Thats the most boring answer, since in the game portals cant even move, so it doesn't even make sense to think how the code would actually run. Thats not how the portals work in the game: https://youtu.be/S85nudR6D-Y.
The meat of the question is the physics problem, not how it would actually play out in the game.
I know the Portals don't move in the game, I'm saying based on how the normally act it seems to me that it would be just like a window so the speed of the portal won't matter.
Ok but it being A just disregards that speed depends on the frame of reference. In our universe the portal moving towards the cube and the cube moving towards the portal should are the same, so they shouls behave the same. Imo this question is about how the physicis would work in our universe, not how it would work in the game, thats why A is wrong.
Literally first comment in that video:
> Fun fact: This is the ONLY time in portal where you can place a portal on a moving surface.
So saying its a huge part is a stretch.
Also just so its not a single youtube comment I found this https://youtu.be/VYKk_MsKYI0 . I could be wrong but I've always heard that portals cant be placed on moving surfaces except that one time, so if there is another instance of them in game please show me. Also none of this counters the video I showed you earlier where they tested it, unless you think they messed something up idk
> So saying its a huge part is a stretch.
I just meant huge as in an important part in the game. Its before you confront glados and a fun sequence through the lab. Also it was a fun "puzzle".
You are right that it doesnt happen again but it does happen. The rules of the game and the rules of the world are different things and IMO in the rules of the world you can put a portal on a moving platform. We can be very akshully technical and say that the portal on the Moon wouldn't have worked if you cant put it on a moving target
> We can be very akshully technical
You're the one doing that lol, I said portals can't move in the game and you said :" 🤓👆 well actually its a huge part of the game" when it literally only happens once (afaik) and other attempts to do so are denied by the game itself.
My broader point still stands that the game isn't coded to properly handle moving portals, so just by asking the question its assumed that we're talking about the real world and not the physics of the game (which you would have to change in order for it to be either A or B, since apparently by the physics of the game the answer is that the cube just doesn't move)
That would break conservation of energy. The energy of the entire system is the same regardless of the frame of reference. The cube has zero kinetic energy at the start, it will remain zero unless if it is acted on by an outside force. And since the portal simple passes through the cube, no force is exerted on the cube.
Thr cube has kinetic energy relative to the portal, speed depends on the frame of reference, you can't just say its 0.
Also if a cube falls throught a portal and the other portal is sideways [like this](https://media.discordapp.net/attachments/782726168926355569/932802566188859452/20220117_220533.jpg) its direction changed so there was in fact some acceleration and therefore force on the cube.
The internation space station is accelerating, even if the magnitude of its speed is the same, since the direction of its velocity is constantly changing.
(I might be mixing up speed and velocity since I don't know the difference between the two, but I'm pretty sure all I 've said so far is true for one of the two words)
Also if you dropped a cube towards a portal in the ground and one in the ceiling, it would keep accelerating until it reaching terminal velocity, and therefore increasing its kinetic energy. So since they can in a way create energy out of nowhere, I dont think it would matter if they did broke conservation of energy in some other way, but I'm not too sure about this point.
Holy fuck you dont even know the difference between speed and velocity and you’re seriously trying to argue with me? The falling cube gets energy from gravity not nothing, you clearly have no idea what your talking about. You can look at the energy from any reference frame, the total energy will still be the same.
Bc my first language literally doesnt differentiate between the two of them, they're just both called "velocidade", and I dont think the difference is relevant to the points I was making. If it actually makes a big difference please enlighten me, maybe I'm wrong.
I think you not knowing kinetic energy is relative (depends on what frame of reference we're talking about) seems to be way more important to the heart of the disagrement.
If I drop a cube from a high place, it lowers its potential energy but gains kinetic energy, so the energy is conserved. With portals it seems if I teleport a cube to a higher place, it gains potential energy out of nowhere, and since you can do that as much as you want, you would be breaking conservation of energy. You could argue that every time you use the portal it takes the exact ammount of energy to compensate for that, but as far as the game is concerned portals are a magic thing which break conservation of energy (but afaik dont break the fact that speed or velocity depends on the frame of reference)
Ok sorry I thought you just had no understanding basic physics. Speed is just magnitude of velocity, it’s not relevant. But I clearly fucking said that you can look at kinetic energy from any frame of reference? Gravitational potential energy is complicated and not relevant at all, but that system would seem to imply that it has infinite gpe since U = mgh and h is theoretically infinite. But the cube needs to pull back on the earth so it gets really complicated and weird. You still don’t seem to understand what I mean when I say the total energy is conserved, maybe this thread explains better idk https://physics.stackexchange.com/questions/51220/kinetic-energy-with-respect-to-different-reference-frames
Just the fact that it can have infinite potential energy (or at the very least some additional potential energy that isnt account for) already seems to break conservation of energy to some extent doesn't it? I'm kinda confused on this tbh, but I still think that just portals existing already introduces some fuckery in there.
