Artificial Gravity...

[Sarah]

Love it? Hate it?

Depends on delivery for me. I get that it often facilitates a more digestible atmosphere for us as readers, but I also want the author to have devoted at least some time to explaining the technology in their story. I guess I'm just not a big fan of, "let there be gravity" in sci fi novels. I'm a big techy... I want to know how there's gravity (that way when I finish building my Low Orbit Spa and Fitness Center, I'll know how to keep people from bouncing off the ceiling).

[Armand]

Interesting point... I think we expect sci-fi stories to include artificial gravity simply because it makes things easier to understand and visualize (especially for movies/ TV) , however it would be kind of cool to imagine a spacecraft without gravity and characters "sitting" on the ceiling, walls or floor, looking very MC Escheresque while engaged in a conversation.

[Trike]

Depends on the hardness of the story. Niven's Known Space eventually has gravity generators, which he takes to its logical conclusion, but that series is pretty solidly in the Science Fantasy side of the genre. So in a Star Wars/Star Trek equivalent story, I don't really care too much.

If it has aspirations to be harder SF with serious extrapolation, then I like an explanation. But I find that books with that intention generally don't use artificial gravity aside from centripetal force. I actually can't think of one offhand that uses some form of generated gravity.

[Humberto]

In general any rotating cylinder produces artificial gravity. Can be as large as necessary.

[Trike]

Humberto wrote: "In general any rotating cylinder produces artificial gravity. Can be as large as necessary."

This is why my top sticks to my cat.

[Adriaan]

Indeed, artificial gravity is one of the 'tells' that separate Hard-SF from Space Fantasy for me, in terms of how it's generated & explained. (Not that I dislike fantasy)

For a great book where the artificial gravity is a key plot point, check out: Endgame Enigma. I've also generally liked how Cherryh has handled gravity issues in her merchanter/compact universe. Gives it a bit of a gritty feel without overdoing the detail.

[Armand]

I think an early HG Wells story involves the discovery of "gravity rays"... A clever scientist finds a material that blocks the gravity rays and then builds a cube with all sides blocked from gravity except the "Moonward" side and commences on the first journey to the moon... this might have been an HG Wells story, honestly I read it about 25 years ago, so my memory is fuzzy.

[Jim]

Armand wrote: "I think an early HG Wells story involves the discovery of "gravity rays"... A clever scientist finds a material that blocks the gravity rays and then builds a cube with all sides blocked from gravi..."

I think I remember the book but yes, it was over thirty years for me. But the word cavorite came to mind for the material and it's
The First Men in the Moon

[John]

Just picked up on this post, and it touches a nerve since the protagonists in my Lunar Free State stories use artificially-generated gravity as a propulsion system for their spacecraft. Use it? Heck, they depend on it, because it's the one bit of technology that sets them apart from everyone else and lets them do what they do.

I try to put some science into the mix; but it's difficult. One of the reasons artificial gravity (or "anti-gravity") is so attractive for SF writers is that gravity is one of the least-understood forces in the universe, yet it's the "glue" that holds the universe together. Physicist Lisa Randall has written some interesting stuff on the subject, but even she admits there are some things about it that don't make sense. One of the questions she asks is why is gravity (in its natural state) such a weak force.

Weak? Hey, it keeps the planets in their orbits. Yes, but think about this: it takes a mass the size of planet Earth to make you weigh whatever you weigh, i.e. to generate the hundred or so pounds of gravitational force that it takes to keep you anchored to the ground.

Randall's comment (delivered in a lecture I heard) was that maybe what we perceive as gravity is actually the manifestation in three dimensions of what is really a much stronger force in an n-dimensional frame.

Now... if that doesn't make your head hurt just thinking about the math involved, imagine how much fodder there is for SF writers in that statement...
;-)

[Trike]

I quite agree with that, John. There seems to be no true consensus on gravity's source; I've even seen serious proposals that it's a property of dark matter.

