Well Cred Forums?

You ignore relativity. You can either view this from the perspective that the portal is moving or the entire universe including the cube are moving upwards. So the cube is moving depending on which perspective you look at it from.

I'm thinking b, because even though the cube is currently at rest, when the portal slams over it, i t is effectively moving through whatever length there is in the dimension between the orange and blue portal. That momentum isn't going to just vanish when it comes out the other side. There's kinetic energy invested in the cube at that point that has to play out.

Let me try it this way: It's like the cube is currently on a treadmill that is turned off. The cube is at rest. But when you turn the treadmill on and the resting cube runs out of platform to sit on, it doesn't just casually plop off the edge. It is ejected from the edge with an equal force as the treadmill was running at, minus frictions and other such things. The cube IS moving through that dimensional boundary. It must come out with an equal force.

Moving relative to what? The player puts a portal on the Moon, you telling me that isn't moving totally different relative to the portal on the Earth?

Option A

This. It's A.

My thoughts are still influenced by the game mechanics itself, I'm sorry if I ignored that. The object/area of the portals are under the effect of BOTH portals. as seen here(massive spoilers if you hadn't played Portal 2 btw). The portals do not care about the momentum of themselves, they only carry the momentum of the objects they carry. If the object wasn't under any momentum to begin with, then the it will just plop out. The slamming piston never actually touches the cube or exerts any force on it so it wouldn't move.

youtu.be/hHPwmzbpaAU?t=357
(massive spoilers if you hadn't played Portal 2 btw)

Attached: download.gif (550x400, 105K)

I dropped a hola-hoop over my body once. When it hit the ground, I accelerated upwards at nearly 9m s^2 Because somehow the momentum of the hoop was instantly transferred to me when it stopped.

You can't put portals on moving objects.

why?

wrong

Are you saying that if the pedestal holding the cube is small enough to also go through the portal then it would be option B?

I think since portals don't exist in the real world we can't prove that a force wouldn't be exerted onto an object proportional to the speed at which it passes through a portal. I really like your example more than any other though and gives great justification to A.

No. That is not what I said at all. Are you completely illiterate? I literally said that it is clearly answer A. I said absolutely nothing regarding the size of the cube.

The only way that your stupidity may be rectified is if you're a cute femboy. Otherwise your ignorance is grotesque.

This again.
The answer is B, it cannot be A. Its not even a question of physics we don't even have to go there, geometrically it cannot be A.

As the yellow portal moves over the cube, at each instant of time a sliver of the cube enters the yellow portal and leaves the blue portal. Each slice of the cube moves out of the blue portal as the next slice follows behind. Once the entirety of the cube has emerged from the blue portal it carries on moving, why would it suddenly stop, it has already left the influence of the portal.

The energy is transfered as the cube exits on the blue portal. So the answer is B you morons.

I didnt say anything about the size of the cube either. I said the pedestal holding the cube.

No. That is not what I was saying either. Your lack of commas and periods make your sentences hard to read.

Ouch.
Portal fags btfo.
>because planet earth is in constant motion to start with.

Both are correct. So, if given A or B, then the answer is yes

B - the force of the portal's momentum is transferred to the cube

The momentum of the portal is stopped by the pedestal.

Think about the revers, what if you threw the cube through the non-moving portal at the speed that the moving portal is moving?

Attached: portal.webm (356x200, 182K)

The cube is not being moved, the area around the cube is being moved.
If you take a box and put it down over the cube at a high speed, the cube is technically entering the box at high speed, if you stop the box half way, the cube does not suddenly spring upwards into the box.

Energy is needed for movement, energy can only be transferred, not created or destroyed.

When the portal is brought down over the cube, the cube is not suddenly given a jolt of energy that causes it to move.

This is video game physics. We're talking about real life

thank you

Attached: Screenshot_20181203-233152_Google.jpg (1432x1445, 554K)

A

The cube is only moving from our viewpoint though. If you started with the yellow portal 33% covering the cube, you have to ask yourself how is gravity affecting the two separate sections of box. Is gravity affecting the 66% box still on the platform as if it were just the 66% of the cube, if it were 100% of the cube, or potentially some mathematical function of both of those values? Hard to tell because portals don't exist.

Jesus fucking christ. It is like you and every other person in this god damn thread does not understand relativity. The fucking cube is moving depending on the frame of reference.

Why are you so fucking dumb?

neat

...no, I've actually done this. It just plops down

If I'm sitting in a moving train, a tree seems to be going by at 70 mph

If the train stops on a dime, does the tree fly off into the sky, because from my point of view, it was moving at 70+mph

Is that why it's using Portal's color scheme?

But hey, I'll bite. IRL, there are no Portals. No solution exists.

Depends on the version of engine.

In Portal 1 the portal disappears as soon as the platform moves.

In Portal 2 the engine freaks out:

youtube.com/watch?v=S85nudR6D-Y

if you said b your moms a hoe

I feel like saying it's B is kind of like saying that if you jump while running quickly on a treadmill you'll just fly off

"The cube is on a treadmill"
Energy is being transferred from the treadmill to the cube in the form of motion.

