5
5.0

audio

#
eye 5

#
favorite 0

#
comment 0

Topics: Radio Program, Republics, Divided regions, Skiing, Northern Europe, Western Europe, East Asian...

4
4.0

audio

#
eye 4

#
favorite 0

#
comment 0

Topics: Radio Program, Divided regions, Republics, Member states of the United Nations, Lines of latitude,...

4
4.0

audio

#
eye 4

#
favorite 0

#
comment 0

Topics: Radio Program, Elementary mathematics, Family, Occupational safety and health, Social networking...

7
7.0

audio

#
eye 7

#
favorite 0

#
comment 0

Topics: Radio Program, NPR personalities, Political science, Conservative Party (UK) MPs, Tropical cyclone...

5
5.0

audio

#
eye 5

#
favorite 0

#
comment 0

Topics: Radio Program, BBC Local Radio, English cricketers, English voice actors, Christmas food, Officers...

5
5.0

audio

#
eye 5

#
favorite 0

#
comment 0

09:00:00AM-12:00:00PM GMT — Mornings With Kaye Adams Kaye Adams asks would you pay to go under the knife to lose weight?

Topics: Radio Program, Obesity, Bariatrics, Nutrition, Dietetics, Symptoms and signs: General, Digestive...

6
6.0

audio

#
eye 6

#
favorite 0

#
comment 0

03:00:00PM-03:06:00PM GMT — BBC News 2019/12/05 15:01 GMT 03:06:00PM-03:30:00PM GMT — The Inquiry Can we protect our elections from social media manipulators? 03:30:00PM-03:32:00PM GMT — BBC News Summary 2019/12/05 15:30 GMT 03:32:00PM-04:00:00PM GMT — World Business Report First broadcast 2019/12/05 15:32 GMT

Topics: Radio Program, Mass media, English language, Organizations awarded Nobel Peace Prizes, Nobel Peace...

6
6.0

audio

#
eye 6

#
favorite 0

#
comment 0

Topics: Radio Program, Republics, Sunday, Former British colonies, Premier League players, Member states of...

6
6.0

Jun 30, 2018
06/18

by
Kai Gao; Shubin Fu; Richard L. Gibson; Eric T. Chung; Yalchin Efendiev

texts

#
eye 6

#
favorite 0

#
comment 0

It is important to develop fast yet accurate numerical methods for seismic wave propagation to characterize complex geological structures and oil and gas reservoirs. However, the computational cost of conventional numerical modeling methods, such as finite-difference method and finite-element method, becomes prohibitively expensive when applied to very large models. We propose a Generalized Multiscale Finite-Element Method (GMsFEM) for elastic wave propagation in heterogeneous, anisotropic...

Topics: Physics, Mathematics, Numerical Analysis, Geophysics

Source: http://arxiv.org/abs/1409.3550

3
3.0

Jun 30, 2018
06/18

by
Daniel Plaumann; Mihai Putinar

texts

#
eye 3

#
favorite 0

#
comment 0

We study the pullback of the apolarity invariant of complex polynomials in one variable under a polynomial map on the complex plane. As a consequence, we obtain variations of the classical results of Grace and Walsh in which the unit disk, or a circular domain, is replaced by its image under the given polynomial map.

Topics: Complex Variables, Mathematics, Algebraic Geometry

Source: http://arxiv.org/abs/1410.5935

4
4.0

Jun 29, 2018
06/18

by
Xiaofeng Xue; Yu Pan

texts

#
eye 4

#
favorite 0

#
comment 0

In this paper we are concerned with the contact process with random recovery rates and edge weights on complete graph with $n$ vertices. We show that the model has a critical value which is inversely proportional to the product of the mean of the edge weight and the mean of the inverse of the recovery rate. In the subcritical case, the process dies out before a moment with order $O(\log n)$ with high probability as $n\rightarrow+\infty$. In the supercritical case, the process survives at a...

