/sci/ - Science & Math

Doesn't exist in real life so it makes no difference which one you pick.

A.

>>4319877
http://en.wikipedia.org/wiki/Wormhole

>>4319861
A.
lrn2momentum

>>4319890
>wormhole is a hypothetical topological feature of spacetime that would be, fundamentally, a "shortcut" through spacetime
>wormhole is a hypothetical topological feature
> is a hypothetical topological
>hypothetical

>>4319898
Also,
>There is no observational evidence for wormholes

>>4319877
I wish I could help you understand just how wrong you are. Questions like this relate directly to concepts like spacial distortion and quantum mechanics. "Portal" may be fictional, but these concepts are very real.

>>4319898

Hypothetical does not always mean not real.

In this case, it means not yet observed.

>>4319904
Following your logic, you could also argue how magic works in harry potter. Why don't we start doing that too?

>>4319898
>>4319898
>hypothetical=unscientific
>implying hypotheses are unscientific

>>4319918
>implying i ever said they were unscientific

Alright, alright, in the spirit of avoiding a terribly drawn-out and boring semantic battle, you would need to know what forces were at work within the portal, etc., etc.
Because it's hypothetical, and all the physics haven't been worked out, you can't know (but it would probably be A).

ITT: more A-faggots

>>4319914
>you could also argue how magic works in harry potter
As soon as I see voldemort rising from the dead, I'll hop right on that shit.

In the mean time, though, I'll concern myself with quantum entanglement and the conservation of momentum.

A

CoM. Is this that hard?

/v/ had this thread but they know jack shit about physics.

Lets pretend the portal system is a hula hoop
Lets pretend the block is floating in space
Lets pretend there is no gravity

Still following me?

Ok, the hula hoop drops down and passes the block at a constant speed.

The speed of the block relative to the hula hoop is the same before and after

look at the problem from the hula hoop's reference frame

block goes out at the same speed as it goes in


therefor it doesnt matter if the portal is moving or the block is moving

>>4319940
>I'll concern myself with quantum entanglement and the conservation of momentum.
>by discussing a video game
We've got a real scientist right here.

A, as always.

"You appear to understand how a portal affects forward momentum, or to be more precise, how it does not."
-Glados

>>4319946
conservation of momentum means the entire system bro, portal and block

>>4319898

What about Tesla's so called wall of light?

>>4319953
Did she also mention how you can't put portals on moving surfaces?

Definitely A, because the cube isn't moving; the world around it is (I think?) metaphysics are very confusing. Also, I like your use of Portal. You could've used some boring description.

>>4319948
You throw a ball through a hula hoop, it goes in at some momentum and comes out with the same momentum.

You put a ball on the ground and drop a hula hoop on top of it. The hula hoop drops to the ground over and around the ball but the ball doesn't come shooting out.

Therefore, A.

Someone just go on portal and test this shit out.

That's the only way we can get the truth

>>4319861
A. 100%

First, consider the idea of a tall cylinder instead of just a tiny cube. The cylinder emerges from the blue portal at the same speed as it enters the yellow one, otherwise the shape would be distorted.

Second, consider the consequences of the yellow portal as just a circular hole. When it slams into the pylon holding the cube, the cube itself will be free of any forces acting on it other than gravity, meanwhile the pylon will be struck with the force of the high speed piston and accelerate downward.


The picture acts on our perception of the result of the pylon holding the cube impacting the yellow portal. The abrupt stop relative to the portal gives the impression that the cube should shoot off into the distance due to the relative nature of movement. However, we must not forget that the cube's momentum change is relative to the pylon. The moment after the yellow portal gobbles the cube, the pylon accelerates downward rapidly(assuming it is weaker than the piston), thus preserving momentum between it and the cube with respect to the relative acceleration of the yellow portal.

The point to remember is not to confuse momentum with relative motion.

>>4319956
No, not in Portal 1. Haven't finished 2.

>implying the ball had any momentum to begin with
>implying the portal machine didn't have all the momentum
>implying when the portal machine stopped on the cube, it transferred any momentum to it
>implying all of its momentum wasn't lost in the collision to the platform below

Its A.

