Holey Space

Nope that’s not a typo and this isn’t technically about religion or another reconversion post. 🙂  This post is about holes in space, namely black holes, wormholes, and the lesser known white holes, and their implications to the physical and metaphysical. The arrangement or flow of exposition of this article, from black to worm to white hole, will become much clearer as you read along the article. So get ready for a layman’s quick rundown on holes (cosmic ones of course), thought experiments, sci-fi love, paradoxes, and various possible implications in our lives and the universe we live in.

Black holes

The scientific definition for  black hole, specifically in general relativity, that I prefer is that it is a region in space whose escape velocity within its event horizon exceeds the speed of light, and at its core is a singularity. What this means in more layman’s terms is that a black hole’s gravitational pull is so massive, which gives the more well known fact that not even light can escape it.  The reason is that, for an object to escape or “pull out” from a celestial body, whether this be a planet or moon or sun or in this case a black hole, the object must exceed the body’s escape velocity. On Earth, rockets launched into space must have an escape velocity that exceeds 11.2 Km/s, which is the Earth’s escape velocity. For black holes, the escape velocity is greater than 300,000,000 m/s (speed of light). Since we know of nothing that can exceed the speed of light, light and everything else therefore can’t escape the black hole.

You can actually think of a black hole as having sections, very much like a planet’s interior or even an avocado. The event horizon of a black hole is a sphere surrounding the black hole, and is the point of no return. Once you fall into the event horizon, there’s no going back.

The next section is the singularity. Singularity is a fancy term in physics and mathematics which means infinite density or infinite curvature. Density as you recall is mass divided by volume. When an object, which has mass, is compressed to zero i.e. a point with no dimension or volume, then you get a singularity. You could think of a black hole as “pinch” in the fabric of space-time which I discussed in an earlier post of mine. You can also think of it as a vortex, similar to a whirlpool when you stir water in a glass of water and you create a funnel-like shape. In this case, it’s a vortex in the space-time continuum, which could possibly lead to alternate universes.

One of the more curious and famous implications of black holes, and further down the road for the other cosmic holes, is time travel. 

Physical/Metaphysical implications:

The famous physicist Stephen Hawking jokingly conjectured, “If time travel is possible, then where are the tourists from the future?”. Of course a lot of silly and smart alec answers can be given, but if you really think about it, it’s a genuinely profound question. If time travel was indeed possible, what of history? People could go back in time rewriting history as they see fit, or just altering some events in their lives whether trivial or not, and which could have disastrous consequences in the future.

In fact, if time travel is possible and there are/were time travelers among us, we could be living in an alternate universe where the 9/11 attack happened, and that the Dalai Lama was never killed. One alternate universe then had any of the combinations happen: 9/11 happened and the Dalai Lama was killed, 9/11 didn’t happen and the Dalai Lama wasn’t killed and so on. These possibilities are under the many worlds interpretation, where there are countless universes, where every conceivable or even inconceivable outcomes occur.

The movie series Back to the Future does not use the many worlds interpretation however, since in this case if you change something in the past, you “erase” whatever that change could have been in the future. In other words, if you kill somebody in the past, then in the future, everyone who ever knew that somebody will immediately forget about him/her. Everybody related to that somebody, including events, will also be removed/erased out of existence and history, just like erasing your sketch on a piece of paper. This type of interpretation of the universe, although good for entertainment and sci-fi, has more paradoxes and questions left unanswered, that’s why I am more inclined to take on the side of the many worlds interpretation.

Another paradox of time travel is that you can be your own child, father, and mother.

Consider a brilliant man who who was raised as an orphan and invents things for a living. He eventually meets a mysterious woman and marries her, copulates with her, and they conceive a child. Sometime later the woman then mysteriously disappears along with your child. Distraught with grief, the man pours all his time and effort to building a time machine. Unfortunately, successfully building a time machine wasn’t enough to fill the emotional void for the man, and so he decides to have an operation and have his sex changed.  Furthermore, she (previously a he) decides to go back in time as an escape to it all. She then travels back in time, meets a brilliant young man, bears him a child, and then decides it was wrong to do so. So she takes the child with her into the time machine and leaves the child at a much earlier time in an orphanage.

These types of paradoxes can quite certainly make your head spin, while trying to unravel the tangle in the family tree. The man/woman/child was an entire family all by her/himself!

