon decay modes that have a two-body final state with no hadrons. These baryon and lepton number violating modes have the potential to probe theories of unification and baryogenesis. For five of these modes the searches are novel, and for the oth
Wen Chen, Odysseas Kanavetas, Michael N. Katehakis
In this paper we introduce the Ameso optimization problem, a special class of discrete optimization problems. We establish its basic properties and investigate the relation between Ameso optimization and the convex optimization. Further, we design an algorithm to solve a multi-dimensional Ameso problem by solving a sequence of one-dimensional Ameso problems.
Upper bounds on the superfluid stiffness and superconducting $T_c$: Applications to twisted-bilayer graphene and ultra-cold Fermi gases
cond-mat.supr-conTamaghna Hazra, Nishchhal Verma, Mohit Randeria
Understanding the material parameters that control the superconducting transition temperature $T_c$ is a problem of fundamental importance. In many novel superconductors, phase fluctuations determine $T_c$, rather than the collapse of the pairing amplitude. We derive rigorous upper bounds on the superfluid phase stiffness for multi-band systems, valid in any
Black Hole Accretion Discs and Luminous Transients in Failed Supernovae from Non-Rotating Supergiants
astro-ph.SREliot Quataert, Daniel Lecoanet, Eric R. Coughlin
We show that for supergiants, net angular momentum is not a necessary condition for forming accretion discs during core-collapse. Even absent net rotation, convective motions in the outer parts of supergiants generate mean horizontal flows at a given radius with velocities of order 1 km/s; the direction of the mean flow will vary as a function of height thro
Federica Maria Surace, Angelo Russomanno, Marcello Dalmonte, Alessandro Silva
We construct a class of period-$n$-tupling discrete time crystals based on $\mathbb{Z}_n$ clock variables, for all the integers $n$. We consider two classes of systems where this phenomenology occurs, disordered models with short-range interactions and fully connected models. In the case of short-range models we provide a complete classification of time-crys
Annabelle Bohrdt, Christie S. Chiu, Geoffrey Ji, Muqing Xu
Quantum gas microscopes for ultracold atoms can provide high-resolution real-space snapshots of complex many-body systems. We implement machine learning to analyze and classify such snapshots of ultracold atoms. Specifically, we compare the data from an experimental realization of the two-dimensional Fermi-Hubbard model to two theoretical approaches: a doped
João L. Costa, José Natário
We study the free boundary problem for the "hard phase" material introduced by Christodoulou, both for rods in (1+1)-dimensional Minkowski spacetime and for spherically symmetric balls in (3+1)-dimensional Minkowski spacetime. Unlike Christodoulou, we do not consider a "soft phase", and so we regard this material as an elastic medium, capable of both compres
Variational optimization in the AI era: Computational Graph States and Supervised Wave-function Optimization
cond-mat.str-elDmitrii Kochkov, Bryan K. Clark
Representing a target quantum state by a compact, efficient variational wave-function is an important approach to the quantum many-body problem. In this approach, the main challenges include the design of a suitable variational ansatz and optimization of its parameters. In this work, we address both of these challenges. First, we define the variational class
Pierandrea Guarnieri, Claudia Maraston, Daniel Thomas, Janine Pforr
Using stellar population models, we predicted that the Dark Energy Survey (DES) - due to its special combination of area (5000 deg. sq.) and depth ($i = 24.3$) - would be in the position to detect massive ($\gtrsim 10^{11}$ M$_{\odot}$) galaxies at $z \sim 4$. We confront those theoretical calculations with the first $\sim 150$ deg. sq. of DES data reaching
Jonathan Squire, Alexander A. Schekochihin, Eliot Quataert, Matthew W. Kunz
We propose that pressure anisotropy causes weakly collisional turbulent plasmas to self-organize so as to resist changes in magnetic-field strength. We term this effect "magneto-immutability" by analogy with incompressibility (resistance to changes in pressure). The effect is important when the pressure anisotropy becomes comparable to the magnetic pressure,
Using a Recurrent Neural Network to Reconstruct Quantum Dynamics of a Superconducting Qubit from Physical Observations
quant-phEmmanuel Flurin, Leigh S. Martin, Shay Hacohen-Gourgy, Irfan Siddiqi
At its core, Quantum Mechanics is a theory developed to describe fundamental observations in the spectroscopy of solids and gases. Despite these practical roots, however, quantum theory is infamous for being highly counterintuitive, largely due to its intrinsically probabilistic nature. Neural networks have recently emerged as a powerful tool that can extrac