I think someone could postulate a rigorous explanation for gravity (and anti-gravity) for Hard SF. For some reason authors rarely do so. I think one of the areas where that speculation falls down, though, is that they don't then use their anti-gravity (or gravity-increasing) tools anywhere except onboard spaceships. But why wouldn't someone use it for manufacturing? Anti-grav is perfect for all sorts of processes... and you could have all kinds of industrial accidents with it. Or murrrderrr.

[Trike]

Randolph wrote: "This thread is too heavy for me."

"There's that word again: heavy. Why are things so heavy in the future? Is there a problem with the earth's gravitational pull?"

[John]

Trike wrote: " I think one of the areas where that speculation falls down, though, is that they don't then use their anti-gravity (or gravity-increasing) tools anywhere except onboard spaceships..."

David Weber is one of the few SF writers who use gravity in multiple ways (in one story, he even uses it as a backstop on a shooting range, to keep bullets from going far beyond the targets); but you are absolutely right -- most writers don't seem to realize that if you can master gravity, there are thousands of applications for it. And of course, Hollywood is the worst -- they obviously have artificial gravity aboard space ships, because people walk around on the decks and something is holding them down -- but there is no mention of it, and it doesn't seem to get used for anything else, not even as a source of propulsion.

[Trike]

It only really bothers me when authors use anti-gravity the way we'd use a motor. Anti-grav cars (or worse, belts), without thinking of all the implications of that sort of ubiquitous technology. Using it as wheelchairs or crutches is just the start: athletes, mountain climbers, birthing suites, amusement park rides, supports for infirm pets or livestock, the list is nearly endless.

If it's something that's too big and complex to be used as anything other than on a large starship -- akin to a nuclear power plant -- then as long as they state that, I'm fine with it being confined to that purpose.

[Armand]

Trike wrote: "Using it as wheelchairs or crutches is just the start: athletes, mountain climbers, birthing suites, amusement park rides, supports for infirm pets or livestock, the list is nearly endless...."

good point, and don't forget waterless swimming pools!

[Trike]

Armand wrote: "good point, and don't forget waterless swimming pools!"

The perfect solution for people with aquaphobia! Although maybe not for people with a fear of falling.

[Humberto]

In my opinion, antigravity is difficult to achieve. I would expect the overall level of technology to be quite advanced. That means no Victorian machines.

Flying cars do not need antigravity, ultralight materials, better aerodynamics (like formula 1 cars - 4g at 200 kph), electro hydrodynamic thrust and good batteries (maybe 15 yrs away) will do it.
H

[John]

Armand wrote: "Trike wrote: "Using it as wheelchairs or crutches is just the start: athletes, mountain climbers, birthing suites, amusement park rides, supports for infirm pets or livestock, the list is nearly en..."

How about zero-gee basketball/soccer/hockey/tennis... or some entirely new sports played in three dimensions. For that matter, can you imagine a game of 3-D billiards?

David Weber also mentions "counter-grav" belts, used by rock climbers, hang gliders, etc. as safety devices.

In my books (at least the first two) my protagonists haven't quite gotten that far. Gravity technology is new to them, and like many new technologies it is still cumbersome and power-hungry. It's OK for spacecraft propulsion (BIG spacecraft, that can afford the space for a fusion reactor to produce the necessary power) and internal gravity (on ships, and in low-gravity environments such as the Moon); but we haven't yet got it down to what anyone would call "portable."

Any technology goes through a period of evolutionary development. Early electronics used power-hungry, heat producing vacuum tubes, and the first attempts to build computers resulted in room-sized monsters that required extra air conditioning just to keep them cool. Now, half a century later, we have smartphones with orders of magnitude more "computer power" than was used in the spacecraft that took the Apollo missions to the Moon.

So... early gravity technology? OK, it'll get you to the Moon in a few hours; but it's not quite ready for the family car yet. :-)

[Trike]

We know less about gravity than most things. I could imagine there might be a number of potential methods to generate it. Black holes or an ultra-thin layer of neutronium, maybe.

[John]

Clive, I think you need to go back and look at Einstein again, because that isn't exactly what he said. Better yet, read some more recent stuff -- Stephen Hawking, Lisa Randall, etc.

Gravity does exist, and some very smart people are trying to figure out how it works.