@inproceedings{18261, author = {Tsitsulin, Anton and Mottin, Davide and Karras, Panagiotis and Bronstein, Alexander and Müller, Emmanuel}, booktitle = {Companion Proceedings of The 2019 World Wide Web Conference}, isbn = {9781450366755}, location = {San Francisco, CA, United States}, pages = {308 -- 309}, publisher = {ACM}, title = {{Spectral graph complexity}}, doi = {10.1145/3308560.3316589}, year = {2019}, } @inproceedings{18262, abstract = {This paper explores a fully unsupervised deep learning approach for computing distance-preserving maps that generate low-dimensional embeddings for a certain class of manifolds. We use the Siamese configuration to train a neural network to solve the problem of least squares multidimensional scaling for generating maps that approximately preserve geodesic distances. By training with only a few landmarks, we show a significantly improved local and nonlocal generalization of the isometric mapping as compared to analogous non-parametric counterparts. Importantly, the combination of a deep-learning framework with a multidimensional scaling objective enables a numerical analysis of network architectures to aid in understanding their representation power. This provides a geometric perspective to the generalizability of deep learning.}, author = {Pai, Gautam and Talmon, Ronen and Bronstein, Alexander and Kimmel, Ron}, booktitle = {2019 IEEE Winter Conference on Applications of Computer Vision (WACV)}, isbn = {9781728119762}, location = {Waikoloa, HI, United States}, publisher = {IEEE}, title = {{DIMAL: Deep isometric manifold learning using sparse geodesic sampling}}, doi = {10.1109/wacv.2019.00092}, year = {2019}, } @article{18263, abstract = {We consider the tasks of representing, analysing and manipulating maps between shapes. We model maps as densities over the product manifold of the input shapes; these densities can be treated as scalar functions and therefore are manipulable using the language of signal processing on manifolds. Being a manifold itself, the product space endows the set of maps with a geometry of its own, which we exploit to define map operations in the spectral domain; we also derive relationships with other existing representations (soft maps and functional maps). To apply these ideas in practice, we discretize product manifolds and their Laplace–Beltrami operators, and we introduce localized spectral analysis of the product manifold as a novel tool for map processing. Our framework applies to maps defined between and across 2D and 3D shapes without requiring special adjustment, and it can be implemented efficiently with simple operations on sparse matrices.}, author = {Rodolà, E. and Lähner, Z. and Bronstein, Alexander and Bronstein, M. M. and Solomon, J.}, issn = {1467-8659}, journal = {Computer Graphics Forum}, number = {1}, pages = {678--689}, publisher = {Wiley}, title = {{Functional maps representation on product manifolds}}, doi = {10.1111/cgf.13598}, volume = {38}, year = {2019}, } @article{18264, abstract = {We present DeepISP, a full end-to-end deep neural model of the camera image signal processing pipeline. Our model learns a mapping from the raw low-light mosaiced image to the final visually compelling image and encompasses low-level tasks, such as demosaicing and denoising, as well as higher-level tasks, such as color correction and image adjustment. The training and evaluation of the pipeline were performed on a dedicated data set containing pairs of low-light and well-lit images captured by a Samsung S7 smartphone camera in both raw and processed JPEG formats. The proposed solution achieves the state-of-the-art performance in objective evaluation of peak signal-to-noise ratio on the subtask of joint denoising and demosaicing. For the full end-to-end pipeline, it achieves better visual quality compared to the manufacturer ISP, in both a subjective human assessment and when rated by a deep model trained for assessing image quality.