>>4319956
Also, http://theportalwiki.com/wiki/GLaDOS_voice_lines

>>4319954

Several examples have been given using the entire system, bra.

Friendly reminder from /v/ that the one known rule is "speedy thing goes in, speedy thing gets out".

This should solve it for anyone who knows what relative velocity is.

>implying a portal or wormhole can be moved

think about it, yo

>>4319962
cant put portals on moving surface, if you hack it in you will get undefined behavior
>>4319972
Theres a moment in portal two where the surface you put a portal on moves, the portal is destroyed

I don't care if glados mentioned it or not, its not possible in the game


>>4319958
lets say the hoop falls at a constant 1 m/s

the speed of the hoop relative to the ball is 1m/s before it starts going in.

Right before the hoop hits the ground, the block is traveling at 1m/s relative to the hoop, and is pretty much out the other side

>>4319958
>not understanding how your own analogy works
Therefore B.

>>4319989
>the block is traveling at 1m/s relative to the hoop
Yeah but look at the figure. The perspective is not of the hulahoop but the observer is outside.
If you were on the hula hoop's surface (somehow) it would seem the ball was shooting out but you're observing the system from outside.

>>4319955
We call those "sparks"

He was just conducting his high frequency tesla coil through himself

>>4319999
>not actually explaining why the analogy is wrong
Therefore, its A.

>>4319980
>speedy thing goes in, speedy thing gets out
>from the observer's point of view, cube has no speed going in
>from the observer's point of view, cube will have no speed coming out

What now?

But wouldn't relativity hold, so since the cube is moving relative to both portals (When looking through B, and not at it) wouldn't the cube keep its relative momentum?

>>4320021
Its still wrong.

>>4320020
>>4320020
>>4320020
>>4320020

/discussion

Is this thread a troll?
Frames of reference; they're real! The physics has to be consistent in any frame of reference. If our frame of reference is that of the portal, the object passes through "us" with a constant velocity.

>>4320021

Mind is blown.

So can i get a larger image where you read the writing?

>>4320039
>physics has to be consistent in any frame of reference
Just because something is moving to one observer and appears still to another observer doesn't mean the physics is inconsistent.

>>4320020
>>4320020

From the observers point of view, the cube has momentum towards the goddamn portal. The portal is moving.

>>4320060
From the observer's point of view, cube has no momentum. Its sitting still in the platform. You can even see it in the fucking picture.
From the portal's point of view, the cube has an "upward momentum" towards the portal.

>>4320067

Yes, and it's the momentum from the portals point of view that DEFINES how it will come out. The observer STILL observes that the cube MOVES towards the portal in the portals frame of reference.

>>4320084
>observer STILL observes that the cube MOVES towards the portal in the portals frame of reference
>observer observers in the portals frame of reference

Your logic has some serious faults.

portals are like doorways.

no matter how fast you move a doorway, it will not affect the things going through it.

OMG.

People. Portals cannot be moved once placed. Well established in the games. A moving portal is IMPOSSIBLE.

Neither A nor B.

>My face when /v/ thinks B is the right answer

>>4320087

That's not what I've said.

You can just stop posting/admit you're wrong.

>>4320097
>That's not what I've said.
Those are the exact words from your post, you moron. Read it again.

>>4320064
>mfw someone finally gets it

>>4320090
But from the POV of the doorway, the object IS moving faster out of it if you move the doorway.

Therefore B.

Seriously, lrn2referenceframes.

Reading all the A answers is like that stuff with the pen not dropping on the moon. And about as disappointing, considering this is supposed to be /sci/.

>>4320067
The portal is a device which allows us to change our frame of reference. Imagine looking at an orange and a blue portal, both situated in front of you. Throw an object into the portal and it loses no momentum, but it comes out of the blue portal with momentum OPPOSITE its original momentum. Normally, this is impossible, unless the object received momentum from another object (such as the wall). But the thing is, when the object entered/exited the portal, the frame of reference was changed. If we made our frame of reference consistent with the object, then we would notice how the object's momentum wasn't changed at all. That is the case for stationary portals.
The logic should be CONSISTENT with any case, which is why this problem is provocative.

