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What else can be said about star formation rate indicators that has not been said already many times over? The `coming of age' of large ground-based surveys and the unprecedented sensitivity, angular resolution and/or field-of-view of…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-16 Daniela Calzetti

Robustness against small perturbations is a crucial feature of topological properties. This robustness is both a source of theoretical interest and a drive for technological applications, but presents a challenge when looking for new…

Mesoscale and Nanoscale Physics · Physics 2021-01-04 Cyrill Bösch , Tena Dubček , Frank Schindler , Andreas Fichtner , Marc Serra-Garcia

We present and test a new halo finder based on the spherical overdensity (SO) method. This new adaptive spherical overdensity halo finder (ASOHF) is able to identify dark matter haloes and their substructures (subhaloes) down to the scales…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Susana Planelles , Vicent Quilis

This paper proposes the application of some well known two-dimensional geometrical shape descriptors for the visualisation of the structure of architectural open spaces. The paper demonstrates the use of visibility measures such as distance…

Computer Vision and Pattern Recognition · Computer Science 2007-05-23 Sanjay Rana , Mike Batty

Suppose we have identified three clusters of galaxies as being topological copies of the same object. How does this information constrain the possible models for the shape of our Universe? It is shown here that, if the Universe has flat…

Astrophysics · Physics 2009-11-07 G. I. Gomero

Structural quantities such as order parameters and correlation functions are often employed to gain insight into the physical behavior and properties of condensed matter systems. While standard quantities for characterizing structure exist,…

Soft Condensed Matter · Physics 2017-08-23 Aaron S. Keys , Christopher R. Iacovella , Sharon C. Glotzer

The morphology of a disk galaxy is closely linked to its kinematic state. This is because density wave features are likely made of spontaneously-formed modes which are allowed to arise in the galactic resonant cavity of a particular basic…

Astrophysics · Physics 2008-12-17 R. Buta , X. Zhang

We study scattering by metamaterials with negative indices of refraction, which are known to support \emph{surface plasmons} -- long-lived states that are highly localized at the boundary of the cavity. This type of states has found uses in…

Spectral Theory · Mathematics 2025-05-29 Yan-Long Fang , Jeffrey Galkowski

What is the shape of the Universe? Is it curved or flat, finite or infinite ? Is space "wrapped around" to create ghost images of faraway cosmic sources? We review how tessellations allow to build multiply-connected 3D Riemannian spaces…

Astrophysics · Physics 2008-02-18 Jean-Pierre Luminet

Galaxy evolution is driven to a large extent by interactions and mergers with other galaxies and the gas in galaxies is extremely sensitive to the interactions. One method to measure such interactions uses the quantified morphology of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 B. W. Holwerda , N. Pirzkal , W. J. G. de Blok , A. Bouchard , S-L. Blyth , K. J. van der Heyden , E. C. Elson

We present ShapeFormer, a transformer-based network that produces a distribution of object completions, conditioned on incomplete, and possibly noisy, point clouds. The resultant distribution can then be sampled to generate likely…

Computer Vision and Pattern Recognition · Computer Science 2022-05-24 Xingguang Yan , Liqiang Lin , Niloy J. Mitra , Dani Lischinski , Daniel Cohen-Or , Hui Huang

We consider the problem of establishing dense correspondences within a set of related shapes of strongly varying geometry. For such input, traditional shape matching approaches often produce unsatisfactory results. We propose an ensemble…

Graphics · Computer Science 2017-10-10 Oliver Burghard , Alexander Berner , Michael Wand , Niloy Mitra , Hans-Peter Seidel , Reinhard Klein

We construct algorithms and topological invariants that allow us to distinguish the topological type of a surface, as well as functions and vector fields for their topological equivalence. In the first part (arXiv:2501.15657), we discused…

Geometric Topology · Mathematics 2025-02-17 Alexandr Prishlyak

The shapelets method for image analysis is based upon the decomposition of localised objects into a series of orthogonal components with convenient mathematical properties. We extend the "Cartesian shapelet" formalism from earlier work, and…

Astrophysics · Physics 2009-11-10 Richard Massey , Alexandre Refregier

Galaxy morphology is a fundamental quantity, that is essential not only for the full spectrum of galaxy-evolution studies, but also for a plethora of science in observational cosmology. While a rich literature exists on…

Astrophysics of Galaxies · Physics 2020-01-08 Garreth Martin , Sugata Kaviraj , Alex Hocking , Shaun C. Read , James E. Geach

The space-like hypersurface of the Universe at the present cosmological time is a three-dimensional manifold. A non-trivial global topology of this space-like hypersurface would imply that the apparently observable universe (the sphere of…

Astrophysics · Physics 2011-04-15 Boudewijn F. Roukema , Vincent Blanloeil

The exciting discovery of topological condensed matter systems has lately triggered a search for their photonic analogs, motivated by the possibility of robust backscattering-immune light transport. However, topological photonic phases have…

To understand the universe and to interpret the cosmological parameters governing its evolution it is necessary to contrast the data from galaxy surveys with simulation. Typically it entails using computationally expensive N -body…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-02 Tolga Yapici , Zachery Brown , Regina Demina , Segev BenZvi

We demonstrate a new multi-wavelength technique for two-dimensional parametric modelling of galaxy surface-brightness profiles, which we have incorporated into the widely used software GALFIT. Our new method, named GALFITM, extends…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Marina Vika , Steven P. Bamford , Boris Haeussler , Alex L. Rojas , Andrea Borch , Robert C. Nichol

Visible and infrared photons can be detected with a broadband response via the internal photoeffect. By using plasmonic nanostructures, i.e. nanoantennas, wavelength selectivity can be introduced to such detectors through geometry-dependent…