Topics: Probability, Mathematics

Source: http://arxiv.org/abs/1607.07933

1
1.0

Jun 29, 2018
06/18

by
Nguyen Thac Dung; Kieu Thi Thuy Linh; Ninh Van Thu

texts

#
eye 1

#
favorite 0

#
comment 0

In this paper, we consider the following general evolution equation $$ u_t=\Delta_fu+au\log^\alpha u+bu $$ on smooth metric measure spaces $(M^n, g, e^{-f}dv)$. We give a local gradient estimate of Souplet-Zhang type for positive smooth solution of this equation provided that the Bakry-\'{E}mery curvature bounded from below. When $f$ is constant, we investigate the gereral evolution on compact Riemannian manifolds with no nconvex boundary satisfying an "\emph{interior rolling...

Topics: Differential Geometry, Mathematics

Source: http://arxiv.org/abs/1610.03198

Topics: Radio Program, Insurance, Crops, Republics, Divided regions, Banking, Member states of the United...

4
4.0

audio

#
eye 4

#
favorite 0

#
comment 0

Topics: Radio Program, Physical exercise, Training, Military, Injuries, Elementary mathematics

4
4.0

audio

#
eye 4

#
favorite 0

#
comment 0

Hello to Jason Isaacs Jason Isaacs talks about The Infiltrator. Plus the week's film reviews.

Topics: BBC, Radio Program, Kermode and Mayo's Film Review, American male actors, Actors from California,...

Source: http://www.bbc.co.uk/programmes/b07q1z36

3
3.0

Jun 30, 2018
06/18

by
Attila Maróti

texts

#
eye 3

#
favorite 0

#
comment 0

Every finite group whose order is divisible by a prime $p$ has at least $2 \sqrt{p-1}$ conjugacy classes.

Topics: Mathematics, Group Theory

Source: http://arxiv.org/abs/1411.0454

3
3.0

Jun 30, 2018
06/18

by
Tobias Kloos

texts

#
eye 3

#
favorite 0

#
comment 0

We study the Zak transform of totally positive (TP) functions. We use the convergence of the Zak transform of TP functions of finite type to prove that the Zak transforms of all TP functions without Gaussian factor in the Fourier transform have only one zero in their fundamental domain of quasi-periodicity. Our proof is based on complex analysis, especially the Theorem of Hurwitz and some real analytic arguments, where we use the connection of TP functions of finite type and exponential...

Topics: Mathematics, Numerical Analysis

Source: http://arxiv.org/abs/1411.1539

6
6.0

Jun 30, 2018
06/18

by
Michal Botur; Anatolij Dvurečenskij

texts

#
eye 6

#
favorite 0

#
comment 0

We study the class of pseudo BL-algebras whose every maximal filter is normal. We present an equational base for this class and we extend these results for the class of basic pseudo hoops with fixed strong unit.

Topics: Mathematics, Rings and Algebras

Source: http://arxiv.org/abs/1412.2253

12
12

Jun 27, 2018
06/18

by
G. Fuhrmann; M. Gröger; T. Jäger

texts

#
eye 12

#
favorite 0

#
comment 0

We introduce amorphic complexity as a new topological invariant that measures the complexity of dynamical systems in the regime of zero entropy. Its main purpose is to detect the very onset of disorder in the asymptotic behaviour. For instance, it gives positive value to Denjoy examples on the circle and Sturmian subshifts, while being zero for all isometries and Morse-Smale systems. After discussing basic properties and examples, we show that amorphic complexity and the underlying asymptotic...

Topics: Mathematics, Dynamical Systems

Source: http://arxiv.org/abs/1503.01036

3
3.0

Jun 28, 2018
06/18

by
Vlad Bally; Arturo Kohatsu-Higa

texts

#
eye 3

#
favorite 0

#
comment 0

In this article, we introduce the parametrix technique in order to construct fundamental solutions as a general method based on semigroups and their generators. This leads to a probabilistic interpretation of the parametrix method that is amenable to Monte Carlo simulation. We consider the explicit examples of continuous diffusions and jump driven stochastic differential equations with H\"{o}lder continuous coefficients.

