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[Simmura McCrea]

Also: water requires gravity to flow, and gravity only pulls in one direction, it's impossible to expect gravity to pull in two different directions at it's own discretion.

Not even going to touch your suedo-philosophy, but this quoted section is false. The Earth has a gravitational pull towards its centre. So does the Moon. And the Sun. So does your mother. And you. And that fly over there. Everything with mass has a gravitational pull. They're all pulling towards their centres. Gravity is pulling all over the place at once.

Negative. Gravity doesn't 'fight' with one another in your proposed gravitational tug-of-war. Either one side pulls, the other side pulls, or both sides hold an object in stasis. The only effect the earth has on the sun is keeping you from being pulled towards it. You can change distance from one field or another, or increase one fields power over another, but the above still holds true.

Physics fail. Say I'm standing on the surface of the earth, directly under the moon. Both are pulling me towards them, the earth obviously doing so more due to its larger mass and closer distance. As I move towards the moon, the earth's force decreases and the moon's increases until I reach the Lagrange point, where they cancel out, then the moon's pull becomes the dominant pull. At all times, both bodies are pulling at me.

[tolkafox]

Either one side pulls, the other side pulls, or both sides hold an object in stasis.

So you're just repeating what I've said in a scenario. The purpose of this is...? Are you agreeing with me, or are you trying to argue with me by agreeing with me? O.o

[Simmura McCrea]

Either one side pulls, the other side pulls, or both sides hold an object in stasis.

So you're just repeating what I've said in a scenario. The purpose of this is...? Are you agreeing with me, or are you trying to argue with me by agreeing with me? O.o

The section you've quoted implies that they aren't both pulling at you at once unless they cancel out. This is entirely false. If this isn't what you meant, you should reword it.

[JimiD]

I thought mass bends Spacetime, and the curved Spacetime results in the effect of gravity.  But relativity is so odd, I may have misunderstood.  But it would mean that there are not two forces acting on you, but movement through one Spacetime. But which can be described as two forces.

Again, a long time since I thought I understood relativity.

[Simmura McCrea]

I'm not involving relativity and spacetime. Shit's whack, yo.

[JohnieRWilkins]

I thought mass bends Spacetime, and the curved Spacetime results in the effect of gravity.  But relativity is so odd, I may have misunderstood.  But it would mean that there are not two forces acting on you, but movement through one Spacetime. But which can be described as two forces.

Again, a long time since I thought I understood relativity.

There are still very separate forces acting on you if you observe from our 3 dimensions, but when you view it from a 4d spacetime graph, you get a bend in the spacetime.

[MonkeyHead]

Ugh. Speaking as a Physicist, some of the posts in this thread make my beard cry.

[tolkafox]

Either one side pulls, the other side pulls, or both sides hold an object in stasis.

So you're just repeating what I've said in a scenario. The purpose of this is...? Are you agreeing with me, or are you trying to argue with me by agreeing with me? O.o

The section you've quoted implies that they aren't both pulling at you at once unless they cancel out. This is entirely false. If this isn't what you meant, you should reword it.

Yes, infinite sources of gravity can pull you at one time, but only the dominant force will actually pull you to it. This is what I meant, thus water can't be pulled in two different directions in the same area by gravity alone. This is excluding the moons pull on our oceans of course, it cheats by rotating around us in an elliptical motion.

Ugh. Speaking as a Physicist, some of the posts in this thread make my beard cry.

Wait, physicists are real? I thought they were a myth created by my parents to keep me from having sex too early.

[G-Flex]

Yes, infinite sources of gravity can pull you at one time, but only the dominant force will actually pull you to it. This is what I meant, thus water can't be pulled in two different directions in the same area by gravity alone. This is excluding the moons pull on our oceans of course, it cheats by rotating around us in an elliptical motion.

This is a horrifyingly over-simplistic and naive interpretation of force summing.

You can have a multitude of gravitational forces acting upon you at once (and in fact always do). Which direction you're "pulled" in, and how hard, is determined by the sum of those force vectors, just like with any other force. They all contribute. You can't just ignore all but the "strongest" one. A weaker, secondary force will mess with the direction and/or magnitude of the final net force vector acting upon you. So yes, something can be "pulled in two directions at once"; it just results in the net "pull" being in one direction somewhere between either of the originals (unless they're total opposites, of course, in which case it's just in one of those directions but less so).

If you guys are going to argue about this, you might as well know the simple math behind forces.

Of course, this is complicated further by the fact that the objects exerting gravity on you are also exerting it on each other.

[tolkafox]

This is a horrifyingly over-simplistic and naive interpretation of force summing.