Wormholes

Worm holes, although recently coined in 1957 by theoretical physicist John Wheeler, and theorized as early as 1921 by mathematician Hermann Weyl, have been part of popular fiction since the 19th century. By this I mean the wormhole in the famous (and one of my favorite books) children’s book Through the Looking-glass, and What Alice Found There by Carol Dodgson or more commonly known as Lewis Caroll. The looking-glass in this case is reminiscent of a wormhole, i.e. a pathway to another universe.

Much of what is written here relates to transversible wormholes, or wormholes that won’t destroy you or your starship as you travel through the hole, unlike other proposed wormholes which aren’t transversible by starship. Much of the transversible wormhole information started from famous physicist Kip Thorne and his colleagues.

The illustration above is a 2D analog of a 3D wormhole. In reality, a 3D wormhole is really on a 4D space-time. But usually 2D analogs make the concept much easier to visualize and grasp. In this illustration the shortest distance from one point in space to another is not a straight line, but instead, a wormhole. This is clearly seen when you have 2 points on a piece of paper. Naturally you’d think a straight line is indeed the shortest path between the points. However, if you fold the paper such that the 2 points are directly opposite of each other, then a direct path/link from one point to the other via this curved/folded arrangement is most certainly shorter than a straight line on the piece of paper. This is similar to the case of a wormhole. In the image above,  a light ray is represented by a single line.

Physical/Metaphysical implications:

One cool, currently hypothetical implication of wormholes is multiply connected space. Let’s do one thought experiment again shall we?

Imagine you’re in a museum staring at a painting by Picasso. Now you were suddenly startled by something appearing in front of you, so you momentarily move your attention away from the Picasso artwork. You find that there’s a mirror on the space in front of you. Or rather, a hole floating in the space just in front of you.

When you peer into the hole, you see your father when he was just 17! He then stares at you, not knowing you will become the future fruit of his loins. You become more curious (I know I would!) and decide to go around/behind the hole, to find out what you will then see there. Amazingly you don’t see your father or your father’s back, but instead you see your mother when she was 17! Again, she looks at you perplexed, thinking how oddly dressed you are.

You then realize that this is the prom night of your mother and father back in high school, in a different time and place. From your mother and father’s “universe” however, they were also startled to find a mirror or hole between them while they were dancing. When your father, 17 yeas of age, peers through the hole, he sees a strangely dressed young person looking surprised (you). From your mother’s POV she sees the Picasso painting. But since you decided to move around the hole to observe further, your father saw you leave the mirror. Your mother on the other hand sees a young person block the view of the Picasso painting.

But being the curious fellow that you are, you decided to look at the hole sideways, only to be surprised at the fact that you can’t see anything from a sideways POV, nothing even remotely as thin as paper. Is that cool or what?

Here’s another cool trick you can do at this point: Suppose you wanted to shake hands with your father, so you stick your arm into the hole (never minding the large gravitational forces or radiation that will crush your arm if this was a non-transversible wormhole). Your father reaches out a hand and shakes yours. However you notice that you can also stick your other arm into the other side of the hole, and so you do. You find out that you’re now shaking hands with your mother. Out of this world right?

White holes

White holes are reversed black holes, in that they spew out matter/material. As you may have already figured out, the complete picture of a “tunnel” through space-time ends with a white hole. That is, it usually starts with a black hole, which then creates a wormhole, and then exits via a white hole.

Physical/Metaphysical implications:

Recently some scientists, based on their research, proposes that white holes are actually starters of “Big bangs”, i.e. they create universes, and that the number of universes created by our own universe is directly proportional to the number of black holes in it. This is because, if the theory is proven correct, on the other side of a black hole is a white hole, wherein perhaps all the matter that fell into the black hole would come out in an immense fashion out through a white hole.

This could then mean that the theistic, common Judeo-Christian interpretation of God therefore didn’t create our universe, since at the very least there was a minimum of one universe from which our universe owes its existence to.

Resources, references, and further reading

• Wikipedia article on black holes
• Wikipedia article on wormholes
• Wikipedia article on white holes
• Wikipedia article on the many-worlds interpretation
• Through the Looking-Glass, and What Alice Found There, in different ebook and mobile formats, free for download.

• Hyperspace-A Scientific Odyssey Through Parallel Universes, Time Warps, and the Tenth Dimension, Michio Kaku, ISBN-0-385-47705-8

Originally published at http://f241vc15.wordpress.com/2009/11/08/holey-space/