Topics: Probability, Mathematics

Source: http://arxiv.org/abs/1510.06909

4
4.0

Jun 28, 2018
06/18

by
Attila Lovas; Róbert Nagy; Elek Csobo; Brigitta Szilágyi; Péter Sótonyi

texts

#
eye 4

#
favorite 0

#
comment 0

We present a novel numerical algorithm developed to reconstuct pulsatile blood flow from ECG-gated CT angiography data. A block-based optimization method was constructed to solve the inverse problem corresponding to the Riccati-type ordinary differential equation that can be deduced from conservation principles and Hooke's law. Local flow rate for 5 patients was computed in 10cm long aorta segments that are located 1cm below the heart. The wave form of the local flow rate curves seems to be...

Topics: Physics, Numerical Analysis, Mathematics, Medical Physics

Source: http://arxiv.org/abs/1511.08021

4
4.0

Jun 28, 2018
06/18

by
Peter J. McNamara; Peter Tingley

texts

#
eye 4

#
favorite 0

#
comment 0

Simple representations of KLR algebras can be used to realize the infinity crystal for the corresponding symmetrizable Kac-Moody algebra. It was recently shown that, in finite and affine types, certain sub-categories of cuspidal representations realize crystals for sub Kac-Moody algebras. Here we put that observation an a firmer categorical footing by exhibiting a functor between the category of representations of the KLR algebra for the sub Kac-Moody algebra and the category of cuspidal...

Topics: Quantum Algebra, Representation Theory, Mathematics

Source: http://arxiv.org/abs/1512.04458

4
4.0

Jun 28, 2018
06/18

by
P. G. Grinevich; R. G. Novikov

texts

#
eye 4

#
favorite 0

#
comment 0

We continue studies of Moutard-type transforms for the generalized analytic functions started in arXiv:1510.08764, arXiv:1512.00343. In particular, we show that generalized analytic functions with the simplest contour poles can be Moutard transformed to the regular ones, at least, locally. In addition, the later Moutard-type transforms are locally invertible.

Topics: Mathematics, Functional Analysis, Complex Variables, Exactly Solvable and Integrable Systems,...

Source: http://arxiv.org/abs/1512.08874

3
3.0

Jun 29, 2018
06/18

by
Jiayu Li; Chuanjing Zhang; Xi Zhang

texts

#
eye 3

#
favorite 0

#
comment 0

In this paper, we study semistable Higgs sheaves over compact K\"ahler manifolds, we prove that there is an approximate admissible Hermitian-Einstein structure on a semi-stable reflexive Higgs sheaf and consequently, the Bogomolove type inequality holds on a semi-stable reflexive Higgs sheaf.

Topics: Differential Geometry, Mathematics

Source: http://arxiv.org/abs/1601.00729

3
3.0

Jun 29, 2018
06/18

by
Cristina Butucea; Rania Zgheib

texts

#
eye 3

#
favorite 0

#
comment 0

We observe $n$ independent $p-$dimensional Gaussian vectors with missing coordinates, that is each value (which is assumed standardized) is observed with probability $a>0$. We investigate the problem of minimax nonparametric testing that the high-dimensional covariance matrix $\Sigma$ of the underlying Gaussian distribution is the identity matrix, using these partially observed vectors. Here, $n$ and $p$ tend to infinity and $a>0$ tends to 0, asymptotically. We assume that $\Sigma$...

Topics: Statistics, Statistics Theory, Mathematics

Source: http://arxiv.org/abs/1602.04310

4
4.0

Jun 29, 2018
06/18

by
K. Ito; E. Skibsted

texts

#
eye 4

#
favorite 0

#
comment 0

We show an optimal version of the Rellich theorem for generalized many-body Schrodinger operators. It applies to singular potentials, in particular to a model for atoms and molecules with infinite mass and finite extent nuclei. Our proof relies on a Mourre estimate and a functional calculus localization technique.

