They were already in EU due to trading but this climate makes it much more inviting for them to settle down. Fret not it’s just a bullet wound if you do get stung by it
Don’t even start with that “I read that as” “the hero we need” or any other reddit catchphrase bullshit. Go back to reddit if you are going to use those annoying af sayings. We don’t need it here.
Für meine deutschen Freunde : Die asiatischen Biester sind meldepflichtig. Falls ihr eine seht, Foto knipsen und dem Regierungspräsidium mitteilen. baden-wuerttemberg.nabu.de/…/17059.html
I have considered the repercussions of importing Japanese honeybees (which are able to defend themselves against Asian hornets), but I don’t know enough about bees to see if it would be a good idea.
Here’s how I always phase it. Imagine you have a shovel and you are using that shovel to flick some dog shit into your neighbours garden.
With no portal the shit hits the shovel and you flick it, transfering the speed of the shovel into the turds. You stop the shovel and the turds fly away.
Now imagine the shovel has a big rusty hole in it. So it’s like a n shape. No portal yet. You go to flick the dog dumps but you just pass straight over them with the hole and the dumps go nowhere. The dumps have gained no momentum because nothing touched them and transferred that to them.
Now put a portal on the end of the shovel. As you sweep it over the cack has anything touched them? Has any object transferred it’s momentum to the dog eggs? No, so the dumps just gently tumble out of the other side of the portal.
But even in the image example, how would that work? The people have no momentum, they wouldn’t flop out, just fall back through, and then stay half in half not. According to you, air resistance wouldn’t even push them out because as soon as it goes through the portal the air is not moving relative to the people. I think your blatant lack of respect for relativity is unnerving and gets super confusing very quickly.
Imagine there being 2 portals on the shovel one on the front and one on the back Whatever passes through remains in the same place. THIS is the actual analoge for the rusty hole. Entering the first portal the shit gains the speed of the shovel but since the exit portal is also traveling with the same speed but facing the opposite direction, it effectively cancels out the previous speed gain. Imagine it like the first portal adding one unit of speed to it and the exit one adding minus one unit of speed because of the opposite direction.
So now with one portal on the shovel and the other somewhere on a wall the shit gets accelerated and you will feel a force acting on the shovel that decelerates it’s swing.
Velocity is relative and this is why it works. If velocity wasn’t relative then Einstein would be wrong and many of the effects we see in the real world could never happen.
I didn’t have a proper argument to begin with dude. It’s a meme about video game concepts and I’m talking about flicking shite with a shovel. What made you think this was a serious debate?
I think that’s a very strong argument and a great metaphor, but you forget relativity.
All reference frames are valid - you could say the Earth and the people are moving and the train is stationary, you could say the train is moving and the earth and people are stationary, or you could say they each have a vector moving around the sun or anything else
But when you travel through a portal, the only valid reference frames are you and the entry portal. Your momentum relative to the Earth doesn’t matter - why would it? You can open a portal to the moon and jump through, and we see momentum is preserved. The Earth isn’t a special reference frame, it’s just the most noticeable one.
So let’s pick the reference frame of someone on the track. Let’s look through the portal and say there’s a sign on the other side - as it approaches, you’d see a sign approaching you through the portal. Relative to you, through the portal the sign is moving at 30mph. The portal passes over you - you haven’t moved, but you enter a new reference frame, a frame in which the Earth and everything on it is moving at 30mph
As the people on the track are moving at an accelerated speed of 0 m/s, normally a train would apply the full force of the train moving to the meat bags human ethic problems on the tracks.
As newton's first law states F = m*a, or Force = Mass * acceleration
F = x * 0 = 0 N of force
thus, they could just plop out as if falling after having a chair removed.
But how would the objects get on the other side then? The receiving side isn’t moving, so the objects essentially need to be pushed through the portal at the speed at which the train is moving, resulting in B. The only way A could work would be both portals moving at the same relative speed.