Since the portal "changes" our frame of reference, it is difficult to see what is actually happening. Let's use the portal's frame of reference instead. In the static example, the portal's frame of reference is both "facing toward the object's origin" and "facing away from the object's origin." In that case, the object continues to travel in the same direction the whole time. If the portal is moving, then our frame of reference is simultaneously "moving toward the pedestal" and "facing toward nothing." The object is consistently moving toward/away from us (remember, the portal forces us to adopt a dualistic reference frame where negative and positive momentum with respect to the portal are equivalent). The object had some non-zero negative momentum when it was traveling toward the orange portal, so it MUST have a POSITIVE momentum with EQUIVALENT magnitude as it exits the blue portal.

>>4320021
The movement seen by on the other side is an illusion.

Think about it as a platform lowing with a hole in the middle.The pillar with a box on it isn't moving but the platform is.

The movement is an illusion by on your perspective, when you reach the bottom the box isn't going to suddenly accelerate.

>>4319986
>>4320093

winners

>Go on /v/, find this thread, everyone says it's B
>Go on /sci/, same thread pops up, everyone says it's A
No surprise there /v/ is dumb as a fucking brick.

>>4320102

I said that the observer can affirm that the cube has momentum in the frame of the portal it will go in.

By the way, your definition of "exact" is off.

>irony

>>4320110
It isn't suddenly accelerating, it is just NOT decelerating!
The platform stops dead (generating a large impulse), but the block doesn't receive any force to cause it to undergo a large negative acceleration (which is necessary to stop a moving object from moving). The box "pops" upward just like a hacky-sac in your hand flies upward when you jerk your hand up.

>>4320106

No man, they couldn't know the rules made by valve. The ones that did know are disappointing though.

>>4320106
Oh look it's the reference troll, implying forced gets applied to the cube from the portal instead of the ground underneath the cube.

>>4320120

>The platform stops dead (generating a large impulse)

This is wrong.

According to the reference frame of the box, it hasn't moved at all.

It's just an illusion of movement from our own perspective.

>>4320120
It was not accelerating in the first place.

It appeared to be moving because of your perspective but it's actually stationary and so are you.

>>4320111
>actually thinks there are no moving portals
>why can't you hold all this newfag?

http://www.youtube.com/watch?v=WZMzJvGmylQ

>>4320133
Acceleration and velocity aren't the same thing! I can't believe I have to explain this!

Game portals are iffy, because they don't let gravity through them.

There is no clear answer.

>>4320136
That's not the issue and you're wrong.

The object isn't moving, it appears to be moving because the portal makes them closer in space. The object isn't accelerating or decelerating because the portal doesn't effect the momentum of the object.

>>4320141

Assume we work in a frictionless gravity-less environment. Yes, the cube is resting on the platform even without gravity.

>>4320148
The portal doesn't effect the momentum of the object *relative to the portal's frame of reference.* If the portal is moving, everything that isn't moving along with the portal has non-zero momentum.

If both portals are stationary, there's nothing to worry about and the momentum's magnitude doesn't change (the direction is almost always changed, of course). If one of the portals is moving relative to the other, then you must calculate the before and after momenta relative to the orange and blue portals respectively.

>>4320136
><span class="math">\displaystyle \vec{F}_{dim} = \Sigma F_{dim} = m\frac{d\vec{v}}{dt}[/spoiler]
>mfw

>>4320159
>greentexting LaTeX

>>4320150

I mean, if gravity it's not passing through, then portals aren't a fold in our dimension (wormhole) and then we're dealing with some sort of materializer.

Now I'm curious.

If you have the yellow portal accelerating downward through a bunch of air molecules, doesn't this cause molecules to exit the blue portal? If so, at what magnitude of velocity are they moving at?

>>4320164
>greentexting

>>4320169
Don't do this, nigga. Just don't.

>>4320113
>thinking A is true
I think I'm going to /v/, since there's apparently a higher fraction of smart people there.

Next statement is assuming we use the situation in which the orange portal piston doesn't stop suddenly.