The cube in the example is not on a moving platform, the portal is moving.

Energy is not being transferred to the cube in the form of movement.

So from the frame of reference within the train not only is the tree moving towards the train but so is the entire universe. When the train stops the entire universe also stops moving towards the train. So no, the tree doesnt fly anywhere. It stops moving due to there no longer being a forced on the train moving the train or vice versa there is no longer a force on the rest of the universe.

Ah good you're still here. That's not how relativity fucking works at all

>But hey, I'll bite. IRL, there are no Portals. No solution exists.

Yeah it's a hypothetical. We're trying to say what if portals did exist, then how would it work? You can't test that in Gary's Mod

Correct

But that tree wasn't in two locations in space at one time, B fags arent arguing your logic, they are arguing that an object must be moving if it enters one portal and exits the other, regardless of whether the portal created that motion or the object did.

Imagine this. You are looking down the blue portal. You would see a cube moving closer and closer to the blue portal and eventually exit with the same speed as it was moving towards you as you were looking at it. It's that fucking simple. Now go study or something.

A.

retard

You ever see that mythbusters episode where they drove a car into a semi while going 60 mph?

It plops. The portal has momentum, the cube doesnt. So it cant fly out of it. All it does is just teleports faster than it would if the piston was moving slower.. fagots

reddit.com/r/Destiny/comments/4srd0o/a_brief_writeup_of_the_portal_problem_a/?utm_source=amp&utm_medium=&utm_content=post_body

Tldr; Result B breaks physics less than result A

The effect of gravity is pretty much irrelevant to this problem. Even if we take gravity into account it will not have an effect significant enough to flip the outcome, gravity is a weak force and the plunger is moving at speed.

How portals effect gravity is unspecified but it would be a major headache to come up with some rules for that, it would be best to have portals only effect matter.

I consider a portal to effect only the matter crossing its boundary, it does not operate on entire objects it works on an atom by atom basis. Any part of an object not actively crossing the portal will behave as per normal physics. A single object will behave the same as a stack of objects.

Portals can only exist (in reality) in the same orientation and opposite directions so that objects travelling through them have a constant direction of travel. Imagine you are in space and there is a companion cube next to you. You push the cube away imparting 1 joule of kinetic energy. You travel in the opposite direction and effectively have -1 joules of energy relative to the cube. The energy in this situation has been conserved. If a portal exists that can reverse your direction of travel then your -1 joules becomes +1 joules. You have gained 1 joule of energy in this circumstance for free violating the laws of thermodynamics. Therefore portals can exist and move but only if the direction of objects travelling through them is conserved and the portals do not move relative to each other.
One other important thing to mention is that technically the can not exist at all. Gravitational potential energy is given as a result of height and a portal allows you to change the height of an abject at will giving you free reign to create and destroy energy. Thermodynamics is displeased again.

I agree with you that specifically gravity is irrelevant. But if we did this in 0G then all that changes is option b becomes moving infinitely at the same momentum.

But thinking about the vectors of gravity would allow us to comprehend any and all changes in momentum from the cube

the earth and all its components are moving objects

Literally is how it works. You do not understand physics. Go read a textbook.

The fact that anyone purports to have come to a physics-based conclusion given this is proof that a bunch of random on the internet do not understand physics.

Relativity is specifically only about how light will always appear to go the same speed and nothing to do with literally anything else. (Except high end gravity curvatures) but that's it. It's not actually about thing being "relative" why don't you read the actual book?

The momentum the cube gains depends on the reference frame.
From the perspective of the cube no momentum is gained, if you had an accelerometer on the cube it would read zero.

So if I have the right angle that I look at it from I magically negate all of the moment you see and it doesn't move?

Considering how far off that is from the truth it is not worth engaging with you. You are in essence lying and pretending you understand physics but have not actually read books on physics.

Wait. Fuck me. I didn't read your full comment. I just say reference frame and got triggered. Sorry go about your day

There is a theory that the faults we see in others is just our own projected back at us

You could take a few minutes to download a standard textbook on physics and then just scroll down to the part talking about relativity.

Between A and B, I’d guess. While the top of the cube would be accelerated, the bottom of the cube Stil rest (accelerated with 1G to the bottom) and slow the whole cube down. So the Cube would fly, but not as fast as the platform with the portal moves.

Why would I do that when I physically have Einstein's book?

You see the moon bit in the game. Well, objects are seen in that instance, by the game's logic, to retain momentum relative to the portal. The game says it's B even if they can't actually exist.

Einstein wrote multiple books. Also whatever book you have by him you likely did not understand given what you've said so far.

Relativity says that all inertial frames of reference are equally valid. If you argue that A is the answer to this problem then you also say that there is an absolute reference frame in the universe that is more valid than other reference frames. And that violates the theory of relativity that you know so much about.