}, author = {Schwartz, Eli and Giryes, Raja and Bronstein, Alexander}, issn = {1057-7149}, journal = {IEEE Transactions on Image Processing}, number = {2}, pages = {912--923}, publisher = {Institute of Electrical and Electronics Engineers}, title = {{DeepISP: Toward learning an end-to-end image processing pipeline}}, doi = {10.1109/tip.2018.2872858}, volume = {28}, year = {2019}, } @inproceedings{18268, abstract = {The registration of surfaces with non-rigid deformation, especially non-isometric deformations, is a challenging problem. When applying such techniques to real scans, the problem is compounded by topological and geometric inconsistencies between shapes. In this paper, we capture a benchmark dataset of scanned 3D shapes undergoing various controlled deformations (articulating, bending, stretching and topologically changing), along with ground truth correspondences. With the aid of this tiered benchmark of increasingly challenging real scans, we explore this problem and investigate how robust current state-of- the-art methods perform in different challenging registration and correspondence scenarios. We discover that changes in topology is a challenging problem for some methods and that machine learning-based approaches prove to be more capable of handling non-isometric deformations on shapes that are moderately similar to the training set.}, author = {Dyke, R.M. and Stride, C. and Lai, Y.-K. and Rosin, P.L. and Aubry, M. and Boyarski, A. and Bronstein, Alexander and Bronstein, M.M. and Cremers, D. and Fisher, M. and Groueix, T. and Guo, D. and Kim, V.G. and Kimmel, R. and Lähner, Z. and Li, K. and Litany, O. and Remez, T. and Rodola, E. and Russell, B.C. and Sahillioglu, Y. and Slossberg, R. and Tam, G.K.L. and Vestner, M. and Wu, Z. and Yang, J.}, booktitle = {Eurographics Workshop on 3D Object Retrieval}, issn = {1997-0471}, publisher = {The Eurographics Association}, title = {{Shape correspondence with isometric and non-isometric deformations}}, doi = {10.2312/3DOR.20191069}, year = {2019}, } @inproceedings{18269, abstract = {In the past few years, deep learning-based methods have demonstrated enormous success for solving inverse problems in medical imaging. In this work, we address the following question: Given a set of measurements obtained from real imaging experiments, what is the best way to use a learnable model and the physics of the modality to solve the inverse problem and reconstruct the latent image? Standard supervised learning based methods approach this problem by collecting data sets of known latent images and their corresponding measurements. However, these methods are often impractical due to the lack of availability of appropriately sized training sets, and, more generally, due to the inherent difficulty in measuring the “groundtruth” latent image. In light of this, we propose a self-supervised approach to training inverse models in medical imaging in the absence of aligned data. Our method only requiring access to the measurements and the forward model at training. We showcase its effectiveness on inverse problems arising in accelerated magnetic resonance imaging (MRI). }, author = {Senouf, Ortal and Vedula, Sanketh and Weiss, Tomer and Bronstein, Alexander and Michailovich, Oleg and Zibulevsky, Michael}, booktitle = {First MICCAI Workshop, DART 2019, and First International Workshop, MIL3ID 2019}, isbn = {9783030333904}, issn = {1611-3349}, location = {Shenzhen, China}, pages = {111 -- 119}, publisher = {Springer International Publishing}, title = {{Self-supervised learning of inverse problem solvers in medical imaging}}, doi = {10.1007/978-3-030-33391-1_13}, volume = {11795}, year = {2019}, } @article{22048, abstract = {We prove symplectic non-squeezing for the cubic nonlinear Schrödinger equation on the line via finite-dimensional approximation.}, author = {Killip, Rowan and Visan, Monica and Zhang, Xiaoyi}, issn = {1687-0247}, journal = {International Mathematics Research Notices}, number = {5}, pages = {1312--1332}, publisher = {Oxford University Press}, title = {{Symplectic non-squeezing for the cubic NLS on the line}}, doi = {10.1093/imrn/rnx152}, volume = {2019}, year = {2019}, } @article{22066, abstract = {We prove almost sure global existence and scattering for the energy-critical nonlinear Schrödinger equation with randomized spherically symmetric initial data in 𝐻𝑠⁡(ℝ4) with 5/6<𝑠<1. We were inspired to consider this problem by the recent work of Dodson–Lührmann–Mendelson, which treated the analogous problem for the energy-critical wave equation.}, author = {Killip, Rowan and Murphy, Jason and Visan, Monica}, issn = {1532-4133}, journal = {Communications in Partial Differential Equations}, number = {1}, pages = {51--71}, publisher = {Informa UK Limited}, title = {{Almost sure scattering for the energy-critical NLS with radial data below H1(R4)}}, doi = {10.1080/03605302.2018.1541904}, volume = {44}, year = {2019}, } @article{22077, abstract = {We prove inverse Strichartz theorems at L^2 regularity for a family of Schrödinger evolutions in one space dimension. Prior results rely on spacetime Fourier analysis and are limited to the translation-invariant equation i∂ t​ u=−1/2 Δu. Motivated by applications to the mass-critical Schrödinger equation with external potentials (such as the harmonic oscillator), we use a physical space approach.