So say you're watching the blue portal. A cube suddenly pops out of it. It passed through the portal at 20m/s. According to people answering A, its just going to seem to move 20m/s as it appears through the portal, then suddenly stop dead in its tracks defying any momentum it would have had while moving through the stationary blue portal?

>>4320157
Except you don't because of the one time exemption that the portal entails.

The portal connects to places in space when something travels into the portal it's as if nothing happens.

Like a hula-hoop that is magically connected to a hula-hoop on the moon. From the moon it would appear you're moving up, for you it would appear the moon is coming down around you. So when the hula-hoop hits the ground and you're on the moon it will appear as if you were shooting up through the other hula-hoop and then suddenly stopped and from your perspective it will appear that the moon fell down around you and suddenly stopped but in fact neither of you moved.

Tilting the hula-hoop would make the moon appear to shift but it's not going to making everything fall to one side or the other.

>>4320113

/v/ is partial to the letter b aren't they?

I'm from /v/ and I'd say A.

>>4320134

There are no moving portals in the way the OP's pic described it.

>>4320175
>deriding greentext with greentext
>post "kill everyone in this thread" when you're in this thread

You sure are smart, bro.

Well, I built a quick mod and A happened. Since the game designers are the ones in charge of physics and such, I'll assume this answers everyone's questions?

>>4320218
Empiric proof, fucker

>>4320218
I also build another mod where two crushing platforms both have portal-able surfaces. Results show that you can indeed get crushed between 2 portals, in case anyone was wondering.

>>4320214
>pedantry

>>4320217
>implying mockery
>implying poster doesn't also want to die with the thread participants

You sure aren't smart, bra.

guys the portal will never reach it because it only moves half the distance at a time just like a limit it will never get close enough to it so the box won't go through it ever.. it's like an analogy for life, it's fucking beautiful

In real life or in the game? If in real life, I think >>4320218 answered it. In real life, this would cause so many problems with physics Newton would come back to beat you.

>>4320229
You should put the results up on youtube. 100+ thousand views easy.

Why doesn't someone just fucking build a model in Graay's mod already? These threads are starting to aggravate me.

>>4319908
in other words, not observed

>>4320265
do you have to observe something for it to exist?

>tree in forest etc

Portals can't move because they are the same point connected in space (fuck you, that part with the moving platforms in the neurotoxin chamber never happened).

Since they are the same point, there is no stored velocity between the two points. A happens.

>>4320272
>do you have to observe something for it to exist?
In fact, you do.

Observation is the only empirical method of testing existence. Without it you might as well believe in God.

>>4320298

Go fuck yourself. No one thinks you're more of a scientific rational thinker when they hear you say shit like this on here just that you're ignorant and a try-hard.

>>4320306

>>4320306
 

>>4320306
  

>>4320306
   

>>4320313
>>4320321
>>4320327
>>4320332

Same butthurt fag.

>>4320342
Same mad fag.

>>4320298

Nice to know that subatomical particles did not exist until we observed them.

>>4320352
Implying they aren't indirectly observed by the processes they execute in our daily lives.

discovery =/= observation

>>4320352
>equating imaginary beings with subatomic particles
Though we did not observe the particles themselves, their influence is seen and felt all the time.

>>4320345

More like different, unamused fag.

>>4320360
Haha, you called yourself a fag. What a faggot.

>>4320356

So, according to you, if the human race was blind, light would not exist?

>>4320365
No, because other things would still react to light, and humans would observe those interactions.

I'm sorry you're not a genius like me who has completely understood rational empiricism. Why don't you go try the kiddie table: >>>/b/

>>4320365
It would still have influence, so your post is redundant.
If you didn't understand what influence means, you need to go back to elementary school.

>>4320362

That's because I suck dick.

Now stfu and stop quadruple posting.

ITT people who don't understand Godel

>>4320368

So, again, if, for whatever reason, (For example, lack of proper tools) we were unable to observe said interactions, would the things causing them simply not exist?

No.

Going back to understanding the portal concept better, the whole thing makes me think of the conservation of energy. If the cube was not moving, it had 0 kinetic energy... so my understanding is that unless the portal acted on it in some way, it could not develop any more energy. So, A

You cannot conserve momentum across multiple reference frames

fuck off

>>4320430
No, faggot.