I mean relativity is about how light appears to go the same speed regardless of any observers reference frame. Do you disagree with that?

You're the one trying to invalidate certain reference frames to claim you're right in specific noninertial reference frames

If all reference frames will agree how is that different than there being a universal one?

A no force on the cube is applied

It is about way more than that. Please just read a book.

Also what said.

At a glance, the relative velocity between the cube and the portal would sensibly determine how fast it moves out of the blue portal, but this is based on intuition from the game, which isn't reasonable since there aren't moving portals in the engine. Actually all the orange portal is doing is bringing the space in front of the blue portal to the cube, and so it probably wouldn't even plop, it would just slide or stick on the slope depending on the coefficient of static friction between it and the surface it's on.

People spend a lot of time telling me to read. And when I say only I mean that physical things that aren't light don't react that way because objects that have relativistic speeds will actually "lie" about their length and weight and location in the universe. And relativity as a theory has no bearing or caring on anything slower than a relativistic speed where Newtonian physics still work just fine

That was very difficult to follow given the numerous grammar mistakes. All that is being said to you is that there is no absolute reference frame so you cannot distinguish between an object moving and everything else moving towards that object. It is odd that you're this arrogant when you lack some of the most basics of physics.

"read a book"
"people spend a lot of time telling me to read"

Read a book on basketball because you just dunked yourself so fucking hard

Wouldn’t it have to be, B? The portal isn’t just coming down into the box; it’s coming down onto the box, platform, and beam. That distance alone should be enough force to push it outward into a forward momentum

TOP KEK

"Allllllllll reference frames agree."
So it doesn't matter where I'm standing in the room or if I'm on a bike or in a car or on a train. I see the companion cube not moving as it is swallowed by the portal and I see it continue to not move after it appears on the other side of the blue portal. Simple fucking physics

It’s like driving a tunnel over a car (if this were such a thing). It’s: A

Except from the reference from of the moving portals the cube and the rest of the universe are moving towards it.

Do you jack yourself off to being a retard online?

Eh. I could have worded that a lot better. But whatever. I forgot sarcasm literally doesn't read on the internet.

Cube has a high velocity relative to the orange portal, option b

They do in portal 2 but only during the part where you cut the neurotoxin lines w the laser

Not user - but there’s a difference between a portal and a vortex. If it were a vortex crashing down upon you, it would also be sucking you inward; thus, giving you momentum and ending up with B. However, the object in question is not in motion and we’re talking about a Portal (which is basically an open window). The answer is clearly A.

As user over here stated:

The orange portal is a noninertial reference frame. And if you can't understand sentence one of relativity how can you be so idiotically arrogant of the rest of it. It says that all reference frame agree. But you claim that all sensible real ones don't count because of one maybe two that you came up with? The cube is touching the platform. All that the cube knows or understands about any of this is that it's touching that platform and then gravity shifts on it. That's it. And if a reference frame disagrees with someone whose just standing there. That reference frame is probably wrong or misinterpreted

A.
/thread

The stupidity of people not understanding that the only portal that matters is the blue portal is giving me cancer. The answer is B. Stop being faggots.

Attached: tits.jpg (1280x720, 81K)

This. Only tards chose b

Yeah that was a thing that always bothered me. I saw it and said to myself "that moving portal seems odd for some reason" until I realized portals cannot move... Buttt... The earth is constantly moving throughout space soooo.... Idk Valve pls fix.

Attached: 1581662926938.jpg (1000x660, 99K)

This is they only true answer here.

I think it's less of "portals can't be on moving platforms" and more of a "portals can't be on unstable platforms", since we see in Portal 2 that you can place a portal on a moving surface

No bruv you can't, except that one scripted laser neuro toxin laser event (and that was scripted and the laser wasn't actually being rendered through the portal you shot.) The game engine overflows and crashes the object when you try.

Let's hope for real moving portals in Portal 3!

yea you're right, but i was talking more if portals were reall, and not in the game world.
Because, if you think about it, the only other times where there are walls you can portal and move, are when Wheatley is messing with the test chambers and smashing them together, causing the surface to shake and be unstable

The solution is easily B without any issues, moving portals are not a problem.

Where the problems really appear is accelerating portals. If the speed a portal is moving changes when something is halfway through, I am just not sure how exactly this will behave. I feel that there should be large forces upon the object at the boundary, probably resulting in serious damage to the object at the point where it crosses the boundary but I am not sure. It may not be possible to come up with a coherent model for this without being forced to specify exactly how the portal effects matter which crosses its boundary.

You're retarded.
If you throw say a ball into the portal it will shoot out like B
If the portal simply engulfs and standing still object the object will plop like A

A, mostly, with a small effect toward B. The cube is lying stationary, thus not subject to kinetic energy. As the platforms slam together, there would be a -slight- induction of energy to the cube, causing it to gain a small amount of momentum. The net effect, combined with the angle of the exit portal, would be that the cube jogs relative to the force of the impact, and it would give a small forward flip and skid down the angular surface.