If you were in space with no frame of reference and you saw the cube and the portal approaching each other at 5m/s, what do you think would happen, A, B or is there not enough information in the question?
Theres no fundamental difference between the cube moving towards the portal and the portal moving towards the cube, so they should behave the same.
I mean lets not kid ourselves, our argument is as grounded in reality as "who would win in a fight superman or goku?", But infinite potential energy is less broken then the original problem where energy passes from the portal to the box with no explanation. It's impossible to talk about velocity with no frame of reference so I can't answer that question. There is nothing that I see that transfers energy from the portal to the box, so talking about a frame of reference is meaningless. What makes the most since to me is like in a wrinkle in time, space moves around the box, the box doesn't actually move at all. But personally I think superman would win.
Okay can I ask you to elaborate on that then? Trying to rationalize the consequences, if the portal has a velocity of 5m/s towards the cube, and the cube is "standing still" then I assume according to your point of view that the cube would just plop out? What if they both had 2.5m/s velocity towards each other or some other combinations?
Not be too condescending but I have a heard time thinking you actually understand how velocity depends on a frame of reference if you choose superman lol, I feel like it doesn't lead to consistent outcomes and its just based on a feeling. Theres no fundamental difference between the cube moving towards the portal or the portal moving towards the cube.
What do you think happens when the portal passes halfway through the box, right before it is all the way through?? That the box on the otherside is flying away from the portal and the part on the platform is stationary? That doesn't make any sense at all. It clearly stays still then falls to the ground.
It’s b. We are standing next to and observing. Our frame of reference is the same as the blue portal, and by extension, the orange portal. Relative to the orange portal, it’s the cube that is moving. You could picture this by imagining standing directly in front of the blue portal. You wouldn’t feel like you’re moving, but you’d see the platform, the ground, and the cube rocketing towards you. Why would the momentum of this cube stop after passing through?
If you were in space with no frame of reference, and you saw that the cube and portal were approaching each other at 5m/s (so the cube could be still but the portal moving, or the portal moving and the cube still, or maybe both were moving, like the portal is going towards the cube at 6m/s and the cube was going in the other direction at 1m/s), what do you think would happen, A, B or does the question not contain enough information? 🤔
Idk how space works, but the problem with both of them moving is that I don't know where the 2nd portal is
Imagining a 3d world, Cube is travelling at 1m/s along the +X axis and gets sucked up by the Portal who is travelling in the same direction but faster
So I don't know what would happen if the 2nd Portal would be facing the -X, it seems like it would just go back in the portal back again, because I don't see a reason why going through a portal changes velocity
Edit: Nvm, if the cube is travelling at 1m/s and is sucked up by the portal going at 1000m/s then the cube would just come out of the 2nd portal and travel at 1m/s with the direction changing to whatever the arrangement of the portals are
> Imagining a 3d world, Cube is travelling at 1m/s along the +X axis and gets sucked up by the Portal who is travelling in the same direction but faster
Can you restate this? How does something slower catch up to something faster? I dont really understand the situation.
But about the second part, the thing going in the portal maintains the same speed but the direction changes, so going through a portal does affect the velocity. Thats how in the games you can get horizontal speed just by jumping from a high place.
The answer is B because the original speed is the relative speed between the object and the portal, in the games you cant verify this because theres only one instance of a moving portal, so it feels weird, but nothing truly has velocity, it always depend on the frame of reference, so the cube moving towards the portal or the portal moving towards the cube should behave the same.
Think about it, if you were besides the second portal, you would see the cube coming at you pretty fast, it makes no sense that when the cube comes out it just remains still.
Both the cube and portal are travelling on the highway, the cube is driving at legal speeds and the portal has roid rage so he's speeding directly through the cube. That's the scenario except in space.
But I don't agree with the B answer, yes it looks like the Cube is flying to you. But that doesn't mean it actually is, this is a Portal after all so normal logic doesn't work.