Either they are observable, or they don't exist. Nothing that exists cannot be observed.

Jesus, how are you so fucking retarded, and even worse, so cocksure about it.

>>4320535

>Discussing complex metaphysics/philosophy

>HUURR YR RETARDED U DONT UNDERSTAND HURRR

Wow. I don't normally come here, I was linked from the /v/ thread, but you guys are fucking elitist assholes.

>>4320545
>from /v/

Sorry, we're on a higher intellectual level than you, if you can't keep up maybe you should just stay on /v/.

>Why don't you have a girlfriend?

I'm sure that's a question much more suited to your mental capabilities.

>>4320535
>Either they are observable, or they don't exist. Nothing that exists cannot be observed
Different anon here, but it sounds to me like you're describing a human dilemma rather than a dilemma of reality.

Unless that's what you're trying to go for.

>>4320545
Not all of us.

Just a good portion of us. To be fair, though, what kind of people did you expect to show up in a thread titled ">Guaranteedreplies.jpg"?

>>4320555
Jesus Christ, did reddit go down or something?

This is isn't fucking rocket science.

Relative velocities between the platform and the block. Its B.

>>4320555

That something is observable does not mean it will be observed.

>>4320565
Look, man.

You're encroaching on a topic that delves heavily into semantics. It's a lethal combination of both confusion and pointlessness.

Not only is it the stupidest thing to argue about, it's one of the most worthless things to argue about. If people are not able to understand your argument, it's because you haven't formatted it in a way that they can understand and that it's literally offensive to logic.

I ain't saying that you're wrong. But I will say you are acting like a manchild with how you're handling this discussion. So why don't you just chill out for a bit and try convincing people instead of demanding they see things your way?

>>4320535
>>4320535

>Nothing that exists cannot be observed.

http://en.wikipedia.org/wiki/Observable_universe#The_universe_versus_the_observable_universe

What now?

>>4320568
That's not how relativity works.

Relativity is a concept that must be applied to the entire system, not just certain parts of it. You've left out the relative velocity of the block in comparison with the blue portal.

>>4320583
But the velocity between the orange portal and the cube, ie the velocity with which the cube enters the portal is non zero.

>>4320580
Yes, and how do we know the difference between the observable universe and the rest of the universe? Because the portion outside of the universe has interacted in some way with things in the observable universe. The distinction is only useful to show that we can't /see/ the other portion.

Either /sci/ is a lot dumber than I thought, or we're getting an influx of plebeians onto our board.

>>4320579
Not once did I demand anyone do anything. Although, I would enjoyed it if you stopped acting like a massive faggot or leave this board immediately.

>>4320585
and thus the velocity with which it exits is zero as well.

>>4320585
But the velocity must be maintained both before and after exiting the portal.

Unless the portal were to maintain constant velocity, the cube must stop when the portal stops. If the orange portal has stopped yet the cube keeps moving, this means that you didn't maintain your frame of reference.

>>4320586
http://en.wikipedia.org/wiki/Gödel's_incompleteness_theorems.

>>4320598
unless the the orange portal stops only when the cube is all the way through.

>>4320580
The irony of your argument is interesting too, and it goes back to my first post. If you think things can exist that can't be observed, then why don't you believe in God?

>>4320602
I haven't read a single other post in this thread, but I can assure you that your reference to Godel's theorems is irrelevant and you don't actually understand them.

>>4320609
Again, that's not how relativity works.

Relativity means that you choose a frame of reference and you stick with it. If you choose to make the orange portal that frame of reference, then the cube must *always* be be going a speed relative to the orange portal unless acted upon by another force.

This means that once the orange portal stops moving, the cube stops moving.

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>>4320602
See: >>4320623

I'm glad someone on /sci/ isn't a complete retard.

If there is not proof of something, it remains an unknown.

Asserting whether something exists or not without proof is equally pedantic and stupid.

ITT: everyone mad.

>>4320662
Take a look at >>4320642 for 3 seconds and tell me that he's going to listen to anything anyone has to say at this point.

