"The game won't let you put the portal on a moving surface" I believe the last object in the game that you put a portal through moves fast enough to go around the world in 25-30 days.
Two fun notes about the micro “theories” tackled in this video. 1. There actually IS a puzzle where you place a portal on a moving surface! There’s a scene in portal 2 where there’s a moving white panel near some cables or hoses, and you have to place a portal on it to sever the cables/hoses with a laser in another room. Funnily enough, that room is explicitly programmed to let you place portals on moving panels there, and I’ve seen a few Community Test Chambers that replicate that ability. 2. Something I’m curious to discover is how much atmospheric pressure did earth lose to the “moonshot portal”? Earth was literally venting atmosphere into the vacuum of space for that entire scene, which means that Earth’s air pressure wouldn’t be perfectly equal to 1 atmosphere any more. I realize that it’s pretty small scale by comparison, but I’m curious just how much atmosphere (or at least just how much air) was vented through the portal.
The pole would not snap in the line of the portal. It should stretch everywhere with the same force because it pulls on it self. Like when hidroforming, the force distributes equally. But in this case not on a plane but on the length of the pole so it could snap anywhere..
@@MyAramilprobably not the wield itself as that's the point of a wield, but near the wield in the area around that got heated and changed it's strength, so most of the time that area is less strong. Also I'm not sure exactly why tensile strength test pieces brake in the middle because it's not any weaker, it's maybe just that it's in the middle of the piece
Slight correction: it was actually Galileo who first proposed the theory of relativity, not Einstein. Einstein’s addition was introducing a finite maximum speed, which is known as the speed of light. Lorentz(who is famous for the Lorentz force law of electromagnetism) actually arrived at the mathematic used to describe this finite speed of light a few years before Einstein, by considering Maxwell’s equations, and how changing reference frame would affect Maxwell’s equations. Einstein did invent the theory of General Relativity, which introduces gravity as space time curvature.
its crazy how many things in physics are so closely related despite being 100s of year apart galelio was very close to being correct, but since the laws of em werent discovered yet he couldnt finalize it
i enjoyed this analysis, but it did bring up one more question about the moving portal and stationary object: lets say you have the box sitting on a table, and the portal is being lowered onto the table from above, but the other end of the portal is also on the roof, so he box will come out falling. at some point, there should hypothetically be more of the box on the other side of the portal, and therefore the gravity on the other side should suck the rest of the box through, even though it is stationary on the other side. but that also means that in theory, there should be an equilibrium point where you could remove the table, and the box would stay suspended in the portal being pulled both ways. i'm not sure if this understanding is correct however
What a fascinating concept! That seems accurate. The precision required to get it EXACTLY half and half would be worse than balancing a bowling ball on a tightrope, but it’s theoretically possible.
yep!@ it should be possible to float the box in this fashion. but in practice it would be infinitely difficult, like trying to levitate a nail between two magnets.
this could be used to justify the idea that the portals just don't need to be accelerating relative to each other. ....until one puts into account that putting a portal on *the moon* worked. so really i guess we should just assume we can't put portals on moving surfaces for gameplay reasons
My understanding of moving portals: They cannot exist because quantum tunneling requires an absurdly low temperature (4 Kelvin). Movement is directly tied to temperature; The hotter something is, faster it moves (on the atomic scale at least).
Low temperature does not prevent motion in any way. I can throw a hot or a cold ball at you and it’s not going to magically slow down or speed up. Temperature is related to the chaotic motion of particles around their equilibrium point inside the substance. It’s more analogous to a spring. If I stretch a spring in zero-gravity, it will contract and expand in place for a long time. Now, let’s say the spring has low energy, i.e. its parts do not move a lot. This does not prevent it from moving as a whole, since the stored energy is related to its displacement from equilibrium, and not from its starting position in space. Similarly, even if a portal requires low temperatures, it can still move as a single solid object with any speed it likes.
@@MozzarellaWizard @TheChiptide the quantum tunnelling theory is unconvincing to me unless particles are somehow entangled or something between both sides of the portals, but really all quantum tunnelling will do is allow an electron to phase through another particle. It just doesnt seem to map onto the characteristics of the portals in the game because it seems to work on a much larger scale than electrons and does more than just let you phase through walls. It doesn't satisfy my brain as being a possible theory. Also I recommend looking into internal energy again if its been a while since you've done physics, because you cant really compare movement on a macroscopic scale and subatomic scale. Thermal energy is the total energy of every particle in an object, but thats the random disordered motion of molecules. It doesn't typically interact or transfer in some way to become kinetic energy. Its quite hard to fully explain these differences without writing an essay, but the difference is essentially that this thermal energy is the *disordered* movement, whilst on a macro scale kinetic energy is the *ordered* movement of particles. It doesn't transfer back to kinetic energy (unless you count gases but they act differently to solids and liquids).