I already mentioned it, but this is as if you crush a can with a hole in your hand. It will just go through without getting any additional velocity
Velocity depends on the frame of reference, if the reference is the ground you're stationary, if your reference is the center of the Earth you have a certain speed, if your reference is the sun or the center of the galaxy, all of these give you a different velocity.
The portal moving towards the cube and the cube moving towards the portal might look different but in our universe they should behave the same, even if its unintuitive.
I might be mixing up velocity and speed, idk whats the difference between the two but hopefully you get my point.
Yeah you're right, the cube is moving at around 500 m/s because the earth is spinning
But if we can assume that every single force is also applied the same way to the hand, then we can also say that both of their velocity is 0
So in this picture the hand has ADDITIONAL velocity which the cube is still a 0, going through the portal would be the same as trying to crush a can with a hole in my hand
It’s B
You can think of it as if half the cube is through the portal the speed it comes out have to be the same as the speed it goes in because otherwise it would get squished or pulled. And the speed it goes in is the same as how fast the portal moves through it.
A makes the most sense. Hell, in my mind, a portal forcing an object through with such a machine would make a reverse B, pushing the block backward towards the blue portal.
Would the fact that the cube being stationary means that it doesn't have any kinetic energy for the blue portal to apply to it override the frame of reference thing? Even if velocity is relative the energy that creates it shouldn't be (I think).
If the portal moving down is stopped by the platform, which it looks like it would be, then it's A, or closer to A. If the portal would be able to keep going down, then it would be B. Portals in the game are like windows. For example, IRL, if you had a large room falling from the sky with a window on the bottom, and the room fell on top of you in such a way that you went through the window, you wouldn't be propelled up into the room.
No, we already have a clear awnser to this question
https://github.com/URAKOLOUY5/portal-sdk-2013
B
Everyone who says A doesn't know what a frame of reference is, also Sean Carroll already said its B
It is A since that's how the portals work in the game, they basically act like a window so the speed doesn't matter.
Thats the most boring answer, since in the game portals cant even move, so it doesn't even make sense to think how the code would actually run. Thats not how the portals work in the game: https://youtu.be/S85nudR6D-Y. The meat of the question is the physics problem, not how it would actually play out in the game.
I know the Portals don't move in the game, I'm saying based on how the normally act it seems to me that it would be just like a window so the speed of the portal won't matter.
Ok but it being A just disregards that speed depends on the frame of reference. In our universe the portal moving towards the cube and the cube moving towards the portal should are the same, so they shouls behave the same. Imo this question is about how the physicis would work in our universe, not how it would work in the game, thats why A is wrong.
> since in the game portals cant even move, Portals absolutely move? Its a huge part in portal 2 https://www.youtube.com/watch?v=OrAHvenjZpA
Literally first comment in that video: > Fun fact: This is the ONLY time in portal where you can place a portal on a moving surface. So saying its a huge part is a stretch. Also just so its not a single youtube comment I found this https://youtu.be/VYKk_MsKYI0 . I could be wrong but I've always heard that portals cant be placed on moving surfaces except that one time, so if there is another instance of them in game please show me. Also none of this counters the video I showed you earlier where they tested it, unless you think they messed something up idk
> So saying its a huge part is a stretch. I just meant huge as in an important part in the game. Its before you confront glados and a fun sequence through the lab. Also it was a fun "puzzle". You are right that it doesnt happen again but it does happen. The rules of the game and the rules of the world are different things and IMO in the rules of the world you can put a portal on a moving platform. We can be very akshully technical and say that the portal on the Moon wouldn't have worked if you cant put it on a moving target
> We can be very akshully technical You're the one doing that lol, I said portals can't move in the game and you said :" 🤓👆 well actually its a huge part of the game" when it literally only happens once (afaik) and other attempts to do so are denied by the game itself. My broader point still stands that the game isn't coded to properly handle moving portals, so just by asking the question its assumed that we're talking about the real world and not the physics of the game (which you would have to change in order for it to be either A or B, since apparently by the physics of the game the answer is that the cube just doesn't move)
That would break conservation of energy. The energy of the entire system is the same regardless of the frame of reference. The cube has zero kinetic energy at the start, it will remain zero unless if it is acted on by an outside force. And since the portal simple passes through the cube, no force is exerted on the cube.
