Black Holes Articles

There are two main ways black holes form: direct collapse or a dying star. Just after the moment of creation, energy was spread more or less uniformly through space, but some places were slightly denser than other. As things got jostled around, some of these areas got so dense that they collapsed into a primordial black hole. It’s thought that these probably were the anchors that created the galaxies. When a really really big star starts to finish it’s fuel and sputter out, it’s internal heat can’t keep gravity at bay anymore and as the star collapses in on itself, the core gets so dense it forms a black hole.

Tag Archive for: black holes

gravity collapse

The Oppenheimer-Snyder Model of Gravitational Collapse: An Overview

Part 1: OverviewPart 2: Mathematical DetailsPart 3: ImplicationsMost people who have spent any time at all studying GR are familiar with the…
Kerr Spacetime

Geodesic Congruences in FRW, Schwarzschild and Kerr Spacetimes

Introduction The theory of geodesic congruences is extensively covered in many textbooks (see References); what follows in the introduction is a brief…
Gaia search for black holes

Gaia and the Race to Detect More Gravitational Waves

Gravitational waves (GW’s) are disturbances in spacetime produced by any massive object moving asymmetrically. However, only the most massive and most…
black holes are not empty

Black Holes Are Not Empty Voids. A Black Hole at the Heart!

Key PointsBlack Holes (BH’s) have a gravitational pull so strong that nothing, not even light, can escape it BH’s can be divided into two…
what are the black hole thermodynamics

What Are the Thermodynamics of Black Holes? A 5 Minute Introduction

Definition/Summary The four laws of black hole thermodynamics are as follows...The Zeroth Law Surface gravity [itex](\kappa)[/itex] is constant…
killing Fields and Black Holes

Exploring the Math in Killing Fields and Black Holes

Killing Vector Field The Killing vector field is a vector field on a differentiable manifold that preserves the metric over spacetime (from this I assume,…
Falling in Black Holes

Black Holes and the Properties of In-Falling Radial Plungers

From 'Exploring Black Holes' by John Wheeler and Edwin Taylor; can apply to any object falling radially towards a static spherical mass (where the mass…

The Schwarzschild Geometry: Physically Reasonable?

 In the last article, we looked at various counterintuitive features of the Schwarzschild spacetime geometry, as illustrated in the Kruskal-Szekeres…

The Schwarzschild Geometry: Spacetime Diagrams

 When we left off in part 2, we were looking at the metric for the Schwarzschild geometry in Kruskal-Szekeres coordinates:$$ ds^2 = \frac{32…

The Schwarzschild Geometry: Coordinates

 At the end of part 1, we looked at the form the metric of the Schwarzschild geometry takes in Gullstrand-Painleve coordinates:$$ ds^2…

The Schwarzschild Geometry: Key Properties

 Not long after Einstein published his Field Equation, the first exact solution was found by Karl Schwarzschild. This solution is one of the…

Do Black Holes Really Exist?

The purpose of this article is to discuss the title question from several different viewpoints, in order to show that it isn't as simple as it looks. We…

Is the Universe a Black Hole?

In the early universe, the matter was gathered together at very high density, so why wasn't it a black hole?The first thing to understand is that the…

Learn Time Dilation and Redshift for a Static Black Hole

The following is an overview of the time dilation and gravitational redshift effects of a static (Schwarzschild) black hole. In accordance with general…

Will All Matter Be Converted to Photons?

FAQ: In the very distant future, will all matter be converted into black holes and then photons? No. There is a misconception that a lot of laypeople…

An Equation for the Centrifugal Force Reversal Near A Black Hole

My goal in this article is to derive a simple equation for the proper acceleration of an observer traveling on a circular path around a Schwarzschild black…

What are the Fates of Massive Stars

Key PointsStars are born in primordial nebulae, gaseous molecular clouds on the spiral arms of galaxies Stars smaller than 1.4 suns will settle…