h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

After watching several seasons of a TV show called Stargate, I'd really like to ask a question about the main feature of the show - the Stargate. (The Stargate is a device that creates a wormhole, connecting two planets together.)

My question is:

a) Is it/will it ever be possible for humans to create a wormhole?

b) Is it possible to travel through a wormhole?

Any and all information would be much appreciated.

Hello Pegasus

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It actually connects two gates, they don't have to be on different planets (there are two on , right?)

To answer your question a) I'd need a crystal ball, which I don't have and b) I have wondered who was the first of the Ancients to test it I recall in early Star Trek they had some problems with the transporter...

It would be a way to travel, wouldn't it?

Yeah, you're right about the two gates being connected. The only problem is, you can't connect two gates that are on the same planet.

I haven't seen early episodes of Star Trek, but I do remember other problems with the transporter.

It would be an amazing way to travel. Maybe one day...

Something to do with negative energy. I have to reread Science of Discworld III.

TRiG.

You know, I read the title of this and knew it would be you asking this pegasus

the idea that you can travel through a wormhole is based on a particular set of mathematical equations (from various theoretical physicists) which, when modelled in 4 dimensions, seem to show that the funnel shape of a blackhole opens out on the 'other side'. The 'otherside' is known as a white hole.

By which I mean the standard visual representation of a black hole as a gravity well, a funnel if you like in the space time continuum, reaches a 1 dimensional point (the singularity) and then opens out again the other side. Imagine a two funnels connected by their smallest point.

In this the show is playing a bit fast and loose, as I understand it, in that a wormhole is actually a theorised singularity without a blackhole around it. Such things would be very dangerous in space since they would be undetectable (as far as we know - how do you detect a one dimensional point?) until you hit it, and then it is too late as you will be compressed into nothingness.

Could humans create such a thing should it be possible?

Well, quite likely, although the energy requirements would be phenomenal. Humans have already created mini black holes in the laboratory (luckily v.v.v.small ones tend to evaporate rather than grow as sci-fi would have us believe).

Could we travel through them?
Am interesting question. Nothing we know of would protect us from the forces as we approach the singularity. Also, I think, the hypothesis (I wouldn't go so far as to call them theories) is that to travel through a wormhole you would have to 'miss' the singularity. Sort of slide down the side wall of the funnel and miss out the singularity itself. This would require some way of countering the forces involved. Since the forces involved prevent even the escape of light, any such travel would require a faster than light travel. This is purely hypothetical. Which is not to say it is impossible, but current theories would argue against it.

OTOH, I think the stargates are more like the idea of space warps, whereby one region of space is directly connected to another. IOt is kinda like teleportation. This is possible and I can't remember the name of the effect. Begins with a 'c' I think. But basically it is possible with enough energy to start with two plates which are connected to each other (ie side by side). You then move the plates apart but they remain connected such that anything enteromg plate A emerges at plate B even though there is distance between them.

As I understand it the requirements to make this work would require more energy than would be released by our sun going nova.

I shall now await the physicist who shall correct my misunderstandings!

Thanks TRiG. I'm borrowing that book from someone at the moment, so I'll have a read too.

Thank you also Ictoan. The explanations were interesting, and I actually understood it! Wow! (I'm not saying that your explanation was hard to understand, just that my grasp of science isn't as good as yours is.) I've not heard of the two plates thing before. Do you have any more info on it, or websites to go to/books to read?

When you are solving real-world problems which involve equations, you often end up with a number of different solutions, only one of which is actual possible.

Wormholes are like this: they are solutions of the Einstein relativity equations which produce a sort of tube connecting one part of the universe to another. Unfortunately, they are not possible solutions in that they require some matter to have negative mass, which as far as we know is impossible. If it were possible to have wormholes, then you could travel through them if they were big enough. But it does not appear that it will ever be possible.

Black holes are a different thing entirely. They are not tubes, and they are not holes. They are point masses, planets of infinite density which suck matter into themselves. There isn't an "other side" to a black hole. When things fall into the sun, they stay there, unless they are ejected in an explosion. When things fall into a black hole, they stay there, full stop.

And while wormholes are an impossible construct which are useful for science fiction stories, black holes are real things which exist in the universe.

OK, so travelling by a wormhole isn't actually a possibility then. What about the two plates thing? Does anyone know if that's possible?

What two plates are those?

What Ictoan was talking about, but slightly different. It's a way of getting negative energy. There are two plates held close together and you find a negative energy state between them. It's called the Casimir effect. (I'm reading Science of the Discworld here, but I don't understand that bit. Please help!)

Gnomon, get what you are saying but the calculations that describe the warping of spacetime around a blackhole, if extended beyond the singularity, do indeed open out the other side. These are what is known as white holes. It's theory only I grant you, and things may well have moved on since I read that.

Casimir Effect - that's what I was thinking of. And I realise it isn't directly related but it is theorised that the casimir effect could be used to create a negative-mass area of space/time. It's all highly theoretical and possibly completely misunderstood by me

Google Casimir Effect and you'll see, although I'd advise you to read the pages from universities/science sites rather than the sci-fi ones

Ictoan, I'd love to see a good explanation of white holes, because they don't fit in with the reading I've done on black holes at all. THis says that there isn't any "beyond" to a black hole.

I've heard of white holes, but I can't remember where I've read about them. I do remember that what I read, and it may be wrong, said that white holes created matter in a different universe.

As I understand it it isn't really a 'beyond' and they are highly theoretical, but the mathematical models do work.

As for where they 'come out' not sure. I doubt it would be another dimension or universe or anything. Would more likely be another point in space time and the singularity would be a pinch between them.

You'll recall from my post that what I was saying was that the idea of travelling through wormholes/blackholes/whatever is based upon this idea.

That doesn;t make it true, and it doesn't mean that white holes exist or that I think they do. Or that the maths models reality.

What it means is that this particular model/hypothesis which may well have been superceeded was the source for the SciFi idea that you can travel through them. I was trying to show where the idea had come from and thereby that the idea of travelling through them is a little bit on the hypothetical side.

"Unfortunately, they are not possible solutions in that they require some matter to have negative mass, which as far as we know is impossible."

Actually even though such matter has never been observed, there is apparently nothing theoretically that says it couldn´t. Kip Thorne did some research into creating such wormholes, and it may well be theoretically possible. Sadly it would seem that creating a wormhole large enough for a human, would require more energy than exists in the entire universe.

Traveller in Time on top
"Impossible is a state of mind (and technology).

would it not be possible for some in a higher dimension just to fold ours a little creating such things as 'worm holes', 'star gates', 'gate to ever'. Arguments as there is not enough energy in our universe are still holding.

The only problem would be to ask such higher dimensional beeing to fold our space in the right direction. It would be easy enough for them to fold the Earth into a nearby star. "

Presumably such beings would also require energy to do such a bending, who knows how much.

It seems to me then, that there are many theories suggesting that wormholes may be a possibility, however at the moment, there is really no chance of humans creating one, much less travel through them. Would that be a reasonably accurate assessment?

Well the exotic matter mentioned earlier has never been observed, and may not exist. It is just that there is nothing in theory that precludes it´s existence. Even then, creating a wormhole wouldn´t just be a matter of getting more advanced technology, if you need all the energy in the universe for it, it will just never happen.