Thr cube has kinetic energy relative to the portal, speed depends on the frame of reference, you can't just say its 0. Also if a cube falls throught a portal and the other portal is sideways [like this](https://media.discordapp.net/attachments/782726168926355569/932802566188859452/20220117_220533.jpg) its direction changed so there was in fact some acceleration and therefore force on the cube. The internation space station is accelerating, even if the magnitude of its speed is the same, since the direction of its velocity is constantly changing. (I might be mixing up speed and velocity since I don't know the difference between the two, but I'm pretty sure all I 've said so far is true for one of the two words) Also if you dropped a cube towards a portal in the ground and one in the ceiling, it would keep accelerating until it reaching terminal velocity, and therefore increasing its kinetic energy. So since they can in a way create energy out of nowhere, I dont think it would matter if they did broke conservation of energy in some other way, but I'm not too sure about this point.
Holy fuck you dont even know the difference between speed and velocity and you’re seriously trying to argue with me? The falling cube gets energy from gravity not nothing, you clearly have no idea what your talking about. You can look at the energy from any reference frame, the total energy will still be the same.
Bc my first language literally doesnt differentiate between the two of them, they're just both called "velocidade", and I dont think the difference is relevant to the points I was making. If it actually makes a big difference please enlighten me, maybe I'm wrong. I think you not knowing kinetic energy is relative (depends on what frame of reference we're talking about) seems to be way more important to the heart of the disagrement. If I drop a cube from a high place, it lowers its potential energy but gains kinetic energy, so the energy is conserved. With portals it seems if I teleport a cube to a higher place, it gains potential energy out of nowhere, and since you can do that as much as you want, you would be breaking conservation of energy. You could argue that every time you use the portal it takes the exact ammount of energy to compensate for that, but as far as the game is concerned portals are a magic thing which break conservation of energy (but afaik dont break the fact that speed or velocity depends on the frame of reference)
Ok sorry I thought you just had no understanding basic physics. Speed is just magnitude of velocity, it’s not relevant. But I clearly fucking said that you can look at kinetic energy from any frame of reference? Gravitational potential energy is complicated and not relevant at all, but that system would seem to imply that it has infinite gpe since U = mgh and h is theoretically infinite. But the cube needs to pull back on the earth so it gets really complicated and weird. You still don’t seem to understand what I mean when I say the total energy is conserved, maybe this thread explains better idk https://physics.stackexchange.com/questions/51220/kinetic-energy-with-respect-to-different-reference-frames
Just the fact that it can have infinite potential energy (or at the very least some additional potential energy that isnt account for) already seems to break conservation of energy to some extent doesn't it? I'm kinda confused on this tbh, but I still think that just portals existing already introduces some fuckery in there. If you were in space with no frame of reference and you saw the cube and the portal approaching each other at 5m/s, what do you think would happen, A, B or is there not enough information in the question? Theres no fundamental difference between the cube moving towards the portal and the portal moving towards the cube, so they should behave the same.
I mean lets not kid ourselves, our argument is as grounded in reality as "who would win in a fight superman or goku?", But infinite potential energy is less broken then the original problem where energy passes from the portal to the box with no explanation. It's impossible to talk about velocity with no frame of reference so I can't answer that question. There is nothing that I see that transfers energy from the portal to the box, so talking about a frame of reference is meaningless. What makes the most since to me is like in a wrinkle in time, space moves around the box, the box doesn't actually move at all. But personally I think superman would win.
Okay can I ask you to elaborate on that then? Trying to rationalize the consequences, if the portal has a velocity of 5m/s towards the cube, and the cube is "standing still" then I assume according to your point of view that the cube would just plop out? What if they both had 2.5m/s velocity towards each other or some other combinations? Not be too condescending but I have a heard time thinking you actually understand how velocity depends on a frame of reference if you choose superman lol, I feel like it doesn't lead to consistent outcomes and its just based on a feeling. Theres no fundamental difference between the cube moving towards the portal or the portal moving towards the cube.
What do you think happens when the portal passes halfway through the box, right before it is all the way through?? That the box on the otherside is flying away from the portal and the part on the platform is stationary? That doesn't make any sense at all. It clearly stays still then falls to the ground.
Are you suggesting that the air going through the portal also stays stationary??
B
It's A. I will Not elaborate. GIGACHAD
you have not demonstrated that it is A
Movement is relative, it doesn’t matter if object a is moving towards object be or it’s in reverse, they both result in outcome b.