Chrysoula Markou, Felix J. Rudolph, Angnis Schmidt-May
This work proposes a new gravitational theory formulated in terms of the vierbein field. The vierbein contains components which can be shifted by local Lorentz transformations and therefore do not show up in the spacetime metric. These components are given dynamics and become physical in our setup. They enter the massless theory in the form of an antisymmetr
Dario Tamascelli, Andrea Smirne, James Lim, Susana F. Huelga
Chain-mapping techniques in combination with the time-dependent density matrix renormalization group are a powerful tool for the simulation of open-system quantum dynamics. For finite-temperature environments, however, this approach suffers from an unfavorable algorithmic scaling with increasing temperature. We prove that the system dynamics under thermal en
D. Rosado-Belza, U. Lisenfeld, J. Hibbard, K. Kniermann
UGC 10214 is a minor merger in which a dwarf galaxy has interacted with a large spiral galaxy $\sim$250 Myr ago and produced a perturbed disk and a giant tidal tail. We use a multiwavelength dataset in order to study the present and past star formation rate (SFR) and its relation to the gas and stellar mass at a spatial resolution down to 4 kpc. UGC 10214 is
Laura A. Lopez, Brian W. Grefenstette, Katie Auchettl, Kristin K. Madsen
We present evidence of diffuse, non-thermal X-ray emission from the superbubble 30 Doradus C (30 Dor C) using hard X-ray images and spectra from NuSTAR observations. For this analysis, we utilize data from a 200 ks targeted observation of 30 Dor C as well as 2.8 Ms of serendipitous off-axis observations from the monitoring of nearby SN 1987A. The complete sh
Interacting spin-3/2 fermions in a Luttinger semimetal: Competing phases and their selection in the global phase diagram
cond-mat.str-elAndras Szabo, Roderich Moessner, Bitan Roy
We compute the effects of electronic interactions on gapless spin-3/2 excitations that in a noninteracting system emerge at a bi-quadratic touching of Kramers degenerate valence and conduction bands, known as Luttinger semimetal. This model can describe the low-energy physics of HgTe, gray-Sn, 227 pyrochlore iridates and half-Heuslers. For the sake of concre
Megan Ansdell, Eric Gaidos, Tom L. Jacobs, Andrew W. Mann
We describe EPIC 205718330 and EPIC 235240266, two systems identified in the K2 data whose light curves contain episodic drops in brightness with shapes and durations similar to those of the young "dipper" stars, yet shallower by ~1-2 orders of magnitude. These "little dippers" have diverse profile shapes with durations of ~0.5-1.0 days and depths of ~0.1-1.
Tyler Kelley, James S. Bullock, Shea Garrison-Kimmel, Michael Boylan-Kolchin
We introduce an extension of the ELVIS project to account for the effects of the Milky Way galaxy on its subhalo population. Our simulation suite, Phat ELVIS, consists of twelve high-resolution cosmological dark matter-only (DMO) zoom simulations of Milky Way-size $\Lambda$CDM~ haloes ($M_{\rm v} = 0.7-2 \times 10^{12} \,\mathrm{M}_\odot$) along with twelve
First detection of scale-dependent linear halo bias in $N$-body simulations with massive neutrinos
astro-ph.COChi-Ting Chiang, Marilena LoVerde, Francisco Villaescusa-Navarro
Using $N$-body simulations with massive neutrino density perturbations, we detect the scale-dependent linear halo bias with high significance. This is the first time that this effect is detected in simulations containing neutrino density perturbations on all scales, confirming the same finding from separate universe simulations. The scale dependence is the r
High-resolution Charge Exchange Spectra with L-shell Nickel Show Striking Differences from Models
astro-ph.HEG. L. Betancourt-Martinez, P. Beiersdorfer, G. V. Brown, R. S. Cumbee
We present the first high-resolution laboratory spectra of X-ray emission following L-shell charge exchange between nickel ions and neutral H2 and He. We employ the commonly used charge exchange models found in XSPEC and SPEX, ACX and SPEX-CX, to simulate our experimental results. We show that significant differences between data and models exist in both lin
Cameron B. Hummels, Britton D. Smith, Philip F. Hopkins, Brian W. O'Shea
Traditional cosmological hydrodynamics simulations fail to spatially resolve the circumgalatic medium (CGM), the reservoir of tenuous gas surrounding a galaxy and extending to its virial radius. We introduce the technique of Enhanced Halo Resolution (EHR), enabling more realistic physical modeling of the simulated CGM by consistently forcing gas refinement t
Ke Li, Jitendra Malik
Generative adversarial nets (GANs) have generated a lot of excitement. Despite their popularity, they exhibit a number of well-documented issues in practice, which apparently contradict theoretical guarantees. A number of enlightening papers have pointed out that these issues arise from unjustified assumptions that are commonly made, but the message seems to
