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sideways
2003-Sep-18, 06:45 PM
Growing up watching SF shows with folks on spaceships that have perfect artificial gravity that doesn't require a rotating spaceship has compelled me to believe that such systems should be sought despite the very real possibility that they may be impossible to build. That said, does anyone have any theories on how to produce such "electromagnetic" articificial gravity systems?
:-k

kilopi
2003-Sep-18, 07:08 PM
Growing up watching SF shows with folks on spaceships that have perfect artificial gravity that doesn't require a rotating spaceship has compelled me to believe that such systems should be sought despite the very real possibility that they may be impossible to build.
Also saves on the film budget.

In real life, all you have to do is warp the local space. That's all.

Cougar
2003-Sep-18, 09:08 PM
...does anyone have any theories on how to produce such "electromagnetic" articificial gravity systems?

Magnets in the floor and... iron pants? (Better wear suspenders.)

But seriously, magnetism attracts in an inverse-square fashion. Wouldn't a certain magnetic strength be similar to gravity? (Assuming your clothes carried a bunch of magnetic or steel "attachments".) On second thought, 1 g due to earth gravity pretty much covers your whole body. If a magnet in the floor attracted your feet at 1 g, that would leave you, uh, lightheaded, so to speak.

Madcat
2003-Sep-18, 09:15 PM
Yes but no. Magnets would pull, as you said on clothing made of ferrous material. It wouldn't pull on you. Your blood has iron in it, sure, but it's not magnetic because of the way it forms chemical compounds in your blood. Oh... waitaminnt, you didn't think it would pull on your blood, did you? #-o I've had to explain that before...

Actually it went kind of like: Magneto could not crush Gambit with the iron in his blood! Could too! COULD NOT! COULD TOO! I'M LEAVING! FINE!

Humphrey
2003-Sep-18, 09:44 PM
I am strongly against all forms of artificialy gravity.

Why? you ask. Well let me tell you.

How would you think the planets and other objects in our solar system would react if a earth sized gravity well suddenly appeared inside the solar system?

wedgebert
2003-Sep-18, 10:07 PM
Hmm, I guess if you could generate gravity, you might be able to cancel gravity out as well.

So that way you could cancel the gravity at the hull of your ship. Among other things, this would keep your ships from pulling all the nearby space debris (including your other ships) into it.

mike alexander
2003-Sep-18, 11:10 PM
If you had magnets in the floor, wouldn't they be in the ceiling on the deck below? You'd have to have a ranch-style spaceship. (Flat, if it was English).

wedgebert
2003-Sep-19, 01:45 AM
Magnets wouldn't work very well. Sure, it might keep YOU stuck to the ground (assuming you had mangetic clothing), but other things will still float around.

That is unless you like a lot of iron in your coffee

AstroSmurf
2003-Sep-19, 08:12 AM
How would you think the planets and other objects in our solar system would react if a earth sized gravity well suddenly appeared inside the solar system? Doesn't have to be Earth-sized, just a teensy one close to your ship. It's not the depth of the gravity well that determines how much gravity you feel, it's the slope.

Paul Beardsley
2003-Sep-19, 09:49 AM
I can understand why the makers of films and TV shows have generally given their spaceships artificial gravity - budget an' all that. But I think the overall effect has been quite harmful - a powerful piece of negative education.

I've read science fiction books and listen to science fiction radio plays set on spaceships - often primitive or derelict craft - where the budgetary limitations are not a problem. And they've still got artificial gravity. Or rather, it hasn't occurred to the author that people aren't going to weigh anything in space. Audio and novel spin-offs of the old TV series Doctor Who are especially guilty of this sheer lack of thought.

Donnie B.
2003-Sep-19, 11:39 AM
To expand a bit on AstroSmurf's answer...

If you're looking for a science-fiction form of artificial gravity, all you have to do is postulate a technology that can induce a G-field with something other than an inverse-square characteristic. This allows you to "concentrate" the gravity into a narrower region -- say, one G at torso level, but a fraction of a G at ceiling height. If your control is fine enough, you might be able to get a fairly uniform G-field in the living space, with rapid falloff outside the region of interest. (It would probably be harder to make the effect one-sided, though. Maybe you could build your ship so that each "floor" was two sided, so the direction of "up" would alternate as you moved from deck to deck.)

