• This forum is specifically for the discussion of factual science and technology. When the topic moves to speculation, then it needs to also move to the parent forum, Science Fiction and Fantasy (SF/F).

    If the topic of a discussion becomes political, even remotely so, then it immediately does no longer belong here. Failure to comply with these simple and reasonable guidelines will result in one of the following.
    1. the thread will be moved to the appropriate forum
    2. the thread will be closed to further posts.
    3. the thread will remain, but the posts that deviate from the topic will be relocated or deleted.
    Thank you for understanding.​

Black Hole, WormHole, or Other?

Meatball

Registered
Joined
Jun 13, 2010
Messages
7
Reaction score
0
Location
North Carolina
Hey all,

I'm trying to come up with a plausible way that ships can jump from one location in the universe to another using 'natural' phenomena. My first thoughts were of course to black holes and wormholes.

As for black holes, I just don't see how someone can physically traverse a black hole without being smashed to bits. Wormholes on the other hand are hypothetical and seem somewhat of a cop-out since everyone uses them.

What do you all think? Could/should I use either of those as my 'jump' mechanisms, or is there another phenomena out there I could possibly use?

Thanks!
 

TMA-1

Super Member
Registered
Joined
May 21, 2005
Messages
166
Reaction score
7
Age
46
Location
Sweden
Wormholes are theoretically possible, but it's probably tricky to keep them open and stable enough for a ship to go through. Various ideas have been proposed. Travelling through a wormhole would get you from point A to point B faster than a beam of light would in normal space, but it doesn't count as FTL anyway. So the wormhole is an interesting idea.

A black hole wouldn't work as far as I know, it's a singularity with all the mass concentrated in it, and if you get too close (below the event horizon) there is no way to escape, even for light.
 

benbradley

It's a doggy dog world
Super Member
Registered
Joined
Dec 5, 2006
Messages
20,322
Reaction score
3,513
Location
Transcending Canines
I agree about wormholes being a copout, I find the wormhole idea so tenuous that I don't think I'd use it as something plausible in a "real" SF work.

I suppose you have to decide on the intended audience (I'm presuming you're writing fiction in which some form of FTL travel is needed) and how important "subspace" travel is in your story. You don't necessarily have to use the word wormhole, you can say "traveling through subspace/hyperspace/jumpspace" or whatever, and it's an acceptable trope for most SF audiences - it's been in use for many decades.

Here's Wikipedia's article on wormholes, and it doesn't sound a bit like use of wormholes in the Saturday Morning Cartoons (that Isaac Asimov wrote about and railed against decades ago in one of his IASFM editorials):
http://en.wikipedia.org/wiki/Wormhole

There looks to be a whole lot of basic science and technology involved in making a "transversable wormhole" (such as "exotic matter" with negative mass) and I imagine this would be hundreds of years in the future at best.

There's really no way to do this and IMHO be true to science, but that doesn't mean you can't do it in a story.
 

Lhun

New kid, be gentle!
Super Member
Registered
Joined
Jan 30, 2007
Messages
1,956
Reaction score
137
Hard science fiction has no way of believably having FTL travel, since we can quite easily observe causality and relativity, and that's incompatible with FTL.
While wormholes are theoretically possible (providing one figures out how to generate negative energy) they require an impossible amount of energy (impossible, not impractical). Even given some kind of future advancement of science and technology that found some other way of achieving FTL, that would consequently mean relativity or causality go out the window. Most likely causality (it's much less proven than relativity), a result that makes things ... complicated.

You an however still write perfectly hardish SF by just glossing over that an using some kind of magical FTL drive. I'd personally recommend using any kind of discontinuous drive, it's more believable that way to simply ignore the causality problems. For believability, what kind of description you write and what rules you set for the drive doesn't matter half as much as staying consistent with the rules from then on, and seriously thinking through the implications of a drive like that being available.

If you're writing space opera, don't sweat the small stuff. Make it generally consistent, and avoid midichlorians, and it'll be perfectly fine. David Weber is an extremely successful example of using technobabble to gloss over the lacking realism of his FTL drive. (and the STL drive!) Heck, he writes military space opera and the weapon technology and battles he describes are totally ridiculous given the FTL and STL technology those ships supposedly have. And people don't care too much. Though he likely doesn't sell to the same kind of readers that read hard SF of course. The genre you aim for defines the minimum of realism and consistency. Though of course, more realism and consistency never hurt, if you write an exiting space opera with big drama and big battles AND a high degree of realism you have an even bigger target audience.

Addedum: Please don't use black holes though. It's just a name, they're not holes, and travelling through them is very fantasy-ish. Using a small one to power a drive or generate gravity or some other purpose is fin(-ish) but no reappearing on the "other side of a black hole" please. That's almost worse than that episode of ST:Voyager where they describe the event horizon as an energy field ... and proceed to blast a hole in it.
 
Last edited:

small axe

memento mori
Super Member
Registered
Joined
Apr 6, 2007
Messages
1,940
Reaction score
261
you can say "traveling through subspace/hyperspace/jumpspace" or whatever, and it's an acceptable trope for most SF audiences - it's been in use for many decades.

