The End (The Beginning)

And we've reached the end of the line - the Black Hole. This is an artistic rendering of what they might look like. It's doubtful anyone will know for sure for a long, long time, since they don't emit radiation of the type that allows us to see, and in fact, suck it in (the whole "Not even light can escape a Black Hole"). Perhaps you've wondered how this could be? I'm glad you asked!


Black Holes are a rather clear example of what I was talking about a few days ago, regarding "things" as opposed to "ongoing processes". There is nothing which actually makes up a Black Hole. Rather, everything we call a "Black Hole" is merely the result of a massive (and I mean massive) gravitational event which effects all of the space-time around it - we call these effects a "Black Hole". Semantic distinction, perhaps, but what isn't semantics?


So, a Black Hole is really an extreme gravitational event. I find myself amazed all the time to know that no one really understands what gravity is. You might think that's the most knowable force in the universe, since we experience it all the time - drop a rock on your toe, there's gravity. Thus, we understand the dynamics of gravity really well - this allows us to fly planes, blast off rockets, etc. However, no one knows what causes gravity, or what it actually is.


There are three main theories of gravity that have gained general currency over the past 300 years: 1. Most well known is Newton's Laws of Gravity. It's quite accurate on a day to day perspective, and in fact we got to the Moon using Newton's theory. Roughly, Newton posited an attractive force that binds matter together - he had no idea what that force is though. However, it's been shown 100% conclusively that it's not entirely accurate - for instance, our GPS system would not work using Newton's theories. Which leads us to, 2. Einstein's Theory of General Relativity. This is essentially the working theory everyone uses now. And while it has been proven in many, very conclusive ways (the GPS system again; the orbit of Mercury was accurately predicted with it; the bending of light by stars was predicted by it), no one seems very confident it's the final answer, since, when it comes to Black Holes (the most extreme gravity), it doesn't work either (it results in an infinite gravitational field within zero space [THE SINGULARITY] - both results are absurd according to current theories). We'll no doubt be sticking with Einstein's theory for a while, because it is very, very accurate. For instance, this theory introduced the concept of Spacetime - a single entity of the spatial dimensions and time. (The 3rd theory is Quantum Gravity, with an actual particle that transmits the gravity force - the graviton. No proof however of this particle, yet).


Gravity in the Einstein perspective is NOT a force. This should be stressed, as it's quite radical. All it is in the geography of space time. To wit: things with mass bend spacetime, and this bending is gravity. Objects with more mass bend it more. We are bending spacetime right now by our very existence, and when move, we create ripples in space time. Objects with the greatest mass bend spacetime to the extreme, as shown here:

As you see, Black Holes appear to rip right through spacetime, and thus our nonsensical, absurd conclusion that it has infinite gravity in zero space. Makes no sense, but this is one of the greatest mysteries in history. I suspect if we ever do find out what's going on in the Singularity, we will have opened the door to an entirely new level of science.


Black Holes vary greatly in size. When big stars explode, they create stellar black holes, and there are no doubt billions of these in the Universe. But black holes can merge with each other, and this merging process was probably quite active in the early universe, when the first stars were being born than quickly dying. They can get so big, in fact, that entire galaxies form around them - it's now believed all major galaxies formed around a "supermassive" black hole.


Black holes also go by different names  - but this is only because until recently, we did not know these different things were the same phenomena. For instance, a supermassive black hole can also be known as a Quasar. Here's a pic:

That's an entire galaxy in the center, with two giant jets of gas shooting out of the poles of the active black hole at the center of this galaxy. Such that quasars = active black holes. They're feeding, in other words.

The black hole in the center of the Milky Way was active a long time ago, but no longer. What happens is after all the chaos of creation, things settle down, and eventually all the matter surrounding the black hole stabilizes in orbits far enough away that it doesn't get sucked in. Once this happens for long enough, the black hole goes quiet, and simply spins in the middle of the galaxy, creating the momentum for the entire galaxy's rotation.

It's even possible there are micro black holes everywhere - right in front of your nose, for example. But little proof has been offered for their existence or creation.

I leave with you the most common type of black hole: the Binary star system, unbalanced. In the upper right is a real picture of what we assume is a black hole.

Bet you didn't know that the vast majority of stars in the universe are in pairs: Binary systems. Our single star is the exception to the rule. Most of these pairs are lopsided, however, with one bigger than the other. The bigger one exhausts its fuel faster, and thus enters the death spiral faster, and if it's big enough, it will create a neutron star or black hole. Which is the kiss of death for it's surviving sibling. I'm sure as it's getting sucked into nothingness, it's thinking "NOT FAIR!"

But what is "fairness" in this vastness?