Accidently dropping the companion cube between portals as the infinitly sharp edge splits an atom apart causeing a hudge explosion as it rips proton from proton.
splitting atoms doesn't cause an explosion. nukes work on the basis of a chain reaction; the energy from splitting a single atom is enough to split multiple atoms. thus in a very short period all the uranium or whatever the fissile material is is then all split; all those like. >> 10^23 or so atoms splitting practically simultaneously releases extreme amounts of energy and causes the explosion
like the other response said, nukes work off of chain reactions, not splitting a single atom but also theres *so* much more space in an atom not being taken up by the nucleus than there is being taken up by the nucleus, that the event of this plane cutting through one of them is actually incredibly unlikely, as this plane would have to line up exactly with one of them
Easiest way to explain the portals is = a set of portals is like a open door and can be used as such; Just have one side of the door being in one spot and the other side is somewhere else and there you go, a portal.
Here's a paradox that I'm curious about. When you have two portals, one at a low altitude and one at a high one, and move an object from the lower one to the higher one, gravitational potential energy is gained. But no other forms of energy is lost- and energy is produced out of nothing. Inversely moving an object from a higher place to a lower place results in a loss of GPE. I know this can be shortcutted and have something to do with energy stored in the portal or portal gun itself, but is there a more satisfying answer?
If the portal doesn't need energy to maintain itself, then yes, it breaks the law of conservation of energy and can therefore be used to produce infinite amounts of it. Though what's more plausible is that the portal would require immense amounts of energy to maintain, enough to balance out the energy change of anything going through it, positive or negative. That would mean that if you could store the energy from a portal, you could do the opposite and shortcut a waterfall or something to produce high amounts of energy that way, not dissimilar to a water wheel
Here’s one idea. Gravitational potential energy isn’t magic. It’s calculated based on the, well… gravitational potential. For any given path the object takes, you can integrate the gravitational field to get the total energy it takes/produces. However, the portals simply connect distant points in space. So the gravity will “leak” through them, i.e. objects next to one portal will experience the gravitational field on the other side of the portal. This will result in a very unusual shape of the gravitational field. Now here comes the speculation part. It might be the case that the changes to the gravitational field will be such that integrating over any loop that goes via the portals will still result in a positive amount of energy required to complete that path. This requires some calculations to verify, and I’m too lazy for that😅
@@ehmareeeasiest solution I can figure is that portal energy consumption increases with the amount of energy required to move an object through it. So objects going through a pair of portals from low ground to high ground would result in higher energy consumption, from high ground to low ground would result in baseline energy consumption.
As someone with almost 1000 hours in portal, and well over 5,000 in portal 2, I 100% understand it being your favourite game, ever. It's nice to see a fellow enthusiast, everyone seems to not care nowadays. Here's a question I have: moving portals a re fun, but what about portals of different sizes? what if you had a blue portal the size of jupiter, and an orange portal the size of a door? as the atoms get bigger and smaller, I imagine a lot of very interesting nuclear physics would occur. But how? what are the ramifications? and which is less dangerous, making a small thing big, or making a big thing small? Now, what if you took the orange portal, put it in a box, and pushed the box THROUGH the blue portal, and then walked through a fizzler? where does the box go?
@@laierr but all joking aside lol, a lot of testing. there's always the community chambers, but there's also the main story, which not only is fun to run through, but also has fun puzzles, and interesting locations to explore. And you can always mix it up! Try to do chambers faster, try to do them with fewer portals, do them in VR, do them just because you can, etc. And there's hammer - make your own maps! It's tough to get right, but learning it is relatively easy, the tutorials are old though. but once you get the hang of it it's not so bad. Except for when it is. But I block those from my memory lol
I would like to see a part 2 on the portal 2 gels and how they would interact with various objects. Including OTHER liquids which portal 2 I dont think did much with.
Let's just assume that Portal has some weird crossover with FNAF Into the Pit and Oswald owns a Portalgun. What would happen if Oswald places a portal in the past and a portal in the present?
I think they’d theoretically work just fine, real wormholes work by folding space-time, meaning you could use them to travel through time just as easily as space!
well iirc the pit actually just transports you to a memory, so nothing done there actually influences the causality of the real world, only the psyche of the restless spirits inhabiting it, and idk if the other side even has "space" in the same way our world has.