But with a hula hoop, both sides of the “portal” are moving at the same speed, so the momentum of the subject is unchanged. That’s not the case presented in this post
Except the momentum changes with portals most of the time anyway. Momentum is a vector, not just a scalar, meaning momentum has both a scalar and a direction component. And that direction component usually must be conserved as well. But portals change the direction of momentum all the time relative to the orientation of the entering and exiting portals. If the direction of the momentum of the object is relative to the orientation of the portal, then it makes as much sense that the scalar of the momentum would be relative to the velocity of the portal as well.
Energy is not conserved either, which is why the infinite falling box arrangement means the box keeps accelerating downwards gaining kinetic energy even though it started out with a much smaller, finite potential energy. Portals and conservation do not mix well.
There is one segment in Portal 2 where you need to cut some tubes that transport neurotoxin, and for that small segment only, the game allows moving portals. https://youtu.be/OrAHvenjZpA
A, since portals cannot transfer momentum from the tram to the victims.
To put it another way, if you were standing and the portal was pushed towards you by a tram, do you think you would be launched out of the other side at that rate?
There might be some increase in momentum as the part of you that went through the portal first gets pushed forward by the parts of you that get pushed forward after, but it's not going to be as dramatic as the momentum you would have received being hit by the tram.
Most likely you would stumble forward and fall down or have to catch yourself.
Portals maintain velocity. Velocity is relative. Therefore the velocity they maintain is the relative velocity of the portal and the subject. Any other way and there would be no consistent way to pass any moment when passing through a portal.
After thinking about it longer then i care to admit I think i finally agreed with you.
As you said it is all relative, from the prospective of the moving portal. You could say it isnt moving at all but the entire world around it is moving, thus when people enter the portal from the portal’s prospective they people are the ones moving and will continue moving when they exist.
Hmm tlnit that i typed this out I feel like i didn’t do a very good job. Owell the answer is B.
I think Portal solved this conundrum by saying portals can’t move.
Energy is relative when there is a frame of reference.
When the tram-portal is the frame of reference, the person has the energy. And speedy thing goes in, speedy thing comes out.
Using Portals canon, the person cannot be the frame of reference (ie 0 energy), because the portal has to move for that scenario - which is Portal-ly impossible. So the person has to come flying out.
If you break Portals canon and say that portals can move, then then the person would likely be super-compacted (matter transporting on top of existing matter) into a singularity or just destroyed.
They totally can move though. In one of the puzzles there’s a button that makes part of a wall angle itself so that you can propel yourself forward, and the portal on it will move.
May be remembering wrong but I thought any wall movements like that one had to be done before you shoot a portal onto it, because if you do beforehand it'll poof away when you move the wall.
I remember that.
It’s a timed puzzle.
The wall moves on a button push, and moves back after an amount of time.
The portal is destroyed when the panel moves.
I mean, portals are flawed.
Anything moving through a protal experiences acceleration, unless the exit-portal is at the instantaneously-exact position of the entrance portal.
There has to be rules and limits that are ignored if portals are to exist, which is what the hypothetical situation is presentin5
It’s canon that they portaled between earth and moon. For a portal to be stationary relative to both, it has to be moving relative to its opposite end.
Frames of reference matter. Whether the train or the people moving happened it doesnt matter to the portal. There is net movement and the momentum is the mass of the person moving x the speed of the train.
Imagine the train was moving the speed of light. If the person exiting the other end of the portal wasnt coming out at the speed of light their body would come out like a soup. All the atoms in their body compressing to escape at some randomly low speed… actually it might make a tiny black hole on the other end as the atoms compress infinitely.
A portal is as another commenter has framed it, essentially a hula hoop with a different space on the other side of it.
It doesn't matter how fast a hula hoop falls over your body. You are not going to be launched out of the other side of the hula hoop even if the hula hoop is moving at the speed of light.
If the hula hoop is moving at the speed of light you are more likely to be killed by the shockwave of all of the atoms in front of the hula hoop compressing to adapt to the sudden intrusion of a lightspeed object with Mass, in which case it is very likely that you would pop out of the other side as some sort of soup, but that would not be because of your interaction with the portal inside of the hula hoop, or the acceleration of the hula hoop itself but rather the acceleration of the things around the hula hoop as it moved through space.
When im talking about speed of light i am assuming it will be in a perfect vacuum. If this was in ambient under normal conditions, a train going the speed of light would ionize all the air around it causing insane levels of heat.
