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[Thecard]

They are?  How are you sure?

[Aseaheru]

i think i read it somewhere...

Spoiler (click to show/hide)

was it in that hard-sifi book...

[GreatWyrmGold]

I would have thought that, no matter what, the whole station would stop rotating after a while. I brought this up earlier, and it wasn't addressed.

Because it's so obvious that it's hard to find the words to address it.  An object rotating in a vacuum doesn't stop rotating after a while.  What do you want us to say?  Take physics 101?

It just seems like it would be violating thermodynamics. Gravity and the stuff imitating it is basically acceleration, and it doesn't seem like you should be able to set up a source of infinite acceleration in the opposite direction of gravity without constantly inputting at least some energy.

[Aseaheru]

not for acceleration.
its a newton's law.

[Thecard]

Constant speed is not acceleration.  Acceleration and deceleration are deviations from constant speed, through action on a body.

Constant motion is perpetual motion.  Gravity is one example of an uneven force that stops movement.
On that note, in zero-g environments, motion is constant.  Deceleration will only occur through friction and shit.

But zero-g is impossible, there will always be some kind of gravitational pull, though it may be almost completely non-existent.  So yes, it should stop because of gravity.  A vacuum does not mean an absence of gravity, last I checked.

[Aseaheru]

yes.

[GreatWyrmGold]

Okay, I misunderstood the Laws of Thermodynamics then.

[kaijyuu]

* kaijyuu twitches at the word "deceleration."

It's acceleration no matter what! "Slowing down" is just a frame of reference thing; no matter what, it's accelerating if it changes speeds.

[MonkeyHead]

... or direction. Velocity is a vector people!

[Thecard]

Ah.  Again, I'm not very good at this.  I just felt like people were forgetting there are other unequal forces besides friction.

[mainiac]

But zero-g is impossible, there will always be some kind of gravitational pull, though it may be almost completely non-existent.  So yes, it should stop because of gravity.  A vacuum does not mean an absence of gravity, last I checked.

When was the last time you felt the gravitational effects of the sun?  They are stronger then the effects of the earth where you are sitting right now.  But you feel the gravity of the earth not the sun because the earth is pushing back against you while you are in free orbit around the earth.  A zero-g environment doesn't mean no gravity, it means no normal force due to gravity.

[Thecard]

When was the last time you felt the gravitational effects of the sun?  They are stronger then the effects of the earth where you are sitting right now.  But you feel the gravity of the earth not the sun because the earth is pushing back against you while you are in free orbit around the earth.  A zero-g environment doesn't mean no gravity, it means no normal force due to gravity.

Earth's gravity is affecting me much more than the Sun's gravity.  This is illustrated by me not flying towards a fiery gaseous death.

[Aseaheru]

and the earth is affected by the sun's gravity, but it is negated by the speed it is falling twards it.

[Flare]

simpler would be to dock in the middle

That was what my entire posts have been recommending .

I can easily see a problem with the 'whole station is rotating' idea.

Namely, it's be harder for something to dock with it. Not impossible, but a lot harder.
It's be like Elite. A lot of dying. Or at least, it would be like that with me.

Why not have the dock in the middle of the flywheel. The docking apparatus just needs to be place on ball bearings and a motor to counter act the small amount of friction and you now a stationary, self adjustable dock.

Friction. Unless you want to spend a load of fuel keeping the station rotating, the central part will, eventually, slow down the whole station.

It is true, movement inside of this ring craft will have a bearing on whether it keeps spinning or not. The donut hole dock in the middle is no exception. The important thing to keep in mind is that rotating on an axis in a near zero gravity environment can be achieve easily by using gyros. In other words, the mechanisms that keep vehicles that shouldn't be standing up, standing up. Like the things in segways, and the one wheeled bike. If you have a power generator on board the ring-craft, powering gyros would not be a problem. As such, whatever small constant force is causing it to slow down can be counteracted.

They don't turn rotation among the axes into forward momentum though, doing so would violate physics. It's like as if I were floating in near zero-g and I rapidly swing my legs about. I can't change my trajectory or anything if there's no air for me to push myself from, but I will be able to cause myself to spin myself.

[GreatWyrmGold]

But zero-g is impossible, there will always be some kind of gravitational pull, though it may be almost completely non-existent.  So yes, it should stop because of gravity.  A vacuum does not mean an absence of gravity, last I checked.

When was the last time you felt the gravitational effects of the sun?  They are stronger then the effects of the earth where you are sitting right now.  But you feel the gravity of the earth not the sun because the earth is pushing back against you while you are in free orbit around the earth.  A zero-g environment doesn't mean no gravity, it means no normal force due to gravity.

Problem is, on Earth it's drowned out by the Earth's gravity, analogous to how the Sun's light drowns out the starlight in the daytime.
Actually being in outer space lets those distant things affect you more. A LOT more; if you're several thousand miles above Earth's surface, Earth's gravity is only about a quarter as strong, and around the Moon's orbit it's hundreds of times weaker.

They don't turn rotation among the axes into forward momentum though, doing so would violate physics. It's like as if I were floating in near zero-g and I rapidly swing my legs about. I can't change my trajectory or anything if there's no air for me to push myself from, but I will be able to cause myself to spin myself.

Which leads me to further confusion for me...
How exactly can you simulate the acceleration from gravity, against the pull of real gravity, without expending any energy?