6:45 small correction: the speed in is -10 out is 10, so you should add an absolute aka |Sin(c)-Sin(p)|=|Sout(c)-Sout(p)| 12:44 correct no2:well its fa×ma=fcut so its the classic question of 0×inf=? But if we said that you know cuz inf is not a number instead its a huge number(i guess undefined is also something cuz L/0=n/0) still no force is 0×n=0 so no you do still need force even if extremely low force needed
I was expecting to see a reference to the "crushed between two portals experiment" video in the pipe section of the video, but I can extrapolate from your explanation that anything put between two portals that are moving towards each other would be simply crushed by itself, pretty much like the pipe being tensioned by itself by two portals moving away from each other. Is that right?
I'm curious if the portal to the moon was left open would the earth's atmosphere all eventually equalise with the moons? does the moon have enough gravity to support that? How long do you think it would take to completely drain the earth's atmosphere?
The rod example is a weird one to think about, mainly cause we don't have true knowledge of how the portal acts. Would the act of pulling cause an energy strain on the portals due to the rod being a reference fixed reference point between them? Would the fixed portal size immediately collapse under this strain, or will the portal size shrink relative to how much force is applied to the portals until the portals collapse? Or will it happen as you described with the rod failing first?
personally i feel like the rod thing would happen; if i tried to pull the surface the portal is on with my bare hands, i think it would feel like i'm pulling a steel rod attached to a wall edit: and if the other portal is also on something loose and movable i think pulling one object the portal is on would just move the other object to keep the distance fixed
7:13 So if a portal is slamming down on you at like 10m/s would you get a concusion? or neck injury as your head is briefly moving at 10m/s relative to your body? Or does the portal catch up fast enough? what uf there were concrete blocks either side of you that suddenly stopped the portal at neck height?
4:25 I don't think you even need einstein to prove that the block will move cause when you think about it, for the block to come out of a stationary portal when it's going inot a moving one, it would need to "make space" for the rest of the cube. Because if it didn't move while coming out it would get smashed into superflat object as every thing is "placed" on top of each other
Every time I take notice of your subscriber count, I always feel like you should have more, you definitely make higher quality videos than other channels with so many more subscribers
About the first question, i always answered it without thinking with the same reasoning as in this video, BUT now that i actually think about it wouldn't it break the сonservation of energy? The box didnt have any mechanical energy to start with and than he gain same amount of it from thin air.
@A9to I think the big issue I have is that the portals are just acting as a hole in reality to bridge 2 points, so how is the portal moving even supposed to impart the energy to the cube?
And what if you put a portal exactly were another one is ? - Parallel : It would be as if there was no portal, an object would pass through the first and the second portal without diverging (maybe we live in a universe with infinite portals stacked in this way everywhere, we'll never know) - Parallel but mirrored : Then nothing could pass through it, as any particles would be pushed away by themselves (this would be the strongest barrier of all times)
I honestly always assumed and thought the moon thing had something to do with the pressure difference/the vacuum of space - Also, is it just me or can you actually see something visualizing seemingly air currents in the ending cut scene?!
When you said the portal would cut your hand off that would only be true if the portal is also very very durable because if you have something as thin as an atom in real life, you would just break it by applying any pressure
Just like the world's sharpest blade (only an atom wide) can't cut anything, the 2D edge of portal couldn't either. Just like you see standing in between portals, you'll just hit the walls of objects you connect.
8:28 With the 1-Meter Pole thought experiment, you're omitting the fact the portal you pull away from the other would have to pass THROUGH the BACK of the other portal in order to move further than 1 meter away from the FRONT of the other portal. So the REAL question here should be: What would happen if you moved the orange portal THROUGH the blue portal? Instant implosion of all of reality, perhaps? That's what is theorized in my science-fiction novel, anyhow. What does @TheChiptide think about this?
@@Dario-uj6qo No. If the 1-meter pole is going through both portals, you can only move the orange one 1 meter away from the blue portal before the orange portal would have to exit the blue portal. Presumably, the pole would stay intact and simply fall down in front of the blue portal, but that's ignoring whatever would happen if the orange portal were to exit the blue portal. Since they're both opposite ends of the same "wormhole", what would happen if one end came OUT of the other or went INTO the other, is what I was proposing.
The easiest way to explain the moving portal paradox is that if the speed were to stay zero then the moment it passed through the portal the cube would become stuck since, in order for the rest of the cube to pass through, the initial part of the cube needs to move out of the way.
The amount of possibilities portals have simply in the scenario of one in each side of a person is insane, what if i reach into the portal and pull my self up from my ankles? What if I tie a rope with itself through the portal?
The "moving portal paradox" is easily resolved if we interpret the rule "you can't place a portal on a moving surface" as "portals can't move relative to each other," ensuring momentum is always conserved. While the in-game scene where a portal cuts neurotoxin pipes breaks this rule, we can give Valve a pass for that one.