Of course, we have no clue how such a technology might work... but then, Caesar would say the same about a doorbell.

On the hopeful side, there are certain analogies to this in the electronics arena. In the most basic case, electromagnetic radiation is emitted in a spherical inverse-square field. But it's quite possible to modify this by means of antenna design. Even a simple antenna can produce (or receive) signals in a non-spherical, lobed pattern, concentrating its energy (or sensitivity) in certain directions. More complicated phased arrays can produce a steerable "beam". Perhaps that's what the Trek grav emitters are: a phased array that produces a desired field pattern within the starship, with little "leakage" beyond the hull.

But I'm not quite ready to patent the concept... :D 8)

Astronot
2003-Sep-19, 01:25 PM
It seems perfect feasible, for Sci-Fi purposes, to have artificial gravity in a space ship. A reasonable arrangement would be to have omni directional gravity generators on the “lowest” deck of the ship for any particular cross section. Gravity insulators should be built into the hull. The generators need not follow the inverse square law, which need only apply to natural gravity. If there is some fall off over distance it could be boosted by more generators placed periodically throughout the ship. This is Sci-Fi after all, where when authors are free to extrapolate from known science into the unknown.

What has always bugged me about Star Trek is that the gravity system is more robust than life support. You can fly a ship by being strapped into the seat but you die if the air runs out. Also, why do they only get a few minutes to live when the life support fails, the ships always have a large volume that should have breathable air for some time. I know dramatic effects and budget, but still......

Humphrey
2003-Sep-19, 01:37 PM
What mystifies me even more is the fall off rate for gravity. The second you step onto the hull of the ship gravity cuts out for you. See First contact for a good example.

Madcat
2003-Sep-19, 01:52 PM
As far as I know, the only thing that generates gravity is mass. You could generate mass, but that takes lots and lots of E. Hey, I'm gonna go out on a limb here and posit that if artificial gravity is possible, it will require at least as much energy as would be contained in the matter of a mass with the same gravity well. :) That should be a lot too.

Avatar28
2003-Sep-19, 06:00 PM
Well, we know that boeing has been doing antigrav research for the military in their black ops programs So who knows what sort of tricks they may have up their sleeve or what they may have learned that they're not sharing.

Betenoire
2003-Sep-19, 08:05 PM
Did Boeing steal that technology from the Nazis?

On the idea of having a big gravity well suddenly show up in system...

I wonder what after effects the Death Star's mere presence would have in a system? I mean, hyper drive in, suddenly there's something not just pretty darn massive, but also running some serious arti-grav systems.

Avatar28
2003-Sep-19, 08:50 PM
Did Boeing steal that technology from the Nazis?



No idea. But they admitted a year or so ago that they were involved in serious anti-grav research. They wouldn't comment on what, if anything, they had come up with, though.

My guess is that if they haven't developed whatever they've got (if anything) then it probably came from extraterresterial technology. :-)

Betenoire
2003-Sep-22, 04:28 PM
Then we must arm ourselves to kill them, because ETs are ALWAYS out to kill us and take our women for love slaves!

Avatar28
2003-Sep-22, 06:23 PM
Then we must arm ourselves to kill them, because ETs are ALWAYS out to kill us and take our women for love slaves!

I thought that was James Tiberius Kirk that did that... :-)

Betenoire
2003-Sep-22, 06:27 PM
Yeah, but he's a hero.

Sigma_Orionis
2003-Sep-22, 06:43 PM
Did Boeing steal that technology from the Nazis?



No idea. But they admitted a year or so ago that they were involved in serious anti-grav research. They wouldn't comment on what, if anything, they had come up with, though.

My guess is that if they haven't developed whatever they've got (if anything) then it probably came from extraterresterial technology. :-)

From what I could find (see here (http://news.bbc.co.uk/1/hi/sci/tech/2157975.stm)) Boeing seems to have tried to duplicate the experiment done by a russian called Yevgeny Podkletnov whom claim he managed to "shield" objects from the pull of gravity or something like that. AFAIK no one has been able to duplicate the experiment so I guess it's in the same category as Cold Fusion