A friend and I have been discussing the Elemental Plane of Water, which is supposed to consist of only (or mostly...

It's magic water. Pressure varies, and islands float in it.

So, how would anything move through that place?

On an infinite volume area though, you'd still be able to move thanks to internal friction forces. Just because there's no gravity doesn't mean hydrogen bonding and Van der Waals forces stop existing.

You can create temporary local pressure and force differentials.

Water isn't an element reeeeeeeeeee

But no seriously to answer your question, physics has no problem with an infinite plane consisting entirely of water. Think of this demonstration of infinity:
A hotel with infinitely many rooms is full. There are more rooms in this hotel then there are atoms in our universe. And every single one of them is occupied. Somehow. A guest rocks up at the hotel and asks if there's space. The receptionist says sure, no problem, we'll just have to clear a room for you. So he goes with the new guest to room 1 of the hotel. He asks the guest in room one to move over to room 2 and tell the guest in room 2 to move over to room 3, and so on. Assuming every guest in the hotel is perfectly obliging in this request, there is literally no issue with this. For all of eternity, there will always be exactly one guest somewhere in the hotel moving into the next room. The hotel, despite being full, is fully capable of taking in another guest.

This is what infinity means. So if you have an infinite plane of water all sorts of interesting things start happening. Theoretically, if there was no friction, any wave you start would continue indefinitely into the distance, but realistically it will eventually dissipate into (a tiny amount of) heat energy. There will be no gravity because there is a perfectly equal amount of mass in every direction (if you did any maths in school, an interesting factoid is that a graph of sin(x) or cos(x) is actually symmetrical about every single point that equals 1 or negative 1 because it continues infinitely in both the positive and negative direction. Infinitely many parallel axes of symmetry!). There is no pressure because there is no gravity. You float in place because there is no gravity. You can ask me different scenarios and I can help you try to understand what would happen.

t. currently studying mechanical engineering, which includes a ton of fluid dynamics.

If it's literally infinite then there's no reason why there'd be any gravity. Things like up and down would have no meaning in the elemental plane of water. It's functionally pretty much identical to being in space, except you can propel yourself around way more easily because you can push away the water to move (i.e. swim, except in any direction you want).

It's magic, you ain't gotta explain shit.

>Thoughts?
Why would you assume that a universe full of water would exhibit the same physical properties as a layer of water covering a terrestrial planet in our universe?

If there is no gravity in this plane, then pressure wouldn't vary linearly with depth

So you are saying that the magical infinite dimension made of nothing but water doesn't obey physics.
No shit, you don't need to explain in any scientific terms anything that happens in a FANTASY game.
If you want crushing depths have em if you don't then don't it is all magical bullshit anyway

Christ, I wonder what you think about the Elemental Plane of Fire.

And here we see a traveler from the elemental plane of shit nobody cares about. Creating a localized disturbance of people pretending to be smarter than they are.

There would be no net force but there would still be force. So most likely you would be pulled apart by opposing forces.

You do realize Gravity is an inherent property of mass? There would still be gravity.

Being another plane of existence, the same forces that apply on the material plane don't entirely apply on the elemental plane of water. There are forces in play that allow it to function the way it does, but would most likely tear apart the material plane if they were in effect there.

>Gravity is an inherent property of mass
Sure, on the material plane.
The elemental planes are literally entirely separate realities. What makes you think they would abide by the same physical laws?

The fact that objects don't burst apart into a spray of free particles and radiation upon planeshifting in and people can fight and move mostly fine with minor acclimation implies that physics are universally constant.

Somewhat, but not entirely. The 3.5 DMG discusses some of the planes, and some of them have sentient gravity. Hell, some of them have malevolent gravity. So, in places like these, not only does gravity have a sapient consciousness, but it hates you, and actively wants to make you suffer.

Thank god just it's Gravity being a bitch, that's easily survivable.
Any of the other forces acting up and we'd be FUCKED.

aight so here's the dealio

You're a filthy human from the filthy Middle Realm

So when you open a gate to the Plane of Water, you end up in Middle-Tilted Water Realm,It's basically just a big ocean. In fact, all water in your filthy Middle-Realm IS the Plane of water, it's just the Plane of Water so heavily Middle-Tilted that, well, never mind, you wouldn't get it. But all your idea of things being other things is wrong, and I hope you feel bad about it.

Now, there are directions you can go in, but they're not really up and down, left and right, or anything like that. They're 'tilts' towards other planes.

Air-Tilt in Water-Realm will take you towards a 'surface' of clouds, fog, torrential rain. Earth-Tilt will take you towards cloudy water, then ooze and muck and mud, and so on. Keep going far enough and you end up not in Air-Tilted Water, but Water-Tilted Air. The same's true for other stuff, like Fire, Ice, Blood, Skeleton, Scorpion, Broomstick, Gravity, Mumbling, Loss Aversion, Tilt-Tilt-Repeating, whatever, you get it. Well you don't, but you think you do.

There's a lotta tilt directions. Too many to imagine, if you're a filthy human from the filthy Middle Realm. So that's why you consult elementals and not filthy humans about this.

Now tilt yourself the fuck out of my fountain!

Yeah, but there would be no center of gravity.

It'd just be very wet version of outer space.