}, author = {Jao, Casey and Killip, Rowan and Visan, Monica}, issn = {2235-0616}, journal = {Revista Matemática Iberoamericana}, number = {3}, pages = {703--730}, publisher = {European Mathematical Society Press}, title = {{Mass-critical inverse Strichartz theorems for 1d Schrödinger operators}}, doi = {10.4171/rmi/1067}, volume = {35}, year = {2019}, } @article{10879, abstract = {We study effects of a bounded and compactly supported perturbation on multidimensional continuum random Schrödinger operators in the region of complete localisation. Our main emphasis is on Anderson orthogonality for random Schrödinger operators. Among others, we prove that Anderson orthogonality does occur for Fermi energies in the region of complete localisation with a non-zero probability. This partially confirms recent non-rigorous findings [V. Khemani et al., Nature Phys. 11 (2015), 560–565]. The spectral shift function plays an important role in our analysis of Anderson orthogonality. We identify it with the index of the corresponding pair of spectral projections and explore the consequences thereof. All our results rely on the main technical estimate of this paper which guarantees separate exponential decay of the disorder-averaged Schatten p-norm of χa(f(H)−f(Hτ))χb in a and b. Here, Hτ is a perturbation of the random Schrödinger operator H, χa is the multiplication operator corresponding to the indicator function of a unit cube centred about a∈Rd, and f is in a suitable class of functions of bounded variation with distributional derivative supported in the region of complete localisation for H.}, author = {Dietlein, Adrian M and Gebert, Martin and Müller, Peter}, issn = {1664-039X}, journal = {Journal of Spectral Theory}, keywords = {Random Schrödinger operators, spectral shift function, Anderson orthogonality}, number = {3}, pages = {921--965}, publisher = {EMS Press}, title = {{Perturbations of continuum random Schrödinger operators with applications to Anderson orthogonality and the spectral shift function}}, doi = {10.4171/jst/267}, volume = {9}, year = {2019}, } @article{439, abstract = {We count points over a finite field on wild character varieties,of Riemann surfaces for singularities with regular semisimple leading term. The new feature in our counting formulas is the appearance of characters of Yokonuma–Hecke algebras. Our result leads to the conjecture that the mixed Hodge polynomials of these character varieties agree with previously conjectured perverse Hodge polynomials of certain twisted parabolic Higgs moduli spaces, indicating the possibility of a P = W conjecture for a suitable wild Hitchin system.}, author = {Hausel, Tamas and Mereb, Martin and Wong, Michael}, issn = {1435-9855}, journal = {Journal of the European Mathematical Society}, number = {10}, pages = {2995--3052}, publisher = {EMS Press}, title = {{Arithmetic and representation theory of wild character varieties}}, doi = {10.4171/JEMS/896}, volume = {21}, year = {2019}, } @misc{9726, abstract = {A detailed description of the two stochastic models, table of parameters, supplementary data for Figures 4 and 5, parameter dependence of the results, and an analysis on motors with different force–velocity functions (PDF)}, author = {Ucar, Mehmet C and Lipowsky, Reinhard}, publisher = {American Chemical Society}, title = {{Supplementary information - Collective force generation by molecular motors is determined by strain-induced unbinding}}, doi = {10.1021/acs.nanolett.9b04445.s001}, year = {2019}, } @article{6986, abstract = {Li-Nadler proposed a conjecture about traces of Hecke categories, which implies the semistable part of the Betti geometric Langlands conjecture of Ben-Zvi-Nadler in genus 1. We prove a Weyl group analogue of this conjecture. Our theorem holds in the natural generality of reflection groups in Euclidean or hyperbolic space. As a corollary, we give an expression of the centralizer of a finite order element in a reflection group using homotopy theory. }, author = {Li, Penghui}, issn = {1088-6826}, journal = {Proceedings of the American Mathematical Society}, number = {11}, pages = {4597--4604}, publisher = {American Mathematical Society}, title = {{A colimit of traces of reflection groups}}, doi = {10.1090/proc/14586}, volume = {147}, year = {2019}, } @article{6050, abstract = {We answer a question of David Hilbert: given two circles it is not possible in general to construct their