I'd love for you to extend on that whole gravity thing tho! Cause, like, if there is a portal on Luna and one on Earth, both on the floor of their respective celestial bodies, how WOULD gravity act tho? Would there be a semi sphere of approximately 1g around the portal on Luna and a semi sphere of less than 1g around the portal on Earth?
From what we see of portals, the implication is that gravity doesn't "go through" portals at all. Objects seem to be affected by gravity separately on each side of the portal. So if something was placed halfway through the Moon-Earth portal, one half of it would be experiencing Moon gravity pulling it down into the portal, and the other half would be experiencing Earth gravity pulling it down into the portal. The result would be the object being pushed through to the Moon side. But if the object were entirely on one side or the other, it would only experience the gravity from that side of the portal. For instance, an object that was placed right next to the portal, but not entering it, on the Earth side of the portal, would only be experiencing Earth's gravity.
I loved this video! I'm so glad I subbed to your channel, because every video of yours that I've watched so far has been amazing. Also, I always thought that the atmospheric pressure vacuum thingy for the moon shot was obvious, but I guess I just have to remember that not everyone has the same knowledge base (I was obsessed with space as a kid). Thank you for explaining these concepts in a way that is both understandable to newbies and not patronizing to experts. :D
Paradox 2: you can't guarantee the bar will break at the portal, all those forces add tension to the whole bar. The weakest point of the bar will most likely break first and that is probably the weld. Paradox 3: in the game you can stand on the bottom of two portals in walls. Therefore we must conclude the glowing aura exerts a force away from the infinitely thin edge strong enough to support your weight. So you would need more then 0 force to cut yourself.
Paradox 2 is solved right the thing is that we specifically trying to break the point touching the portal. We apply force to the same point, cause it is just in the portal therefor the mechanical tension is not experienced by the rest of the rod.
@@СачкоАртемОлегович You are not understanding how tension works, he points out how the red segment is being pulled in both directions but the thing is every segment is being pulled in two directions. In the tensile strength test that is called out as being an "identical setup" the portal is the two ends of the test rig so the red segment is the ends of the sample, note in the tensile strength test video the bar did not snap at the ends where the force is applied but ~60% of the way up. There is a difference in the test shown, the sample flairs out at the ends making those the thickest part and not the point of failure. If you ignore the weld and say you forge the bar into one piece then the braking point is determined by the grain of the metal, that is the molecular arrangement of the atoms! There will be slight variance of strength throughout the bar and the weakest point will fail under tension first. Grain is the areas where the metal is in the same crystal formation & orientation, larger grains can slip past each other easier then small ones so a region of the bar with larger then average grain size is where the bar will fail.
1. No real argument. 2. Now, the real question would be if any force would get applied to the portal or its surface itself. 3. Wait, even if it has infinitely small thickness, why would it have any length at all either? What material is providing the length in this case? 4. Wait, that’s obvious. Who thought it was gravity?
To my understanding the edge isn't infinitely small, but in fact 0, so it's an undefined property. Like they mentioned in the video, a proper portal would be a sphere. So at this point you try to have a 2 Dimensional object in a 3 Dimensional space, wich just doesn't work out.
Gravity and portals are actually a really interesting concept. For the sake of gameplay you're only affected when you pass through the portal even though it seems like there'd be a whole extra earth's worth of gravitational pull.
The thing about opening a hole from the atmosphere into vacuum is, nobody ever gets its right, to how fast the air moves and the force of the now lower pressure air close to the hole. This is to an extend some people think we would get sucked through a small hole instead of recognizing we could plug it with a single finger or the palm of your hand.
The idea that all motion is relative dates back to Galileo, and is called Galilean Invariance. Newtonian physics agrees with that. The problem is Maxwell's laws do not, and show that electromagnetic waves travel at a constant speed. Einstein figured out that that can be relative too, and if moving changes not only your idea of where something is, but when something is, it can cancel out, and you'll disagree on how far a photon travelled, how long it took, and even whether or not the clocks at the start and end were synchronized, but you'll still end up agreeing on how fast it's going. The rod wouldn't necessarily break at the plane of the portal. That's no different from any other plane. It could just as easily break at any point. The portal wouldn't be a perfect edge that can cut anything. It would certainly seem like it from our perspective, but if you have molecules or atoms hitting it, they wouldn't necessarily cut. After all, separating them means adding potential energy, and if there's not enough kinetic energy to do that, it won't work. Whatever electric fields they have extend out into 3d space, and can wrap around the portal's edge. I agree with the portal to the moon, part, but I think it's worth noting that you don't have to make a portal all the way to the moon to get a difference in pressure. Just opening one portal above another would do it. Not enough to pull you in, but I think it would still be a pretty noticeable wind. Another fun one is when you realize that time will at different rates for a portal on Earth vs one on the moon. The plane of the portal isn't fundamentally different from other spacetime. If you have a clock on each side of it, they'll show time passing at the same speed through the portal. Which means that if you wait long enough, the portals have to be sort of out of sync with time. Eventually, you'll have a portal to the past. And if you bring it back, you'll have a time machine. Incidentally, this means if the portal was shot at the speed of light to the moon, there would be no delay for it to open. Sure it takes a few seconds for the portal to get there, but from the portal's point of view, it's instant. But that doesn't mean the game was wrong. Just that the portal wasn't traveling quite that fast.