Quit poking a hornets nest.

Option C.

Shit like this is why wormholes are unphysical.

>>4319914
http://www.fanfiction.net/s/5782108/1/Harry_Potter_and_the_Methods_of_Rationality

>>4319948
If the blue and orange ends of the portal are moving relative to each other, I don't think we can count it as the same frame of reference?

>>4320680
I only listen to people who agree with me. If you're even slightly intelligent, you would agree with me.

>>4320712
Good for you.

Now go buy yourself an icecream cone or something. You clearly deserve it.

Just imagine that instead of the cube, you were standing there. When the orange portal falls onto you, would you go flying upwards? Of course this is from only one frame of reference, but for portals I would assume that reference would always be from the object passing through the portal.

>>4320726
DOUBLE SCOOP, MOTHER FUCKER!

I wrote this for the /v/ thread, can someone tell me if I made any mistakes?

Four variables, portal A velocity, portal B velocity, cube before C1 velocity, cube after C2 velocity:

A) Stationary portals, moving cube
A = 0, B = 0, C1 = 10, C2 = 10, TOTAL = 20
As the cube moves through the portals, A moves -10 relative to the cube, B moves -10 relative to the cube
The cube enters and exits at 10
A + B = -20
C1 + C2 = 20
(A + B) + (C1 + C2) = -20 + 20 = 0

B) Moving portals, stationary cube
A = 10, B = 10, C1 = 0, C2 = 0, TOTAL = 20
The cube moves -10 relative to A, the cube moves -10 relative to B
A + B = 20
C1 + C2 = -20
(A + B) + (C1 + C2) = 20 - 20 = 0

C) One portal moving, one portal stationary, stationary cube
A = 10, B = 0, C1 = 0
The cube moves -10 relative to A, the cube moves -10 relative to B
A + B = 10
C1 + C2 = -20
10 - 20 = -10
Therefore C2 = -10

posted this in the /v/ thread.

Obviously the block comes out of the portal the same speed as the rate the portal moves, but the solid of the plate it rests on absorbs the energy. We cannot just make energy, therefore A.

>>4320743
lol, didn't read

>>4320298
If fire a photon / other particle out of my future light cone, I will never encounter or hear from it again, but inferring that it has disappeared is to posit an *extra* process which must happen. occam's razor, bitch

GUISE GUISE. The "Portal's Frame of Reference" keeps being mentioned. Can we prove something to the effect that the ends of a portal can't be in relative motion to each other (I know GlaDos said pretty much this, but if we can derive it we win the internet).

Corollory: if we prove this, can we use it to measure and confirm, for the first time, the one-way (as opposed to round-trip) speed of light, and therefore the isotropy of spacetime?

>>4320743
You made the mistake of providing 4 different velocities.

There are only 3 objects, depending on how you want to analyze the scenario. Either the cube can be analyzed as having two separate velocities, or the portals can be analyzed as having two separate velocities.

Keep in mind that even though they are in separate locations, both Portal A and Portal B are the same portal. The fact that they exist in different spots and appear to have different velocities is merely a manipulation of space.

It's better to leave out calculations in this problem. Adding numbers will only serve to overcomplicate it.

>>4320765

The funny thing is, if the platform the cube was sitting was pushed up really fast and collided into the upper platform, the cube would do 'B'.

>>4320774
Well C1 is the cube's speed as it goes through A and C2 is the cube's speed as it goes through B.

I was working on the basis that C1 relative to A has to be the same as C2 relative to B, so if C1 is 0, A is 10 and B is 0, C2 has to be -10.

But since you're saying that both portals are the same thing, does that mean that A and B can't be different?

If you can't solve general relavitity problems and can't manipulate a wormhole metric then you can't speak with any authority on this problem.

If you aren't talking about general relativity based wormholes as portals then you are just making up your own personal model of portals and arguing with other people's personally formulated models of portals.

You're free to engage in this mental masturbation. But, you aren't free to apply classical mechanics to a mechanic in a puzzle game and argue it with the self righteousness that implies you are speaking in any way authoritatively.