So with the thought of it moving in a vacuum, if you look at the portal on a frame by frame basis every nano second you would see either
1 nano second in his entire body is within some imaginary dimension between the 2 spaces
The body gets infinitely squeezed in 1 space turning them into a mini black hole
They leave the portal at the same rate they came in
These are my 3 options, i dont see how it can be any other way.
I think that the velocity of the tram has nothing to do with the velocity the people it is running over until it actually runs them over and transfers momentum to them.
The portal puts a gap in between the tram and the victims, so there is no physical contact to transfer momentum. Momentum is a physical property, it cannot be transmitted without contact.
Therefore, in a frictionless vacuum the people must keep their original velocity and momentum regardless of the speed of the portal or whatever is pushing it forward.
If it worked the other way, Chell could not have leapt off of a ceiling and been launched out of the other side in the game. If portals transmit momentum without touch, then Chell would have first impacted an unmoving object with the same force as hitting the floor.
You can't have it both left moving objects fly though unimpeded keeping their original momentum and also have unmoving objects suddenly gain momentum from a moving portal.
The portal does not affect momentum, it is a break in momentum. Momentum does not transfer across portals.
The momentum stays with the object that passes through the portal.
Quantum states can jump long distances without particle interaction, this includes energy transfer (you just need a measurable latent possibility for particle interaction!)
The scifi answer that makes sense is that the space curvature around portal and shifting the object between two frames of reference (perhaps through frame dragging effects / gravity-wave like space warping) imparts momentum and it is conveyed from the portal as it is the thing which has to put in energy to correctly warp space for the object transfer.
The reason this is so confusing with different answers is that the portals don’t really exist, so inherently whether you say a or b is gonna depend on assumptions. In game they aren’t allowed to move so we have nothing to base it on to match game physics.
Here’s my take, momentum is a product of velocity. Velocity needs a reference frame. Without it, there’s no real difference in saying the portal has a velocity of 0 and the people tied up have a the velocity and therefore momentum, or the other way around. If we assume velocity with respect to the portal is what matters and is the momentum carried forward, then it should be B. If it’s relative to the earth or tied up people, then A.
If portals did not apply a transient vector to your momentum then you could not pass through a portal.
Take for instance the many times Chell jumps through a portal. Her momentum is maintained as she passes through the portal, allowing her and her robot legs to do truly stupendous feats of gravity assisted acrobatics.
If Chell was stationary and the portal fell on her, she would not be launched out of the other side with the momentum of the portal, she would just find herself sticking out of the other side of the portal.
Similarly, if Chell were to ride a moving platform up into an overhead portal, we would expect the top half of Chell's body to pop out of the portal without being accelerated by anything other than the moving platform on the bottom of her feet.
Therefore, unless there is some strange unknowable physics that we will not be able to discover until we develop portals of our own, the most likely outcome is that the victims on the tram would not gain any momentum as the portal was pushed into them, and they would plop out safely on the other side.
You can say you can expect, but you really can’t, because if you’re talking about momentum you’re talking about velocity and you need a reference frame to define velocity and therefore momentum. Let’s pick the sun for instance with the assumptions of A. So if we just have one portal pointing one direction and one portal pointing up and chell walks in, you should blast out straight up at 66,000 mph plus the speed she was walking then. I think you could make the reference Frame to earth and try and get a, but that would create problems too.
I think B, velocity relative to the moving portal, would be the only way to maintain some kind of consistency in game if you were going to have moving portals. Your examples are most consistent with B. A portal falls on chell, how fast does she come out? The speed the portal fell on her of course. And then she stops going out once the portal stops moving because it hit the ground and has stopped moving and they no longer have any relative difference in velocity. You could also say in the platform example that the platform was sitting still and the portal was moving down, you would emerge out the portal at the speed the first portal was moving down. Both should be equally valid ways if you want to maintain some consistency. But all of this is probably why they don’t allow moving portals in the first place.