Michele Levi
We report here on a line of work that has played a key role in formally establishing and going beyond the state of the art in the effective field theory (EFT) approach and in post-Newtonian (PN) gravity. We also outline here how this comprehensive framework in fact forms the outset of a prospective rich research program, building on the public Feynman and PN
Fabio Apruzzi, Ling Lin, Christoph Mayrhofer
We initiate the systematic investigation of non-flat resolutions of non-minimal singularities in elliptically fibered Calabi--Yau threefolds. Compactification of M-theory on these geometries provides an alternative approach to studying phases of five-dimensional superconformal field theories (5d SCFTs). We argue that such resolutions capture non-trivial holo
Ákos G. Horváth
The new result of this paper connected with the following problem: Consider a supporting hyperplane of a regular simplex and its re ected image at this hyperplane. When will be the volume of the convex hull of these two simplices maximal? We prove that in the case when the dimension is less or equal to 4, the maximal volume achieves in that case when the hyp
Mohammad Ansari Fard, Sina Taamoli, Shant Baghram
The universe in large scales is structured as a network known as cosmic web. Filaments are one of the structural components of this web, which can be introduced as a novel probe to study the formation and evolution of structures and as a probe to study the cosmological models and to address the missing baryon problem. The aim of this work is to introduce an
Sergio Barrachina-Muñoz, Francesc Wilhelmi, Ioannis Selinis, Boris Bellalta
Komondor is a wireless network simulator for next-generation wireless local area networks (WLANs). The simulator has been conceived as an accessible (ready-to-use) open source tool for research on wireless networks and academia. An important advantage of Komondor over other well-known wireless simulators lies in its high event processing rate, which is furni
Manuel Brea-Carreras, Michael Thiel, Markus Pössel
We report on a project undertaken in Summer 2017 by pre-university student interns at Haus der Astronomie: point-particle simulations of galaxy collisions with the aim of reproducing observational data from such collisions. We succeeded in providing a visually similar representation of both NGC 5426/7 and the "Antennae" galaxies (NGC 4038/9), and were able t
A Physical Picture of Bispectrum Baryon Acoustic Oscillations in the Interferometric Basis
astro-ph.COHillary L. Child, Zachary Slepian, Masahiro Takada
We present a picture of the matter bispectrum in a novel "interferometric" basis designed to highlight interference of the baryon acoustic oscillations (BAO) in the power spectra composing it. Triangles where constructive interference amplifies BAO provide stronger cosmic distance constraints than triangles with destructive interference. We show that the amp
Akhilan Boopathy, Tsui-Wei Weng, Pin-Yu Chen, Sijia Liu
Verifying robustness of neural network classifiers has attracted great interests and attention due to the success of deep neural networks and their unexpected vulnerability to adversarial perturbations. Although finding minimum adversarial distortion of neural networks (with ReLU activations) has been shown to be an NP-complete problem, obtaining a non-trivi
N. Volchanskiy, V. Beylin, V. Kuksa
We study possibilities to extend the Standard Model (SM) by three flavors of vectorlike heavy quarks in pseudoreal representation of symplectic hypercolor gauge group. This extension of SM predicts a rich spectra of heavy composite hypermesons and hyperbaryons (all of them carry integer spins) including fourteen pseudo-Nambu--Goldstone states emerging in dyn
Kaushik P. Seshadreesan, Hari Krovi, Saikat Guha
Quantum repeaters are indispensable for high-rate, long-distance quantum communications. The vision of a future quantum internet strongly hinges on realizing quantum repeaters in practice. Numerous repeaters have been proposed for discrete-variable (DV) single-photon-based quantum communications. Continuous variable (CV) encodings over the quadrature degrees
When Left and Right Turns Inside Out: A Geometric and Categorical Introduction to an Inverse Problem in Persistence
math.ATJustin Curry
In this paper we introduce the problem of counting embedded spheres in R^3 whose projection to the z-axis yields a level set barcode of a particular type. Two embedded spheres are considered height equivalent if they are related by a z-level set preserving isotopy. A formula previously used to count functions on the interval with the same sub-level set persi
Photon Fluence and Dose Estimation in Computed Tomography using a Discrete Ordinates Boltzmann Solver
