www.egwald.com Egwald Web Services

Egwald Web Services
Domain Names
Web Site Design

Egwald Website Search JOIN US AS A FACEBOOK FAN Twitter - Follow Elmer WiensRadio Podcasts - Geraldos Hour


Statistics Programs - Econometrics and Probability Economics - Microeconomics & Macroeconomics Operations Research - Linear Programming and Game Theory Egwald's Mathematics Egwald's Optimal Control
Egwald Home Mathematics Home Astronomy Space Curvature Globular Cluster Gravitational Lensing Stellar Collapse References & Links

Egwald: Topics in Astronomy and Cosmology


Elmer G. Wiens ***

Egwald's popular web pages are provided without cost to users.
Please show your support by joining Egwald Web Services as a Facebook Fan: JOIN US AS A FACEBOOK FAN
Follow Elmer Wiens on Twitter: Twitter - Follow Elmer Wiens

Topics in Astronomy and Cosmology

Astronomy is the Universe taking a selfie.

Cold Play - A Sky Full of Stars (Live Buenos Aires’ River Plate Stadium)

The following astronomy web pages present some topics in Astronomy.

1. Curvature of Space: The cosmological principle states that the Universe is homogeneous and isotropic on large scales. Three cosmological models of the spatial constituent of the Universe that conform to this principle are hypersurfaces in a 4-dimensional space with uniform positive, zero, and negative curvature. The space of each model is specified by systems of coordinates that locate an object, and by a metric that determines the distance between objects

2. Globular Clusters: Globular clusters consist of tens, to hundreds of thousands of mainly low mass, old low-metal stars bound together by their mutual gravitational attraction in a dense, slowly rotating sphere that orbits the center of a galaxy. The stars in these clusters formed when the Universe was still young, from huge clouds of abundant hydrogen and helium gas that collapsed under each cloud's internal gravity.

3. Gravitational Lensing: Gravitational lensing refers to the perceived influence of a celestial object's gravity on light passing by the object. The object's mass bends spacetime, bending light's path, and focusing its measured brightnes. As predicted by Einstein's Theory of General Relativity, the foreground object acting as a lens may generate multiple images or ring-images of the background object's emitted light.

4. Stellar Collapse: Stars that stop generating energy through nuclear fusion die. Smaller stars transform into white dwarf stars. Larger stars collapse to form neutron stars or black holes. Much larger stars may blow apart. Various coordinate transformations of the Schwarzschild metric are used to calculate geodesic trajectories of particles and radiation at various radii about stellar objects collapsing from self-gravitation. Within a black hole, the mechanics of stellar collapse are modelled with the geodesics of the Robertson-Walker metric (FLRW).

5.Links and References



      Copyright © Elmer G. Wiens:   Egwald Web Services       All Rights Reserved.    Inquiries