In the end though these are definitely strange unknowable physics, portals don’t exist, so really you could make the game however you please, either one is perfectly valid, you could just say any velocity on the other side is whatever it was in relationship to the earth before going through, but that’d be weird, because how fast do the people move out of A then? Do they fly out at the speed of the moving portal and then suddenly stop mid air and plop straight down? If you’re not moving faster than a moving portal does is become brick wall and smash you out of the way so you don’t gain any velocity in relation to earth so A can be maintained? There’s no way to test it in the current games. Hence the endless arguing. But I think B would be most consistent and allow for some really interesting puzzles though, especially if you had two moving portals! Or maybe 3d portals that can sit in the air and allow full movement through them in any direction to help make it possible. Portal 3? In VR with depth perception to accommodate?
The only speed that should be relevant is the object’s speed relative to the portal. Anything else is a distraction. The physics don’t care if you are hurtling at it or it is flying at you, both scenarios are equivalent. The only way to maintain conservation of momentum is to assume your exit speed relative to the exit portal equals your entrance speed relative to the entry portal.
If it did work the other way, well it wouldn’t assuming your exit speed is equal to your initial speed, relative to the exit. That means your speed is 0 as you “exit.” This leaves us with two possibilities. Either you are smashed into a 2d plane and physics gets very concerned, likely forming a teeeeeny tiny black hole. Or the incoming matter behind the first bits will push the first layers through, which, will just wind up back at the starting point, as they will cascade into each other at a speed defined by the speed of the blue portal, being indistinguishable from the projectile interpretation.
it’s relative to the earth or tied up people, then A.
If it is relative to the earth, they would be crushed at an atomic level.
Imagine the trolley-portal is passing around a tape measure at 10m/s. The tape measure is stationary on the earth. After 10 seconds, 100m of tape has entered the portal in a straight line. For me to have 100m of tape in a straight line at the exit, the end of the tape has to be moving away from the portal at 10m/s. Given that “crushed into a singularity” is not an option, we can assume the velocity cannot be relative to earth, and must be relative to the portal.
All motion is relative. To understand how the people will move, we need to look at them relative to the portal. If the trolly is moving at 5 m/s relative to the ground, then the people are moving at 1 m/s relative to it. So they enter the portal moving at 1 m/s and exit at the same speed.
If I stick my arm in a stationary (relative to earth surface) portal, I expect my arm to stick out of the exit portal. If the exit portal is moving at 10m/s over the earth, I expect my arm to also be moving 10m/s over the earth. My arm is stationary relative to the portal, but the portal is moving.
If that portal is moving toward a standing person and I make a fist, I expect my fist to hit that person at 10m/s. I am stationary relative to the earth; they are stationary relative to the earth, but my fist is moving at 10m/s relative to the earth. From their perspective, I punched them. From my perspective, they ran into my fist.
If I look through the portal, I will see them approaching me at 10m/s. They will see me inside the portal, approaching them at 10m/s. When the portal passes around them, they will not feel any change in their velocity, they will just collide with me immediately after the portal passes around them. To them, the earth will seem to suddenly be moving at 10m/s.
yeah, all movement is relative, if it was B then the relative movement between the people and the train would have changed, if it’s A then it’s conserved
A portal that faces downwards into another portal is effectively a perpetual motion machine. Drop a ferromagnetic object into the loop and wrap some wires around the loop, now you have an infinite electric generator.
I think B and maybe it’s easier to explain my reasoning with a more dramatic example. instead of people on a track, maybe the trolly is heading towards a 50 foot horizontal pole. when the trolly comes to the pole at 90mph, the pole is not moving. but after the trolley’s portal has “swallowed” 40 feet of the pole, all 40 feet of that pole are exiting the portal at 90mph, being pushed by the 10 feet of pole that the trolly is still “swallowing”, so the momentum of 40feet worth of pole would continue to launch the remaining mass of the pole out of the portal and it would be launched out instead of flopping to the ground.
if we go back to our people on a track example, I think this would also kill them as for people on either side of the portal, it would feel like they’re being ran into at 90mph by the people on the other side of the portal.