Topics: Functional Analysis, Mathematical Physics, Mathematics

Source: http://arxiv.org/abs/1602.07493

4
4.0

Jun 29, 2018
06/18

by
Pierre Degond; Silke Henkes; Hui Yu

texts

#
eye 4

#
favorite 0

#
comment 0

Motivated by recent experimental and computational results that show a motility-induced clustering transition in self-propelled particle systems, we study an individual model and its corresponding Self-Organized Hydrodynamic model for collective behaviour that incorporates a density-dependent velocity, as well as inter-particle alignment. The modal analysis of the hydrodynamic model elucidates the relationship between the stability of the equilibria and the changing velocity, and the formation...

Topics: Numerical Analysis, Nonlinear Sciences, Mathematical Physics, Adaptation and Self-Organizing...

Source: http://arxiv.org/abs/1602.06195

4
4.0

Jun 29, 2018
06/18

by
Xiaolu Hou

texts

#
eye 4

#
favorite 0

#
comment 0

We study ideal lattices constructed from totally definite quaternion algebras over totally real number fields, and generalize the definition of Arakelov-modular lattices over number fields. In particular, we prove for the case where the totally real number field is $\mathbb{Q}$, that for $\ell$ a prime integer, there always exists a totally definite quaternion over $\mathbb{Q}$ from which an Arakelov-modular lattice of level $\ell$ can be constructed.

Topics: Rings and Algebras, Mathematics

Source: http://arxiv.org/abs/1604.02875

7
7.0

Jun 29, 2018
06/18

by
R. Garra; E. Orsingher; M. Scavino

texts

#
eye 7

#
favorite 0

#
comment 0

This paper studies the first hitting times of generalized Poisson processes $N^f(t)$, related to Bernstein functions $f$. For the space-fractional Poisson processes, $N^\alpha(t)$, $t>0$ (corresponding to $f= x^\alpha$), the hitting probabilities $P\{T_k^\alpha

Topics: Probability, Mathematics

Source: http://arxiv.org/abs/1604.05235

3
3.0

Jun 29, 2018
06/18

by
I. A. Taimanov

texts

#
eye 3

#
favorite 0

#
comment 0

We calculate the rational equivariant cohomology of the spaces of non-contractible loops in compact space forms and show how to apply these calculations for proving the existence of closed geodesics.

Topics: Differential Geometry, Geometric Topology, Mathematics

Source: http://arxiv.org/abs/1604.05237

5
5.0

Jun 29, 2018
06/18

by
Alexei Borodin; Vadim Gorin

texts

#
eye 5

#
favorite 0

#
comment 0

The results of Amir-Corwin-Quastel, Calabrese-Le Doussal-Rosso, Dotsenko, and Sasamoto-Spohn imply that the one-point distribution of the solution of the KPZ equation with the narrow wedge initial condition coincides with that for a multiplicative statistics of the Airy determinantal random point process. Taking Taylor coefficients of the two sides yields moment identities. We provide a simple direct proof of those via a combinatorial match of their multivariate integral representations.

Topics: Probability, Mathematical Physics, Mathematics

Source: http://arxiv.org/abs/1608.01557

3
3.0

Jun 29, 2018
06/18

by
Hèla Ayadi

texts

#
eye 3

#
favorite 0

#
comment 0

In the context of an infinite locally finite weighted graph, we give a necessary and sufficientcondition for semi-Fredholmness of the Gauss-Bonnet operator. This result is a discrete version of thetheorem of Gilles Carron in the continuous case [5]. In addition, using a criterion of Anghel [2], we givea sufficient condition to have an operator of Gauss-Bonnet with closed range. Finally, this work can beconsidered as an extension of the work of Colette Ann\'e and Nabila Torki-Hamza [3].

