I’m not sure speed of the molecules is sufficient, because speed is only related to temperature. What’s forcing the air out is pressure, which may not influence speed.
Yes, it’s not consistent in the game. This depends on how realistic you want the scenario to be.
My vary vague memory here - it has been decades since I read the book. In Larry Niven’s Ringworld he describes a storm created by the atmosphere leaking down a huge crater - with a hole at its bottom - that has been created by a meteor impact onto Ringworld. Earlier in the book the protagonists observe the crater from the other side of Ringworld as they approach. The point being the Niven, in typical hard SciFi, noted that this damage would take a very very long time to actually rain the atmosphere.
It amounts to the same thing. Fundamentally, all a gas is is a bunch of particles moving around and occasionally colliding with each other or with the boundaries of their enclosure (if any). Nothing can happen in a gas faster than the thermal speed, and speeds will in general be less because the individual molecules aren’t moving in exactly the direction you want.
I’m too lazy to check your math, but I hope you didn’t solve for zero, because we’d have to find a plug long before the atmosphere was completely gone. I’m guessing you’re off by an order of magnitude.
What about energy? Would wayward cosmic beams of X get sucked through the portal, bypassing Earth’s atmosphere, and create some sort of localized radiation zone?
The average speed refers to RMS, and doesn’t define a maximum. If what you said is true, why hasn’t the moon trapped an atmosphere?
The hole causing the eye-storm was small, but there was also the much much larger Fist-of-God hole, which Louis Wu observed was large enough to let all the air out of the Ringworld fairly quickly if it hadn’t been way up outside the atmosphere. And then in Ringworld’s Children an ARM ship has an antimatter containment failure and blows a huge hole in the Ringworld that requires an enormous fusion-powered torus to temporarily block the air from leaking out … and can you believe some people don’t like that book?!
OK, I should have said that nothing significant can happen at faster than the thermal speed. There will be a few outlier molecules that are significantly faster, but not enough to really matter on the macro scale. And just to be complete, I should also specify that I’m referring to neutral gases, not plasmas where magnetic effects can be significant and where most things happen at the Alfven speed.
Would this transdimensional ring start to spin if you let go of it? What would restrict it from achieving near speeds approaching the speed of light?
Portals of the sort in the game are impossible according to everything we know of science, so if they’re possible, then our knowledge of science is seriously flawed. Your questions cannot be answered without knowledge of that new physics, which is currently unavailable to us.
Occasionally? Only if 10 billion times per second is “occasionally.” Without frequent collisions, you can’t have the Magnus effect. Hell, airplanes wouldn’t fly otherwise!
Secondly, I think some of you are making a common mistake about Portal physics. If gravity were to pull you through a portal, there’s no reason to think it would pull you back in the other side. It would push you away from the exit portal. Think of it like this- if I had a floor and ceiling arrangement, and held and arrow facing down, and stuck it through the floor portal, where would it point when it came out the other side? Toward the floor, of course. That would be the gravity vector.
So saying “you’re not sucked back in” doesn’t prove or disprove whether forces are transmitted through portals. As far as I know, we still don’t know.
Thirdly, you don’t need to weld a pole together to get a self-sustaining rod. Just put a portal on the wall and one on the floor, such that they nearly intersect. Place a short rod through the hole, slanted toward the ceiling. It’ll come out of the floor portal pointing away from the wall. Then drop the rod. The part sticking out of the wall will drop toward the wall. The floor piece will slide toward the wall as well, eventually intersecting and holding itself up.
Really? I had no idea. Do hypothetical questions not exist either?
Nothing at all; this is pretty much what it would do. There’s no such thing as conservation of energy in the world of Portal (see below).
I wouldn’t say that it’s as bad as all that. You’re basically doing classical mechanics with a constant gravitational acceleration field, along with some identifications (in the topological sense) of the space you’re looking at. I will certainly grant that there’s no useful notion of conservation of energy or momentum in this world, but that doesn’t mean we can’t do basic things like compute trajectories.
See this trailer, at about 1:55. There’s a brief clip of a security turret oscillating between two portals in the floor. I don’t think this would be possible unless the gravitational force field on one side of the Portal was at least somewhat insulated from the other side. Plus, let’s be honest: this is a computer game, and the simplest way to get an effect like this (in terms of computational overhead) is to not have to deal with the effects of gravity leaking through portals. It’s probably hard enough to simulate the physics of this world without having to recalculate the gravity field every time you move a portal.
A gas can have frequent collisions, but it doesn’t need to: Almost any level of collisions at all is enough to behave as a gas. In particular, the mean free path of an air molecule between collisions with other air molecules is macroscopic, but a volume of air smaller than that still acts like a gas in every sense.
So in the “real” world (where portals are theoretically possible), would friction with the air create enough heat to superheat the metal bar until…what? Either the bar melts or the air around it explodes? Could you create a giant super generator by wrapping the bar in copper coil?
Yeah, I would guess that it would heat up, melt, and then possibly break apart due to the Plateau-Rayleigh instability. I don’t think you could make a generator out of this, though; the magnetic flux through your copper coil is going to always be the same, and you need a change in flux to create an EMF.
Any sort of portal which would be possible in the real world would have to obey conservation of energy, and so you wouldn’t get the accelerating bar to begin with. If you had a portal connecting the Earth and the Moon, for instance, there would have to be an extremely strong gravitational field in the vicinity of the portal, such that it would take just as much energy to pass through the portal as it would to reach the Moon through normal space.
My line of questioning picked up from applecider’s hypothetical question, which involved not a portal on Earth and a portal on the Moon, but rather a portal on the ceiling and a portal on the floor - thus a continuously falling pipe/bar that is continuously accelerating.
I think there’s some confusion here. In any world in which portals work as in the game, energy is not conserved. Or, equivalently, if energy is conserved, portals cannot work as they do in the game. A portal pair between the floor and ceiling violates conservation of energy just as much as a portal pair between the Earth and the Moon.
So by the “real world” in Post #35, did you mean “a world in which energy is conserved” or “a world in which portals work as in the game”? Because you can’t have both.
Same problem, though. An object (it doesn’t have to be a continuous bar) falling through the portal-loop would gain speed while it’s away from the portal, and lose speed while actually going through it, in a way that would balance out overall (except you’d still lose some additional energy from friction and the like). Effectively, you’d have a funny-shaped flywheel or pendulum, where at any given time some mass is going “up” and some is going “down”, or where the same mass alternates going “up” and “down”.