It might tie into the OP's question, so I'll ask too: Given that those terms are common tropes ... are there any commonly accepted definitions or differences between them? :)

I mean, is there some point at which your readers will rebel and cry "excuse me, buddy, but you just blew your credability because that ain't "hyperspace" your ship's moving through, it's "subspace" etc?

From the list, I'd assume that via "jumpspace" you're Here and then you're There without traveling anything inbetween; but are there established genre "trope" rules about how hyperspace works versus subspace etc?

Or are they mostly just terms of fiction and necessity which each author can freely use or explain according to their own needs (that is, we don't want to violate REAL physics, but is it likely we'll violate imaginary physics too?)

If possible, can anyone point us to a website etc that explains such issues?
 
Last edited:

Lhun

New kid, be gentle!
Super Member
Registered
Joined
Jan 30, 2007
Messages
1,956
Reaction score
137
It might tie into the OP's question, so I'll ask too: Given that those terms are common tropes ... are there any commonly accepted definitions or differences between them? :)
There are some, but they're fairly obvious.
From the list, I'd assume that via "jumpspace" you're Here and then you're There without traveling anything inbetween; but are there established genre "trope" rules about how hyperspace works versus subspace etc?
No. While use of the term "jump" most of the time refers to some kind of discontinuous drive, hyperspace and subspace get used any way. Often to refer to some kind of alternate space drive, but the warp drive in StarTrek for exampe (which uses subspace) is described as a realspace drive. And even "jump" gets used by some authors to refer to the change into hyper/subspace.
So, the only rule really is: don't name your drive something that sounds intuitively wrong. Don't use "jump" and then describe the ship accelerating, and don't use hyperspace travel if it flies into a big metal ring and immediately emerges from a similar ring somewhere else. Unless of course, if you previously mentioned that the rings are connected by a wormhole through hyperspace or some other technobabble. ;)
In short: if it sounds similar to the actual description of what happens, the name is probably right. That's how the terms got made up in the first place.

Addendum: Prjoect Rho has The Canonical List Of StarDrives. But it's a list based on function, there is no standard what to name those various drives, although as mentioned above, some names are more fitting than others.
 
Last edited:

small axe

memento mori
Super Member
Registered
Joined
Apr 6, 2007
Messages
1,940
Reaction score
261
That too cool !!! Thanks for that huge help, Lhun!

Addendum: Prjoect Rho has The Canonical List Of StarDrives.

... is an utterly amazing SF resource! :)

Every writer and sf fan has to bow to something like that! Great wealth there!
 

Meatball

Registered
Joined
Jun 13, 2010
Messages
7
Reaction score
0
Location
North Carolina
Project Rho is awesome. I could spend way too much time lost in those pages. I appreciate everyone's input!
 

TMA-1

Super Member
Registered
Joined
May 21, 2005
Messages
166
Reaction score
7
Age
46
Location
Sweden
Given that wormholes are allowed by the laws of nature as we know them today, they are still better to use than total handwaving, in my view. You also get to avoid FTL, which avoids a number of other problems.

But if you want ultrahard SF, then I don't know of anything that would allow anything better than simply going near the speed of light.
 

FOTSGreg

Today is your last day.
Super Member
Registered
Joined
Jun 5, 2007
Messages
7,760
Reaction score
947
Location
A land where FTL travel is possible and horrible t
Website
Www.fire-on-the-suns.com
Project Rho is indeed awesome and was put together by my friend Winchell Chung and a few others. Winch has done a great job on the site answering thousands of questions for thousands of people.

In my (seemingly never to end or be completed) space opera and related stories I use a network of ancient alien artifacts that appear to link the entire galaxy together (well, actually it's more like 80-90 percent) and no one (except a select handful of sentients the galaxy over) knows how it works. It just does. In one short story I'm working on, one of the few who does know how the "network" was intended to work (note the difference - he doesn't know how it works, just how it was intended to work) tells another character that "I think it might be another whole universe in there".

It's not necessary to explain the "physics" of your drive(s) to the reader. It's just necessary toremain internally-consistent when someone in your story is talking about it or it's being explained (and info dumps are not required).
 

pdknz

Having way too much fun
Super Member
Registered
Joined
Mar 5, 2010
Messages
157
Reaction score
17
Location
You wouldn't believe me if I told you.
Well, it's been said before, but the best approach seems to be to start with the requirements of the plot, and cut the pseudoscience to fit. I've mentioned the over the top performance of the Star Wars artifacts before, but if you look at the plot, it sorta makes sense. One of the things that has always bothered me about TV and movie stuff is the outrageous lack or proportion they use, where there are street cones in space, face to face meetings of immensely powerful spaceships only a few yards apart, and relative velocities between passing vehicles that would be under the speed limit in a school zone. It all serves the story, at the cost of credibility.

I guess we are talking about what's the most believable class of handwavium here, and the answer seems to be that it depends on the plot.

One of my favorite series is the Firefly/Serenity stuff, and they sort of make a shot at pretending that it all takes place in a single large planetary system. That still doesn't work, of course, but the characters save the story.