Topics: Spectral Theory, Functional Analysis, Mathematics

Source: http://arxiv.org/abs/1612.03750

3
3.0

Jun 29, 2018
06/18

by
Rita Ferreira; Peter Hästö; Ana Margarida Ribeiro

texts

#
eye 3

#
favorite 0

#
comment 0

The norm in classical Sobolev spaces can be expressed as a difference quotient. This expression can be used to generalize the space to the fractional smoothness case. Because the difference quotient is based on shifting the function, it cannot be used in generalized Orlicz spaces. In its place, we introduce a smoothed difference quotient and show that it can be used to characterize the generalized Orlicz-Sobolev space. Our results are new even in Orlicz spaces and variable exponent spaces.

Topics: Functional Analysis, Mathematics

Source: http://arxiv.org/abs/1612.04566

5
5.0

Jun 29, 2018
06/18

by
Ming Xu; Shaoqiang Deng

texts

#
eye 5

#
favorite 0

#
comment 0

A piecewise flat Finsler metric on a triangulated surface $M$ is a metric whose restriction to any triangle is a flat triangle in some Minkowski space with straight edges. One of the main purposes of this work is to study the properties of geodesics on a piecewise flat Finsler surface, especially when it meets a vertex. Using the edge-crossing equation, we define two classes of piecewise flat Finsler surfaces, namely, Landsberg type and Berwald type. We deduce an explicit condition for a...

Topics: Differential Geometry, Combinatorics, Mathematics

Source: http://arxiv.org/abs/1608.05896

5
5.0

Jun 29, 2018
06/18

by
Jan Kynčl

texts

#
eye 5

#
favorite 0

#
comment 0

An abstract topological graph (briefly an AT-graph) is a pair $A=(G,\mathcal{X})$ where $G=(V,E)$ is a graph and $\mathcal{X}\subseteq {E \choose 2}$ is a set of pairs of its edges. The AT-graph $A$ is simply realizable if $G$ can be drawn in the plane so that each pair of edges from $\mathcal{X}$ crosses exactly once and no other pair crosses. We show that simply realizable complete AT-graphs are characterized by a finite set of forbidden AT-subgraphs, each with at most six vertices. This...

Topics: Combinatorics, Discrete Mathematics, Computing Research Repository, Mathematics

Source: http://arxiv.org/abs/1608.05867

3
3.0

Jun 29, 2018
06/18

by
Xudong Chen; Mohamed-Ali Belabbas; Tamer Basar

texts

#
eye 3

#
favorite 0

#
comment 0

A cluster consensus system is a multi-agent system in which the autonomous agents communicate to form multiple clusters, with each cluster of agents asymptotically converging to the same clustering point. We introduce in this paper a special class of cluster consensus dynamics, termed the $G$-clustering dynamics for $G$ a point group, whereby the autonomous agents can form as many as $|G|$ clusters, and moreover, the associated $|G|$ clustering points exhibit a geometric symmetry induced by the...

Topics: Dynamical Systems, Mathematics

Source: http://arxiv.org/abs/1601.06346

5
5.0

Jun 30, 2018
06/18

by
Ludovic Chandesris; Valentin Savin; David Declercq

texts

#
eye 5

#
favorite 0

#
comment 0

This paper focuses on the recently introduced Successive Cancellation Flip (SCFlip) decoder of polar codes. Our contribution is twofold. First, we propose the use of an optimized metric to determine the flipping positions within the SCFlip decoder, which improves its ability to find the first error that occurred during the initial SC decoding attempt. We also show that the proposed metric allows closely approaching the performance of an ideal SCFlip decoder. Second, we introduce a...

Topics: Information Theory, Computing Research Repository, Mathematics

Source: http://arxiv.org/abs/1701.04736

7
7.0

Jun 30, 2018
06/18

by
Jesús Guillera

texts

#
eye 7

#
favorite 0

#
comment 0

Using a self-replicating method, we generalize with a free parameter some Borwein algorithms for the number $\pi$. This generalization includes values of the Gamma function like $\Gamma(1/3)$, $\Gamma(1/4)$ and of course $\Gamma(1/2)=\sqrt{\pi}$. In addition, we give new rapid algorithms for the perimeter of an ellipse.