centers using only a straightedge. On the other hand, we give infinitely many families of pairs of circles for which such construction is possible. }, author = {Akopyan, Arseniy and Fedorov, Roman}, journal = {Proceedings of the American Mathematical Society}, pages = {91--102}, publisher = {American Mathematical Society}, title = {{Two circles and only a straightedge}}, doi = {10.1090/proc/14240}, volume = {147}, year = {2019}, } @article{6029, abstract = {Protein micropatterning has become an important tool for many biomedical applications as well as in academic research. Current techniques that allow to reduce the feature size of patterns below 1 μm are, however, often costly and require sophisticated equipment. We present here a straightforward and convenient method to generate highly condensed nanopatterns of proteins without the need for clean room facilities or expensive equipment. Our approach is based on nanocontact printing and allows for the fabrication of protein patterns with feature sizes of 80 nm and periodicities down to 140 nm. This was made possible by the use of the material X-poly(dimethylsiloxane) (X-PDMS) in a two-layer stamp layout for protein printing. In a proof of principle, different proteins at various scales were printed and the pattern quality was evaluated by atomic force microscopy (AFM) and super-resolution fluorescence microscopy.}, author = {Lindner, Marco and Tresztenyak, Aliz and Fülöp, Gergö and Jahr, Wiebke and Prinz, Adrian and Prinz, Iris and Danzl, Johann G and Schütz, Gerhard J. and Sevcsik, Eva}, issn = {2296-2646}, journal = {Frontiers in Chemistry}, publisher = {Frontiers Media}, title = {{A fast and simple contact printing approach to generate 2D protein nanopatterns}}, doi = {10.3389/fchem.2018.00655}, volume = {6}, year = {2019}, } @article{5886, abstract = {Problems involving quantum impurities, in which one or a few particles are interacting with a macroscopic environment, represent a pervasive paradigm, spanning across atomic, molecular, and condensed-matter physics. In this paper we introduce new variational approaches to quantum impurities and apply them to the Fröhlich polaron–a quasiparticle formed out of an electron (or other point-like impurity) in a polar medium, and to the angulon–a quasiparticle formed out of a rotating molecule in a bosonic bath. We benchmark these approaches against established theories, evaluating their accuracy as a function of the impurity-bath coupling.}, author = {Li, Xiang and Bighin, Giacomo and Yakaboylu, Enderalp and Lemeshko, Mikhail}, issn = {0026-8976}, journal = {Molecular Physics}, publisher = {Taylor & Francis}, title = {{Variational approaches to quantum impurities: from the Fröhlich polaron to the angulon}}, doi = {10.1080/00268976.2019.1567852}, year = {2019}, } @article{5680, abstract = {Pollinators display a remarkable diversity of foraging strategies with flowering plants, from primarily mutualistic interactions to cheating through nectar robbery. Despite numerous studies on the effect of nectar robbing on components of plant fitness, its contribution to reproductive isolation is unclear. We experimentally tested the impact of different pollinator strategies in a natural hybrid zone between two subspecies of Antirrhinum majus with alternate flower colour guides. On either side of a steep cline in flower colour between Antirrhinum majus pseudomajus (magenta) and A. m. striatum (yellow), we quantified the behaviour of all floral visitors at different time points during the flowering season. Using long-run camera surveys, we quantify the impact of nectar robbing on the number of flowers visited per inflorescence and the flower probing time. We further experimentally tested the effect of nectar robbing on female reproductive success by manipulating the intensity of robbing. While robbing increased over time the number of legitimate visitors tended to decrease concomitantly. We found that the number of flowers pollinated on a focal inflorescence decreased with the number of prior robbing events. However, in the manipulative experiment, fruit set and fruit volume did not vary significantly between low robbing and control treatments. Our findings challenge the idea that robbers have a negative impact on plant fitness through female function. This study also adds to our understanding of the components of pollinator-mediated reproductive isolation and the maintenance of Antirrhinum hybrid zones.