physics.med-phEdward T. Norris, Xin Liu
In this study, cone-beam single projection and axial CT scans are modeled with a software package - DOCTORS, which solves the linear Boltzmann equation using the discrete ordinates method. Phantoms include a uniform 35 cm diameter water cylinder and a non-uniform abdomen phantom. Series simulations were performed with different simulation parameters, includi
Clifford Cheung, Prashant Saraswat
A hierarchically small weak scale does not generally coincide with enhanced symmetry, but it may still be exceptional with respect to vacuum energy. By analyzing the classical vacuum energy as a function of parameters such as the Higgs mass, we show how near-criticality, i.e. fine-tuning, corresponds universally to boundaries where the vacuum energy transiti
Yusuf Buyukdag, Tony Gherghetta, Andrew S. Miller
We consider a supersymmetric model that uses partial compositeness to explain the fermion mass hierarchy and predict the sfermion mass spectrum. The Higgs and third-generation matter superfields are elementary, while the first two matter generations are composite. Linear mixing between elementary superfields and supersymmetric operators with large anomalous
Josue Nassar, Scott W. Linderman, Monica Bugallo, Il Memming Park
Many real-world systems studied are governed by complex, nonlinear dynamics. By modeling these dynamics, we can gain insight into how these systems work, make predictions about how they will behave, and develop strategies for controlling them. While there are many methods for modeling nonlinear dynamical systems, existing techniques face a trade off between
Joel Clingempeel, Bruno Le Floch, Mauricio Romo
We study how B-branes in two-dimensional N=(2,2) anomalous models behave as we vary the energy scale and bulk parameters in the quantum K\"ahler moduli space. We focus on (2,2) theories defined by abelian gauged linear sigma models (GLSM). Guided by the hemisphere partition function we find how B-branes split in arbitrary phases into components on the Higgs
Carlos E. Navia
Nearby isolated galaxies ($z\sim 0$), are considered immerse within a thermal bath at 2.73 K. However the dwarf galaxies orbiting these galaxies are also subject to additional radiation from their hosts, so they are within a thermal bath slightly warmer. We claim that this thermal effect can explain several properties of the dwarf galaxies, such as their rot
A systematic path to non-Markovian dynamics: New response pdf evolution equations under Gaussian coloured noise excitation
math-phK. I. Mamis, G. A. Athanassoulis, Z. G. Kapelonis
Determining evolution equations governing the probability density function (pdf) of non-Markovian responses to random differential equations (RDEs) excited by coloured noise, is an important issue arising in various problems of stochastic dynamics, advanced statistical physics and uncertainty quantification of macroscopic systems. In the present work, such e
Abigail N. Poteshman, Evelyn Tang, Lia Papadopoulos, Danielle S. Bassett
Mesoscopic quantum systems exhibit complex many-body quantum phenomena, where interactions between spins and charges give rise to collective modes and topological states. Even simple, non-interacting theories display a rich landscape of energy states --- distinct many-particle configurations connected by spin- and energy-dependent transition rates. The colle
Emanuele Ripiccini, Daiki Hayakawa, Giuseppe Iacobucci, Marzio Nessi
The TT-PET collaboration is developing a small animal TOF-PET scanner based on silicon detectors featuring 30 ps RMS time resolution and intended to be inserted in an existing MRI scanner. The TT-PET scanner makes use of a stack of layers of high-Z photon-converter and 100 $\mathrm{\mu m}$ thick silicon sensors, to achieve a scanner with 0.5 $\mathrm{\times}
Steven S. Gubser, Christian Jepsen, Ziming Ji, Brian Trundy
We consider scalar field theory defined over a direct product of the real and $p$-adic numbers. An adjustable dynamical scaling exponent $z$ enters into the microscopic lagrangian, so that the Gaussian theories provide a line of fixed points. We argue that at $z=1/3$, a branch of Wilson-Fisher fixed points joins onto the line of Gaussian theories. We compute
Evolution of magneto-crystalline anisotropies in Mn$_{1-x}$Fe$_x$Si and Mn$_{1-x}$Co$_x$Si as inferred from small-angle neutron scattering and bulk properties
cond-mat.str-elJ. Kindervater, T. Adams, A. Bauer, F. Haslbeck
We report a comprehensive small-angle neutron scattering~(SANS) study of Mn$_{1-x}$Fe$_{x}$Si at zero magnetic field. To delineate changes of magneto-crystalline anisotropies (MCAs) from effects due to defects and disorder, we recorded complementary susceptibility and specific heat data, and investigated selected compositions of Mn$_{1-x}$Co$_{x}$Si. For all