Topics: Number Theory, Mathematics

Source: http://arxiv.org/abs/1702.05378

3
3.0

Jun 30, 2018
06/18

by
Eric Bach; Jeremie Dusart; Lisa Hellerstein; Devorah Kletenik

texts

#
eye 3

#
favorite 0

#
comment 0

Recently, Deshpande et al. introduced a new measure of the complexity of a Boolean function. We call this measure the "goal value" of the function. The goal value of $f$ is defined in terms of a monotone, submodular utility function associated with $f$. As shown by Deshpande et al., proving that a Boolean function $f$ has small goal value can lead to a good approximation algorithm for the Stochastic Boolean Function Evaluation problem for $f$. Also, if $f$ has small goal value, it...

Topics: Computing Research Repository, Discrete Mathematics

Source: http://arxiv.org/abs/1702.04067

3
3.0

Jun 29, 2018
06/18

by
Dinh Hoa Nguyen; Tatsuo Narikiyo; Michihiro Kawanishi

texts

#
eye 3

#
favorite 0

#
comment 0

This paper proposes a new approach to analyze and synthesize robust consensus control laws for general linear leaderless multi-agent systems (MASs) subjected to input constraints or uncertainties. First, the MAS under input constraints or uncertainties is reformulated as a network of Lur'e systems. Next, two scenarios of communication topology are considered, namely undirected and directed cyclic structures. In each case, a sufficient condition for consensus and the design of consensus...

Topics: Optimization and Control, Systems and Control, Computing Research Repository, Mathematics

Source: http://arxiv.org/abs/1605.03648

15
15

Jun 29, 2018
06/18

by
Ayse Alaca; Saban Alaca; Zafer Selcuk Aygin

texts

#
eye 15

#
favorite 0

#
comment 0

We express all the newforms of weight $2$ and levels $30$, $33$, $35$, $38$, $40$, $42$, $44$, $45$ as linear combinations of eta quotients and Eisenstein series, and list their corresponding strong Weil curves. Let $p$ denote a prime and $E (\zz_p)$ denote the the group of algebraic points of an elliptic curve $E$ over $\zz_p$. We give a generating function for the order of $E (\zz_p)$ for certain strong Weil curves in terms of eta quotients and Eisenstein series. We then use our generating...

Topics: Number Theory, Mathematics

Source: http://arxiv.org/abs/1604.07774

4
4.0

Jun 29, 2018
06/18

by
Catherine Bandle; Moshe Marcus; Vitaly Moroz

texts

#
eye 4

#
favorite 0

#
comment 0

We study a nonlinear equation in the half-space $\{x_1>0\}$ with a Hardy potential, specifically \[-\Delta u -\frac{\mu}{x_1^2}u+u^p=0\quad\text{in}\quad \mathbb R^n_+,\] where $p>1$ and $-\infty

Topics: Analysis of PDEs, Mathematics

Source: http://arxiv.org/abs/1604.08830

4
4.0

Jun 30, 2018
06/18

by
Konstantinos Tyros

texts

#
eye 4

#
favorite 0

#
comment 0

We provide primitive recursive bounds for the finite version of Gowers' $c_0$ theorem for both the positive and the general case. We also provide multidimensional versions of these results.

Topics: Mathematics, Combinatorics

Source: http://arxiv.org/abs/1401.8073

3
3.0

Jun 30, 2018
06/18

by
Barbara Baumeister; Matthew Dyer; Christian Stump; Patrick Wegener

texts

#
eye 3

#
favorite 0

#
comment 0

In this note, we provide a short and self-contained proof that the braid group on n strands acts transitively on the set of reduced factorizations of a Coxeter element in a Coxeter group of finite rank n into products of reflections. We moreover use the same argument to also show that all factorizations of an element in a parabolic subgroup of W lie as well in this parabolic subgroup.