I'm sorry, is it required to be complex instead of simple? O.o Last I checked we were on a forum for players of DF, not a forum for MIT physicists. As such, I believe it would be best to keep things simple for passerby's to understand, and not over complicate things for the satisfaction of one's ego.

You can have a multitude of gravitational forces acting upon you at once (and in fact always do). Which direction you're "pulled" in, and how hard, is determined by the sum of those force vectors, just like with any other force. They all contribute. You can't just ignore all but the "strongest" one. A weaker, secondary force will mess with the direction and/or magnitude of the final net force vector acting upon you. So yes, something can be "pulled in two directions at once"; it just results in the net "pull" being in one direction somewhere between either of the originals (unless they're total opposites, of course, in which case it's just in one of those directions but less so).

Wow, so a multitude of gravitational forces results in you being pulled in one direction. Brilliant. I think I already said that, though.

Edit: You should know that this is all being copied from an old post in another forum. The post is about 11 years old, so if it seems naive and simplistic that's because it is, and I have no intention of changing the content of it outside of editing for relevance. I admit though, the argument was more fun 11 years ago then it is now.

[G-Flex]

Wow, so a multitude of gravitational forces results in you being pulled in one direction. Brilliant. I think I already said that, though.

No, you said that "only the dominant force will actually pull you to it". This is wrong, even if we're defining "dominant" as the one exerting the force of greatest magnitude. You're obviously talking about situations where there may be many forces acting at once, and a number of smaller forces can easily overpower a greater force. Also, even in a system with only two gravitational forces acting upon you, it's very, very easy for one of those forces to throw the other very off-kilter in terms of magnitude and direction such that you aren't really being attracted to either very directly.


This might seem pedantic, but the way you worded it makes it sound like no matter how many forces you have, you only need to consider the strongest one, which is, well, wrong, and will lead to very inaccurate results in any circumstance except ones where the strongest force overpowers the others so much that the others are effectively irrelevant.

[Sheb]

Well, actually both sides always pulls. Once just pull harder than the other.

[G-Flex]

Right, and unless they're either in the same direction from you or in completely opposite directions from you, the net pull will be in neither of their directions.

[tolkafox]

No, you said that "only the dominant force will actually pull you to it". This is wrong, even if we're defining "dominant" as the one exerting the force of greatest magnitude. You're obviously talking about situations where there may be many forces acting at once, and a number of smaller forces can easily overpower a greater force.

Thus making those 'number of smaller forces' the dominant force. The dominant force is the force that is pulling you dominantly.

Also, even in a system with only two gravitational forces acting upon you, it's very, very easy for one of those forces to throw the other very off-kilter in terms of magnitude and direction such that you aren't really being attracted to either very directly.

Either one side pulls, the other side pulls, or both sides hold an object in stasis.

That's what is sounds like you're saying. If not, you need to reword it.

This might seem pedantic, but the way you worded it makes it sound like no matter how many forces you have, you only need to consider the strongest one, which is, well, wrong, and will lead to very inaccurate results in any circumstance except ones where the strongest force overpowers the others so much that the others are effectively irrelevant.

Either one side pulls an object towards it, the other side pulls an object towards it, or both sides hold an object in stasis.

I'm sorry, but I'm use to arguing with people who have a grasp on inferring meanings from sentences.

or both sides hold an object in stasis.

Both sides can't hold an object in stasis if they weren't both pulling the object at the same time. Since they are in the same sentence you should have been able to deduce this. I could have reworded these for 'personal clarity'.

But then it wouldn't be any fun

[G-Flex]

No, you said that "only the dominant force will actually pull you to it". This is wrong, even if we're defining "dominant" as the one exerting the force of greatest magnitude. You're obviously talking about situations where there may be many forces acting at once, and a number of smaller forces can easily overpower a greater force.

Thus making those 'number of smaller forces' the dominant force. The dominant force is the force that is pulling you dominantly.

Then you're effectively saying "the only force that acts on you is the net force, which should be obvious, and which isn't really one of the original forces anyway, even though my language is making it sound like it is".
 

That's what is sounds like you're saying. If not, you need to reword it.

No, that's not what I meant. The object can be pulled, but in a direction that isn't immediately toward either object attracting it. Force vectors, people. If you have one force pulling you northwest and another pulling you northeast, you'll be pulled north (assuming they're of equal magnitude; you get the gist).

I'm sorry, but I'm use to arguing with people who have a grasp on inferring meanings from sentences.

That sentence has a meaning that could very much be inferred as "either you'll go towards one source of gravity, toward the other source of gravity, or go nowhere at all", which isn't how reality works.