I'm assuming malevolent electromagnetism would just cause everyone to disintegrate into photons, but what about malevolent nuclear forces?

They'd cause everybody to disintegrate into either nuclear explosions or just sprays of subatomic particles depending on how they went wonky.

since there is an infinite amount of water extending in all directions, it would be pitch black.
Ignoring the obvious problem of the infinite mass of the water creating an all-consuming black hole, you could assume there is no orientable gravity whatsoever- consider ever point-mass would be pulling you in its own direction and have a counterpoint on the other side of you. It'd all cancel out and you would feel weightless. Since there should be infinite space, there would be no pressure either.

tl;dr: infinite water is basically like space, but wetter.

The question then becomes: Why would it be infinite H20 everywhere? Why not a plane of ice planets seperated in the void, with liquid water in some places. Air made of steam and water vapor. A plane of pure liquid water is boring compared to all of water's myriad forms. The elemental plane of water would need to showcase ALL of its forms- ice, steam, rain, hail, snow, waterfalls, whirlpools, maelstroms, etc.

god your fucking stupid

MFW actually studying physics and reading this thread.

>No net force
>Pulled apart
You realise gravity acts on every single molecule in your body right? And given the nature of infinity, the only difference in the amount of water on one side of your body to the other is the amount of water displaced by your body. Which would have an utterly negligible effect on the gravity experienced by that particular part of your body. In short, the forces "pulling you apart" would be so slight that there is no way you'd feel them.
See Physics would have no problem with the existence of an infinite plane filled entirely with water.
It certainly wouldn't create a black hole because as has been repeatedly stated, there is no center of gravity, every water molecule is being pulled in every direction perfectly equally. If the plane of water were not infinite, and it was big enough, yes there would be horrible crushing and eventually a black hole. But since it is infinite, there is no center for all the water to be pulled to, and no "outside" from which you can observe light not escaping the plane.

You're right that there would be no light though.

What about solid ice planetoids suspended in wetspace?

Light and warm water "solar wind" currents coming from "stars" that are masses of incandescent steam?

It expands into similar space as our space expands into.

True but the mass, in this case, is infinite and dispersed evenly in all directions. Furthermore, the fact that the mass is all liquid means it is all of nearly uniform density, meaning that there will never be points where matter will coalesce. This means that there will never be a center of gravity. There will never be "down". Each molecule will experiance the same pull of gravity exerted by every other molecule in every direction. If that gravity tries to pull two molecules together than the electrons from each molecule will repel them.

You're a chump, user. Go back and read a book.

the elemental plane of fire isn't only fire, just like the elemental plane of water wouldn't be only water. there would a be a bottom and a surface

if your plane of water is only water then you have to make your plane of fire only fire which is stupid

The elemental plane of fire is the sun. Its fire on fire, and only fire.

Technically the sun isn't fire the same way burning wood is fire.

Elemental fire is a pretty dumb idea if it's restricted to the sort of fire created by wood burning, because if we're being really technical, that's different to phosphorous burning, which is different to gunpowder burning, and so on. I mean sure, you can restrict fire to be only carbon-based exothermic reactions, but why would you? Why not have elemental fire refer to all exothermic processes?

Speaking of which, a total, eternal plane of elemental fire doesn't work with our physics.

what if its the garbage burner of all the other planes, constantly being fed by portals?

or, what if its the garbage burner of all the planes, and when anything burns on another plane, it really makes a portal to the elemental plane of fire

Of course it doesn't work with our physics, it's a different fucking plane, in a setting with such bullshit as immovable rods which make no sense when applied to earth rotation.

The point I was making is that, in contrast to the elemental plane of water, which is perfectly compatible with our physics, an elemental plane of fire in the same style wouldn't work, at least not with conventional combustion. It could potentially work with nuclear combustion, but honestly I don't know enough about nuclear physics to say.

maybe instead of a place in the traditional sense its more like a time, the big bang, when the whole universe literally was energy.

>implying malevolent gravity wouldn't just remove itself from you so completely you'd fall apart
or black hole you

You're held together by electrostatic forces, not gravity. If only gravity was holding you together (the weakest fundamental force in the universe by the way), you'd be a mush on the ground right now in the face of the earth's vastly greater mass.

Yeah, I know about Strong Nuclear Force but I assume malevolent gravity would probably do something. An active weak force could beat a passive strong one after all

I'm going to need a citation that physics acts the same in a different plane of existence.

>the planes exist on dimensions incomprehensible to mortals
>incomprehensible to mortals

So how are you expecting your explanations on science that holds true in this dimension to apply to another?

It's magic, you idiot.

In old school manual of the planes it does mention players needing magic to survive the crushing depths of the sea but most people just wave that rule away. Kinda like how almost every trip to the plane of infinite air you manage to find a rare as fuck island, made of the plane's opposite element, just so it's easier to make maps and not deal with 360 degree combat rules.

In the end it's up to you if you care about these things but do whatever you think will have the most fun.

>god your fucking stupid

Says the guy who hasn't mastered basic literacy.

I mean, you're right, that other guy was wrong, but you aren't helping here. Go learn to english.

No gravity. No pressure. Learn basic physics before you try to use in something.

Fucking pathetic.

And no, subjective directional gravity isn't real gravity. It doesn't work like it. Therefore it can't increase pressure.