>>4320765
tentative:

1. Suppose the pedestal on the left in the picture is fixed to frame of reference K, with the orange portal's frame of reference K' moving relative to it.

2. Suppose blue portal A is also fixed to frame of reference K.

3. In the block's frame of reference K, it is (by definition) at rest. As the portal comes down around it, no force has been applied to it, save for the sideways pull of gravity. As such, its ownly deviation in motion from the (also at rest) pedestal is to fall sideways with acceleration 9.81 m/s^2.

4. In the Blue portal's frame of reference K, the block and pendulum are in constant motion with velocity v. As the pedestal is hit by the orange portal, a force is applied to it, and it stops; no such force is applied to the block, and its only deviation from constant motion v is to accelerate sideways at 9.81 ms^2.

5. The relative speed between the pedestal and the block at the moment of impact is both 0 and v, where v =/= 0. But this is an absurdity.

6. Either 1 or 2 must be false

>>4320798
Yes and no. It depends on the approach.

If you treat the cube as being stationary, then you can treat A and B as being separate.

But if you choose either portal as being stationary, the other one must be "stationary" as well. I know it sounds really odd, but don't think of the portals as "moving" the cube from point A to point B. The action is closer to "bending" it from point A to point B.

Though the cube is changing its location, its velocity remains the same and has never actually "moved". Portals simply have the ability to turn point A into point B, but nothing more. I'm not sure if this explanation was any clearer, but I hope it helps.

>>4320820
tl;dr

Points A and B look different, but portals inherently function by combining the two areas into a single location.

It's like a warped version of "entanglement".

>>4320828
>>4320820
This makes more sense to me.

So basically, the answer is dependant on whether these fictional portals are meant actually be moving the object or work in the way you both described. But they're fictional, so there's no real answer.

tl;dr I think B.
Consider a void in space, no gas, no gravity.
Place the cube with no velocity.
Create on stationary blue portal.
Create an Orange portal moving at, say, 10 m/s, constantly, with an intercept with the cube.
If there was nothing to stop the Or-portal after the cube has been transfered, the cube should have speed. Why? Becuase as the atoms of the cube began to arrive at the Blue portal, are they just going to pile-up and intersect? No. They will move "forward" and make room for the next plank of elements, at a speed of 10 m/s. Why would it stop after the cube is consumed? I don't see a reason.
And an appeal to Conservation of Energy: These are hypothetical portals, why do they need to conserve energy, hell, black holes may have been observed to NOT conserve mass...

Now, let's say the cube was "resting" on a plate (still no gravity)
The orange portal was mounted on a plate so that the portal would stop moving once the cube is "consumed"
After translation through the portal, the plate would not ground the cube, aka stop it. The cube should continue with it's 10 m/s

Conclusion: I think that, given this extremely hypothetical situation: B

P.S.: Remember in Portal 2; when you cut the neuro-toxin feed-pipes. What did you mount the portals on? Moving mother fucking platforms. Games like portal aren't good references when it comes to physics, I think.

>>4320868
Those platforms don't move perpindicular to the portals, but I agree with everything else you said.

>>4319956
>>4319956
>>4319956
>>4319956
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>>4319956
>>4319956
>>4319956
>>4319956
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>>4319956
THIS ENTIRE PROBLEM IS USELESS BECAUSE OF THIS

>>4320884
hypothetical. pretend she didn't tell us that. (besides, no such thing as absolute rest)

derive the impossibility of portal ends being in relative motion.

>>4320884
I get pure enjoyment out of the fact that I can sometimes legitimately call someone retarded. This is one of those moments.

You, good sir, are fucking retarded.

Hey, wouldn't the air that's going into the moving portal be coming out of static one? And it would have to displace the air that's on the other side, creating wind.

>>4320914

I am disappoint

>>4320868
There is theoretically only one portal.

cant someone just make a map to demonstrate this

>>4321115
No, because it's just as easy to draw stupid bullshit as it is to say stupid bullshit. One of them just takes longer, and people are just gonna argue over it anyway.

>>4321124
i feel like you're just using my post to make a point because it doesnt answer it in any meaningful way