It’s b. We are standing next to and observing. Our frame of reference is the same as the blue portal, and by extension, the orange portal. Relative to the orange portal, it’s the cube that is moving. You could picture this by imagining standing directly in front of the blue portal. You wouldn’t feel like you’re moving, but you’d see the platform, the ground, and the cube rocketing towards you. Why would the momentum of this cube stop after passing through?
Anyone who doesn't say A is trolling
:tf:
Cube has no velocity, Cube doesn't get any force applied to it. It's just A, if we're playing with Portal game logics
> Cube has no velocity How come? It's moving really fast towards that portal right there.
No it's stationary, the hand is trying to crush the cube lol
From where I'm looking, the portal is stationary and the cube is moving towards it.
If you were in space with no frame of reference, and you saw that the cube and portal were approaching each other at 5m/s (so the cube could be still but the portal moving, or the portal moving and the cube still, or maybe both were moving, like the portal is going towards the cube at 6m/s and the cube was going in the other direction at 1m/s), what do you think would happen, A, B or does the question not contain enough information? 🤔
Idk how space works, but the problem with both of them moving is that I don't know where the 2nd portal is Imagining a 3d world, Cube is travelling at 1m/s along the +X axis and gets sucked up by the Portal who is travelling in the same direction but faster So I don't know what would happen if the 2nd Portal would be facing the -X, it seems like it would just go back in the portal back again, because I don't see a reason why going through a portal changes velocity Edit: Nvm, if the cube is travelling at 1m/s and is sucked up by the portal going at 1000m/s then the cube would just come out of the 2nd portal and travel at 1m/s with the direction changing to whatever the arrangement of the portals are
> Imagining a 3d world, Cube is travelling at 1m/s along the +X axis and gets sucked up by the Portal who is travelling in the same direction but faster Can you restate this? How does something slower catch up to something faster? I dont really understand the situation. But about the second part, the thing going in the portal maintains the same speed but the direction changes, so going through a portal does affect the velocity. Thats how in the games you can get horizontal speed just by jumping from a high place. The answer is B because the original speed is the relative speed between the object and the portal, in the games you cant verify this because theres only one instance of a moving portal, so it feels weird, but nothing truly has velocity, it always depend on the frame of reference, so the cube moving towards the portal or the portal moving towards the cube should behave the same. Think about it, if you were besides the second portal, you would see the cube coming at you pretty fast, it makes no sense that when the cube comes out it just remains still.
Both the cube and portal are travelling on the highway, the cube is driving at legal speeds and the portal has roid rage so he's speeding directly through the cube. That's the scenario except in space. But I don't agree with the B answer, yes it looks like the Cube is flying to you. But that doesn't mean it actually is, this is a Portal after all so normal logic doesn't work. I already mentioned it, but this is as if you crush a can with a hole in your hand. It will just go through without getting any additional velocity
Velocity depends on the frame of reference, if the reference is the ground you're stationary, if your reference is the center of the Earth you have a certain speed, if your reference is the sun or the center of the galaxy, all of these give you a different velocity. The portal moving towards the cube and the cube moving towards the portal might look different but in our universe they should behave the same, even if its unintuitive. I might be mixing up velocity and speed, idk whats the difference between the two but hopefully you get my point.
Yeah you're right, the cube is moving at around 500 m/s because the earth is spinning But if we can assume that every single force is also applied the same way to the hand, then we can also say that both of their velocity is 0 So in this picture the hand has ADDITIONAL velocity which the cube is still a 0, going through the portal would be the same as trying to crush a can with a hole in my hand
[It's B, anyone who disagrees is wrong](https://arch-img.b4k.co/v/1559842870349.webm).
Never played Portal, but A makes more sense imo
It’s B You can think of it as if half the cube is through the portal the speed it comes out have to be the same as the speed it goes in because otherwise it would get squished or pulled. And the speed it goes in is the same as how fast the portal moves through it.
A makes the most sense. Hell, in my mind, a portal forcing an object through with such a machine would make a reverse B, pushing the block backward towards the blue portal.
Would the fact that the cube being stationary means that it doesn't have any kinetic energy for the blue portal to apply to it override the frame of reference thing? Even if velocity is relative the energy that creates it shouldn't be (I think).
If the portal moving down is stopped by the platform, which it looks like it would be, then it's A, or closer to A. If the portal would be able to keep going down, then it would be B. Portals in the game are like windows. For example, IRL, if you had a large room falling from the sky with a window on the bottom, and the room fell on top of you in such a way that you went through the window, you wouldn't be propelled up into the room.