The Universe Is Still Expanding: What Does It Mean?

What Does It Mean

Actually far more complex than you might realize. Which is why many people in NASA and other space programs are fascinated by them. If you’re looking for a technical definition, this is how NASA describes Black Holes: “A black hole is a place in space where gravity pulls so much that even light cannot get out. The gravity is so strong because matter has been squeezed into a tiny space. This can happen when a star is dying.” This singularity as it is often called is a bit of a mystery in space, and for a very good reason. You see, black holes can form in large sizes, small sizes, and sometimes they  don’t even need a fully fledged star to form at all! Which is scary in the sense that it means black holes can form in various ways. Plus, since no light can actually escape them, it means that they can’t technically be seen by anyone.

That being said, it’s easy to “see their work”, as the intense gravity of the Black Holes is enough to stretch objects from their “starting point” and slowly pull them to the Black Hole.  This is known as spaghettification, because like a stretched piece of spaghetti, the object will get thinner and thinner until nothings exists but particles. And if you think that a Black Hole is limited in what it can absorb, you would be wrong. Very wrong in fact. If it is close enough, it’ll break down a star, a planet, multiple stars and planets at once, etc. It’s a question of range more than anything. But there’s a catch to that, as you won’t be able to observe the spaghettification yourself.

Why?

Remember, no light escapes the void that is the Black Hole, so because of that, you’ll see the last known position of the object that light allows you to see. It’ll seem like they’re stuck in place and slowly going away until they’re gone. When in fact, they or it will be slowly pulled apart. As we noted earlier, one of the main ways for a Black Hole to be born is to have a star collapse upon itself with such pressure that a Black Hole is a result. However, technically speaking, just about anything in the universe can become a Black Hole.

How’s that for a scary thought?

It’s true though, and that’s one of the big “scaling” factors that you need to take into account when you’re talking about Black Holes. In fact, there’s actually a scarier thought that you need to consider, and that’s that black holes could technically be all around you right now. The only reason you’re not feeling their affects is that they’re not large enough to exert their own gravity.

The scale of a Black Hole is referred to as the Schwarzschild Radius. And becoming a Black Hole is impendent on you becoming so small and so dense that you can fit into this radius, and then potentially expand upon it. For example, a human being can become a Black Hole if condensed enough. However, the pressure needed to do that would not only be enormous, you could have to be shrunk 1 sextillion times smaller than a grain of sand.

That’s REALLY small.

But that raises the question that we posed earlier, mainly, where do black holes lead to? I mean, if they can be of all sizes, and be anywhere from the size of a massive galaxy to the spec of sand on a beach, how can they lead to anywhere? How does that work? Would it work at all? In the words of one scientist, “Who knows?” “Falling through an event horizon is literally passing beyond the veil — once someone falls past it, nobody could ever send a message back,” he said. “They’d be ripped to pieces by the enormous gravity, so I doubt anyone falling through would get anywhere.” Allow me to back up a little bit. Remember the whole “spagheticfication” thing I was talking about earlier? Well, the place that you would be “stretched to” is the horizon line of the black hole.

Think of a black hole like a funnel.

The big end of the funnel is the black hole that you “see” in space, and the rest of it is the core of the black hole that is hidden beneath its intense gravity. Now, if black holes DID lead somewhere, then like the funnel, you would have an access point through the core that you could go to. You get it? The problem here is that most scientists believe based on their understanding of black holes that a horizon line is what awaits you at the end. So if you think about the funnel again, think about pinching the back end of it so that nothing could get out of said funnel.

That’s what a lot of people think is in the center of a black hole, a literal end point. Which would be a problem for those who think it would lead anywhere…because it wouldn’t. It would end, and as the scientist above noted, you wouldn’t exactly be in one place to see it. IF this is the truth, then the answer to the question of “where do black holes lead to” is quite literally…nowhere. And again, you’d be quite dead before you would ever “find out”. But…if we were to extrapolate another answer that you might appreciate…the OTHER answer Theory to “where do black holes lead to” might just be…”somewhere else”.

And I’m not saying that just to be cute, but rather, to set up the explanation of ANOTHER important theory, the theory…of a wormhole. So if you’ve watched any kind of sci-fi show that dealt with space travel and such, you more than likely have heard of the concept of wormholes. To put it in the most basic of terms, wormholes are “shortcuts” in the universe. You go in through one side of the universe, and you come out in an area that is REALLY far away from where you were just a few minutes ago. Star Trek Deep Space Nine based an entire series on a space station that protected a wormhole that led to another quadrant of space. But are these things really possible in our own universe? And if they were, wouldn’t we have found one yet? The answers may surprise you, especially when you hear that wormholes were speculated upon by one of the most brilliant minds in the world…Albert Einstein. I talked about in this post.

