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The mass distributions of dense cores in star-forming regions are measured to have a shape similar to the initial mass function of stars. This has been generally interpreted to mean that the constituent cores will form individual stars or…

Astrophysics · Physics 2009-11-13 Jonathan J. Swift , Jonathan P. Williams

The structure of the crust of a neutron star is completely determined by the experimentally measured nuclear masses up to a density of the order of 10^11 g.cm^{-3}. At higher densities, the composition of the crust still remains uncertain,…

Nuclear Theory · Physics 2008-11-26 Nicolas Chamel

In particle physics, most of the classical models consider that the centre of mass and centre of charge of an elementary particle, are the same point. This presumes some particular relationship between the charge and mass distribution, a…

General Physics · Physics 2015-05-13 Martin Rivas

We answer the question whether, when forming constellations in the night sky, people in astronomical cultures around the world and through time consistently imagined and assigned the same symbolism to the same (type of) star group. Evidence…

Physics and Society · Physics 2024-04-22 Doina Bucur

A normalized univalent function is uniformly convex if it maps every circular arc contained in the open unit disk with center in it into a convex curve. This article surveys recent results on the class of uniformly convex functions and on…

Complex Variables · Mathematics 2011-08-23 R. M. Ali , V. Ravichandran

The center of our galaxy is home to a massive black hole, SgrA*, and a nuclear star cluster containing stellar populations of various ages. While the late type stars may be too old to have retained memory of their initial orbital…

Astrophysics of Galaxies · Physics 2015-06-18 Ann-Marie Madigan , Oliver Pfuhl , Yuri Levin , Stefan Gillessen , Reinhard Genzel , Hagai B. Perets

Denoting by $\mathbb{M}$ the complexification of the quaternionic algebra $\mathbb{H}$, we characterize the family of those $\mathbb{M}$-valued functions, defined on subsets of $\H$, whose values are actually quaternions, using an intrinsic…

Functional Analysis · Mathematics 2019-05-31 Florian-Horia Vasilescu

In this article we propose a generalization of the 2-dimensional notions of convexity resp. being star-shaped to symplectic vector spaces. We call such curves symplectically convex resp. symplectically star-shaped. After presenting some…

Symplectic Geometry · Mathematics 2022-12-29 Peter Albers , Serge Tabachnikov

We present the interior solution for a static, spherically symmetric perfect fluid star backreacted by QFT in four dimensions invoking no arbitrary parameters. It corresponds to a constant energy density star and is fully non-perturbative.…

General Relativity and Quantum Cosmology · Physics 2025-01-20 Pietro Paolo Melella , Ignacio A. Reyes

Last years studies have shown that the spatial regularity in the distribution of young stellar population along the spiral arms and rings of galaxies, previously considered to be rare, is a fairly common phenomenon. Spatial regularity has…

Astrophysics of Galaxies · Physics 2024-12-31 A. S. Gusev , E. V. Shimanovskaya

We establish the existence of $N$-point sets in dimension $d$ whose star-discrepancy is bounded above by $2.4631832 \sqrt{\frac{d}{N}}$, where the numerical constant improves upon all previously known bounds. This improvement is obtained by…

Number Theory · Mathematics 2026-01-08 Christian Weiß

A point P on a smooth hypersurface X of degree d in an N-dimensional projective space is called a star point if and only if the intersection of X with the embedded tangent space T_P(X) is a cone with vertex P. This notion is a…

Algebraic Geometry · Mathematics 2009-03-12 Filip Cools , Marc Coppens

A theorem of Meyer and Reisner characterizes ellipsoids by the collinearity of centroids of parallel sections: if $\Omega\subset\mathbb{R}^{n+1}$ is a convex body such that for every $n$-dimensional subspace $M\subset\mathbb{R}^{n+1}$ the…

Differential Geometry · Mathematics 2026-01-13 Alexandre Borentain

Quartic gravity theory is considered with the Einstein-Hilbert Lagrangean $R+aR^{2}+bR_{\mu \nu}R^{\mu \nu},$ $R_{\mu \nu}$ being Ricci\'s tensor and R the curvature scalar. The parameters $a$ and $b$ are taken of order 1 km$^{2}.$…

General Relativity and Quantum Cosmology · Physics 2021-06-16 Emilio Santos

The late-type stellar population in the Galactic Center was first predicted to reside in a dynamically relaxed cusp (power law slope ranging from 3/2 to 7/4). However, observations - which rely on models to correct for projection effects -…

Based on the properties of uniform nuclear matter at the nuclear saturation density and basic thermodynamic relations, we first re-study the composition of matter on the surface of normal neutron stars and hybrid stars. It is found that the…

Nuclear Theory · Physics 2021-06-02 Li-Qun Su , Yan Yan , Cheng-Ming Li , Yong-Feng Huang , Hongshi Zong

In this note, we provide a starlike and normal tiling in any separable Banach space. That means, there are positive constants r and R (not depending on the separable Banach space) such that every tile of this tiling is starlike, contains a…

Functional Analysis · Mathematics 2020-08-25 Robert Deville , Mar Jimenez-Sevilla

We show observations obtained with the integral field spectrometer OASIS for the central regions of a sample of barred galaxies. The high spatial resolution of the instrument allows to distinguish various structures within these regions as…

Astrophysics · Physics 2009-11-13 Mercedes Mollá , Simon Cantin , Carmelle Robert , Anne Pellerin

Suppose that to every non-degenerate simplex Delta in n-dimensional Euclidean space a `center' C(Delta) is assigned so that the following assumptions hold: (i) The map that assigns C(Delta) to Delta commutes with similarities and is…

Metric Geometry · Mathematics 2014-10-21 S. Tabachnikov , E. Tsukerman

This is a complete classification of the complex forms of quaternionic symmetric spaces

Differential Geometry · Mathematics 2007-05-23 Joseph A. Wolf