Topics: Mathematics, Combinatorics, Representation Theory, Group Theory

Source: http://arxiv.org/abs/1402.2500

3
3.0

Jun 29, 2018
06/18

by
Katja Sagerschnig; Travis Willse

texts

#
eye 3

#
favorite 0

#
comment 0

We analyze the classic problem of existence of Einstein metrics in a given conformal structure for the class of conformal structures inducedf Nurowski's construction by (oriented) (2,3,5) distributions. We characterize in two ways such conformal structures that admit an almost Einstein scale: First, they are precisely the oriented conformal structures $\mathbf{c}$ that are induced by at least two distinct oriented (2,3,5) distributions; in this case there is a 1-parameter family of such...

Topics: Differential Geometry, Mathematics

Source: http://arxiv.org/abs/1606.01069

4
4.0

Jun 29, 2018
06/18

by
Laure Flapan

texts

#
eye 4

#
favorite 0

#
comment 0

We consider algebraic surfaces, recently constructed by Schreieder, which are smooth models of the quotient of the self-product of a complex hyperelliptic curve by a $\mathbb{Z}/3^c\mathbb{Z}$-action. We show that these surfaces are elliptic modular surfaces attached to a particular subgroup of index $6\cdot 3^c$ in $SL(2,\mathbb{Z})$. In particular, this implies that Schreieder's surfaces are extremal elliptic surfaces, meaning they have maximal Picard rank and Mordell-Weil rank $0$. In fact,...

Topics: Algebraic Geometry, Mathematics

Source: http://arxiv.org/abs/1603.05613

3
3.0

Jun 30, 2018
06/18

by
Serafina Lapenta; Ioana Leustean

texts

#
eye 3

#
favorite 0

#
comment 0

We prove that any MV-algebra has a faithful state can be embedded in an \em{f}MV-algebra of integrable functions. As consequence, we prove H\"older's inequality and Hausdorff moment problem for MV-algebras with product and we propose a solution for the stochastic independence of probability MV-algebras.

Topics: Mathematics, Logic

Source: http://arxiv.org/abs/1410.5658

3
3.0

Jun 30, 2018
06/18

by
M. T. Yamashita; F. F. Bellotti; T. Frederico; D. V. Fedorov; A. S. Jensen; N. T. Zinner

texts

#
eye 3

#
favorite 0

#
comment 0

The spectrum and properties of quantum bound states is strongly dependent on the dimensionality of space. How this comes about and how one may theoretically and experimentally study the interpolation between different dimensions is a topic of great interest in different fields of physics. In this paper we study weakly bound states of non-relativistic two and three boson systems when passing continuously from a three (3D) to a two-dimensional (2D) regime within a 'squeezed dimension' model. We...

Topics: Quantum Physics, Quantum Gases, Mathematics, Nuclear Theory, Mathematical Physics, Condensed Matter

Source: http://arxiv.org/abs/1404.7002

4
4.0

Jun 30, 2018
06/18

by
Charles-Michel Marle

texts

#
eye 4

#
favorite 0

#
comment 0

Groupoids are mathematical structures able to describe symmetry properties more general than those described by groups. They were introduced (and named) by H. Brandt in 1926. Around 1950, Charles Ehresmann used groupoids with additional structures (topological and differentiable) as essential tools in topology and differential geometry. In recent years, Mickael Karasev, Alan Weinstein and Stanis{\l}aw Zakrzewski independently discovered that symplectic groupoids can be used for the construction...

Topics: Mathematics, Differential Geometry

Source: http://arxiv.org/abs/1402.0059

9
9.0

Jun 30, 2018
06/18

by
Yang-Hui He; Cyril Matti; Chuang Sun

texts

#
eye 9

#
favorite 0

#
comment 0

The so-called Scattering Equations which govern the kinematics of the scattering of massless particles in arbitrary dimensions have recently been cast into a system of homogeneous polynomials. We study these as affine and projective geometries which we call Scattering Varieties by analyzing such properties as Hilbert series, Euler characteristic and singularities. Interestingly, we find structures such as affine Calabi-Yau threefolds as well as singular K3 and Fano varieties.

Topics: High Energy Physics - Theory, Mathematics, Algebraic Geometry

Source: http://arxiv.org/abs/1403.6833