Yes, I also thought of the pole example. It would feel like a wave of gravity suddenly shifting around them. I do think it would be less dangerous than a direct collision at the same speed, but only by a little - the danger with sudden deceleration isn’t the fact that it’s sudden, but that it is almost always uneven, it rips things inside you apart or collapse them together. But the portal would be a very clean uniform wave of pressure moving over you, so it could still cause damage by compression over one dimension (in the direction of portal movement) but most other forms of impacts will be missing
I’ve seen this debate about the outcome of the moving portal. I’m pretty certain that because of inertia, and the people aren’t moving, they will just plop out the other side. Think of it like moving a hoola hoop through the people. That’s basically what the portal is.
The hoola hoop has inertia and is moving, but it doesn’t actually come in contact with the people, so it passes right around them. There’s no way for the people to have instant acceleration because the porta did, otherwise it’d be like them hitting a brick wall and they would probably explode
Fully disagree on concept. The thing with the portal is solid matter moves through at a constant rate.
If you have a portal moving towards you, at say 2 MPH and you are holding your arm out, From the other side of the portal, they would see your arm coming out at 2mph. Any other result would involve compressing or stretching your arm.
Lets say further here. a man dangling his legs off the back of a moving cart. Man is moving 20mph forward, portal trolley is chasing him at 22MPH. As his feet pass through the portal, they would start coming out the other end of the portal at 2mph.
As a result I concur that the only logical exiting of a portal. |travler velocity - Entry portal velocity| + exit portal velocity = objects exit velocity.
Now the real physics debate would be what happens if 2 portals were moving forward and someone was in the path of one. The only logical conclusion that fits my mind there, is instant compression
Yeah, the imparted momentum has to be something like the averaged vector between the two, which does cause compression if you enter a pair of portals both moving your direction.
Momentum is relative.
If you say the portal is stationary, and the person is moving then B makes sense. However, this is just changing the frame of reference from following the tram to following the person.
Changing the frame of reference (from tram to person, or from person to tram) doesn’t change the velocity/momentum/energy (it’s just the person is moving towards the tram or the tram is moving towards the person).
The acceleration the person would experience is likely similar to if the person just gets hit by the tram, however in Portals canon it is nonexistent.
Because, as you say, the person is accelerated. However, the acceleration when using the tram as the frame of reference is still 0 when you account for the rules of physics a portal would break. Even changing the direction of travel would be acceleration.
Like, if the in-portal and the out-portal were back-to-back where there was absolutely 0 distance between them, anything passing through the portal would experience 0 acceleration - no change in direction, it might as well be a standard hoola-hoop.
If the portals were side-by-side facing the same direction, anything passing through the portal would experience twice the acceleration of running into a wall - like bouncing a ball off a wall. Once going into the portal (forward motion) and once coming back (backwards motion), because the object has to completely reverse it’s velocity.
And considering that things going into portals do not get damaged (and chel doesn’t lose health) it’s fair to consider that objects observe 0 acceleration.
But portals moving is outside of the Portals canon because it highlights that an object experiences acceleration when passing through a portal. And the acceleration is (or is near) instantaneous. And the object does not suffer from this.
The problem with your hoola hoop example is that it keeps moving after you go through it so that you have the same relative velocity. However, in the portal example, the exit portal is stationary, so in order to stay the same relative velocity to it when you exit is to speed up yourself, as in B.
Lets say the train is moving with 10 meters per second. That means that the people will enter the portal with 10 meters per second. Therefore, they will leave the other portal with, you guessed it, 10 meters per second. Henceforth, they will be traveling with 10 meters per second after leaving the portal. 10 meters per second.
As the object enters the first portal then the inertia of the far end of the object that is forced to pass through will need to be accelerated in the space outside the second portal to pass through, acceleration which is induced by being pushed by the other end of the object still outside the first portal.
In other words, pushing a portal onto an object pushes that object with half the speed of the portal. This will likely require energy put into the portal itself to maintain it, which needs to come from the train.
The would be moving at 10 meters per second in regards to the train that didn't touch them, the same as the were before the train got close enough to touch them.
Think of it the other way. If the went into the stable portal and came out I'm from of a moving portal, what would happen?
The portal would move forward and swallow them up and spit them back out the way they came in.
They would not have accelerated in the process. They wouldn't fly out the portal they just walked in at the speed of the train. The train didn't touch them so it can't transmit any of its momentum to them.
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