In 1935, Einstein and Nathan Rosen illustrated the idea through the theory of general relativity, proposing bridges across space-time, connecting two different points of space-time, and theoretically creating a shortcut that could reduce travel distance and time. Einstein-Rosen ”or“ wormholes ”. Einstein’s theory of scientific relativity mathematically predicted the existence of wormholes, but no wormholes have been discovered so far. Some equations suggest the existence of wormholes with mouths that are black holes, but obviously we can’t prove whether a black hole is a wormhole because things and objects and people that go into black holes don’t come back out. But we’ll get back to that in a sec.

What this really boils down to though is the concept of space-time, which Albert Einstein theorized was the forces of space and time together in a “fabric” if you were that made up the entire universe. And the reason the Earth, sun, and galaxies are able to do certain things in the universe (like cause orbits of moons and planets and stars) isn’t because of gravity per se, but rather, because they are able to manipulate the space-time around them into “valleys” that cause things to rotate around them because they get trapped into that valley. Due to this, Einstein speculated that space-time could be stretched, warped, depressed, and yes, even torn into. Which is where the original notion of the wormhole came from. Because if you open a “hole” in space-time…there has to be something else on the other side, right?

Wormhole

Believe it or not, Einstein and others have noted that there are potentially 5 different kinds of wormholes. And yeah, some of those theories basically state that a black hole is a kind of wormhole, just one that isn’t really “ready for travel”. But IF the black holes were wormholes also, that could open up all new possibilities for us as a people, you know, if we could actually get to them and use them properly of course. So if they are wormholes and not just black holes, when were they made? The most probable answer is the Big Bang, which is the theoretical event that scientists speculate was the birth of our universe. A moment in which an explosion of mass shot in all directions and created the building blocks of the universe via gasses, matter, and more. It took millions and billions of years to form what we have now according to the theory. But, that leaves a lot of times for certain “holes” in the universe to be formed. In fact, some speculate that because of the violent nature of the Big Bag that there are actually a plethora of wormholes in the universe right now, all connected to another wormhole via “cosmic strings” and they are just waiting to be found. Plus, you need to consider this from the cosmic scope of things. Let’s say that in the universe, the whole universe…there are 5 wormholes. Ones that have a way in and a way out. If you were to randomly place those wormholes in the universe, what is the likelihood of them landing by us? Or in a place that we can view?

Could we even see them in the darkness of space?

We know that black holes can’t be seen, so if all wormholes are black holes, that would be a big fat “no” on that scale. Let’s get back to the topic at hand, let’s say that black holes ARE wormholes, and let’s say that not unlike Star Trek they connect one part of the galaxy to the other, how exactly would that work? The answer here is “cosmic strings”. Basically, when the universe was born via the Big Bang, and the wormholes were made, a “connective tissue” if you will made these wormholes work in the sense of going in one place and going out the other. I know that idea of “cosmic strings” may sound rather sci-fi, but there is some basis for this.

There are also other “theories” as to how the black hole/wormhole thing could work. For example, there are those who speculate that the black hole leads to what is known as a “white hole”. Which is exactly what it sounds like, a polar opposite of a black hole, an entity that spews out matter into the universe instead of sucking it in. In theory, this would make sense, as the black hole would suck in mass from various objects in its way, and then the white hole would “spew” them out in its own way/direction. Plus, a white hole is believed to not be able to “take in” mass, so that would add into the “opposite” factor.

But there’s the twist, a white hole, in theory, wouldn’t be in our “own universe”. Which means that a black hole MAY lead to an entirely NEW universe where the white hole resides. Which of course would mean that the VERY thin line that separates a white hole from a black hole would be the “divider” between dimensions. An interesting thing to think about, but again, kind of impossible to prove at the moment given the very nature of black holes. And of course, beyond the more “standard” theories are the more “out there” ones… “I think the standard story is that they lead to the end of time,” said Douglas Finkbeiner, professor of astronomy and physics at Harvard University. “An observer far away will not see their astronaut friend fall into the black hole. They’ll just get redder and fainter as they approach the event horizon (as a result of gravitational red shift). But the friend falls right in, to a place beyond ‘forever.’ Whatever that means.”

Conclusions

So yeah, that’s totally not a depressing way of thinking of things… But getting back to reality for a bit, what is the answer to “where does a black hole lead to?” In all honesty, all theories and speculation aside, we just don’t know. There is no current way to see or understand what’s at the core of a black hole. It’s possible that it does lead to nothing. It’s possible that it leads to another part of the universe, or another universe entirely. Or it could be that it leads to something that we just don’t understand in any stretch of the imagination that we have right now. We just don’t know.

Here’s the thing though, it’s ok NOT to know just yet. It’s ok to wonder and speculate, because that’s how we start to figure things out. We work at looking for solutions to questions like these, and the result is usually we find the answer somewhere in the middle. Now yeah, given the nature of black holes and how it destroys everything it touches, it may be a while before we solve this mystery. But that just means it’ll be all the more worthwhile once we do solve it.