}, author = {Andalo, Christophe and Burrus, Monique and Paute, Sandrine and Lauzeral, Christine and Field, David}, issn = {2381-8115}, journal = {Botany Letters}, number = {1}, pages = {80--92}, publisher = {Taylor & Francis}, title = {{Prevalence of legitimate pollinators and nectar robbers and the consequences for fruit set in an Antirrhinum majus hybrid zone}}, doi = {10.1080/23818107.2018.1545142}, volume = {166}, year = {2019}, } @article{6657, abstract = {In this article a model is described how Open Access definitions can be formed on the basis of objective criteria. The common Open Access definitions such as "gold" and "green" are not exactly defined. This becomes a problem as soon as one begins to measure Open Access, for example if the development of the Open Access share should be monitored. This was discussed in the working group on Open Access Monitoring of the AT2OA project and the present model was developed, which is based on 5 critics with 4 characteristics: location, licence, version, embargo and conditions of the Open Access publication are taken into account. In the meantime, the model has also been tested in practice using R scripts, and the initial results are quite promising.}, author = {Danowski, Patrick}, issn = {1022-2588}, journal = {Mitteilungen der Vereinigung Österreichischer Bibliothekarinnen und Bibliothekare}, number = {1}, pages = {59--65}, publisher = {Vereinigung Österreichischer Bibliothekarinnen und Bibliothekare}, title = {{An Austrian proposal for the classification of Open Access Tuples (COAT) - distinguish different open access types beyond colors}}, doi = {10.31263/voebm.v72i1.2276}, volume = {72}, year = {2019}, } @inproceedings{6822, abstract = {In two-player games on graphs, the players move a token through a graph to produce an infinite path, which determines the qualitative winner or quantitative payoff of the game. In bidding games, in each turn, we hold an auction between the two players to determine which player moves the token. Bidding games have largely been studied with concrete bidding mechanisms that are variants of a first-price auction: in each turn both players simultaneously submit bids, the higher bidder moves the token, and pays his bid to the lower bidder in Richman bidding, to the bank in poorman bidding, and in taxman bidding, the bid is split between the other player and the bank according to a predefined constant factor. Bidding games are deterministic games. They have an intriguing connection with a fragment of stochastic games called randomturn games. We study, for the first time, a combination of bidding games with probabilistic behavior; namely, we study bidding games that are played on Markov decision processes, where the players bid for the right to choose the next action, which determines the probability distribution according to which the next vertex is chosen. We study parity and meanpayoff bidding games on MDPs and extend results from the deterministic bidding setting to the probabilistic one.}, author = {Avni, Guy and Henzinger, Thomas A and Ibsen-Jensen, Rasmus and Novotny, Petr}, booktitle = {Proceedings of the 13th International Conference of Reachability Problems}, isbn = {978-303030805-6}, issn = {0302-9743}, location = {Brussels, Belgium}, pages = {1--12}, publisher = {Springer}, title = {{Bidding games on Markov decision processes}}, doi = {10.1007/978-3-030-30806-3_1}, volume = {11674}, year = {2019}, } @inproceedings{6528, abstract = {We construct a verifiable delay function (VDF) by showing how the Rivest-Shamir-Wagner time-lock puzzle can be made publicly verifiable. Concretely, we give a statistically sound public-coin protocol to prove that a tuple (N,x,T,y) satisfies y=x2T (mod N) where the prover doesn’t know the factorization of N and its running time is dominated by solving the puzzle, that is, compute x2T, which is conjectured to require T sequential squarings. To get a VDF we make this protocol non-interactive using the Fiat-Shamir heuristic.The motivation for this work comes from the Chia blockchain design, which uses a VDF as akey ingredient. For typical parameters (T≤2 40, N= 2048), our proofs are of size around 10K B, verification cost around three RSA exponentiations and computing the proof is 8000 times faster than solving the puzzle even without any parallelism.}, author = {Pietrzak, Krzysztof Z}, booktitle = {10th Innovations in Theoretical Computer Science Conference}, isbn = {978-3-95977-095-8}, issn = {1868-8969}, location = {San Diego, CA, United States}, publisher = {Schloss Dagstuhl - Leibniz-Zentrum für Informatik}, title = {{Simple verifiable delay functions}}, doi = {10.4230/LIPICS.ITCS.2019.60}, volume = {124}, year = {2019}, }