Combining the ideas of how cubes behave moving through portals and how the pole behaves when held in tension between portals, I'm curious how much a malleable object can be distorted by a moving portal or how much spin would be imparted on a non-malleable portal through moving portals.
Just want to say that since I followed your channel I've found a few other channels that try to explain silly video game logic with science, and while I didn't think any of them were bad, your videos are by far the ones that make all the math understandable the most, while also having a really great sense of humor. Hope you get to keep doing this channel for a good while!
The first case can be easily explained: if we consider "speed" as the time it takes the block and the portal to connect with each other, it doesn't really matter if it's the block or the portal that is moving.
I just have to say this is very high production value for a smaller(not small 27k is still a lot) creator. some bigger creators should take an example on this damn so good.
I had a moment during this when you explained how a portal would have to be spherical. The reason it clicked in my head was because you said the space between portals would have to be infinitely thin, which just doesn't compute. Then I began thinking about what a spherical portal would look like and how we would even interface with it? So me being me I just dropped the amount of dimensions to think about it in because obviously 2D portals are my specialty lol. when doing that I realized there could be a chance that 2 dimensional beings would have a similar question to the one I've posed above, leading me to believe that only 4 dimensional beings could imagine a way for us 3 dimensional being to interact with a 3 dimensional portal. Fun video!
I'm surprised this needed to be a video. That said, put a beam of light between two portals and see if you can break light or move so fast that light becomes a solid
I love this channel because I almost flunked high school physics and barely understand half of whats being said but then it's put in the context of a video game and suddenly I can almost comprehend it lol Also how can a meme be truly "dead" if it is being used and enjoyed? 🧐 A meme can only die if it is forgitten. As long as we use them, they are immortal 😌
Regarding the first one, an easier way to think about it is this: Any object that travels into one portal regardless of whether the object is moving or the portal is moving isn't going to exit out of the other portal all at once. The part of the object to touch the portal first is going to exit the other portal first. So if you have an object sitting motionless and a portal rushes towards it, the object is going to gradually exit the other portal at the same speed the moving portal is moving. Another way of thinking about it is that movement in general is preserved by portals. If the exit portal isn't moving and the object isn't moving but the entry portal is moving, that motion needs to be preserved somehow, so it is transferred from the entry portal to the object as it exits the exit portal, giving it motion. The implications of this are pretty scary though. The more dense and massive something is, the more difficult it is to bring it from rest into motion, let alone reach high velocity. It would seem however that this is done quite easily by simply accelerating an entry portal towards such an object. Regardless of the dense and mass, it should always eject out of the exit portal at the same speed as the entry portal's motion as it passes through it. The only solution to this I can think of is that the entry portal should actually lose speed proportional to the mass and density of the object passing through it to properly convert stationary energy into kinetic energy. As such, if the entry portal doesn't have enough energy to transfer into the object it should actually stop partway through the process of passing the object through it. Likewise, objects wouldn't eject out of the exit portal at the initial speed of the entry portal. The portal would slow down depending on the mass and density of the object the moment the object started to pass through, which would result in the object's ejection speed being proportional to the now slowed down speed of the entry portal.
Like the video only one thing I don’t agree with. Regarding the portal’s edge, there should not be an edge in the first place. A portal isn’t infinitely thin because there is no actual mass to the portal (best way to explain it) or there is no inside to it. If the portal has no space inside of it, which it shouldn’t have, then the portal would not slice your hand. Instead, I’d assume it’d be impossible to push passed it, thus, meaning it could not cut anything. Sorry if that explanation was hard to understand. Definitely not saying your idea is stupid since it seemed like a logically conclusion. I just had a little bit of a different idea and I might actually be wrong A question I’d like to hear answered is what would happen if you put a portal into another portal or what would happen if you split the surface the portal is on
The two portals with a beam welded to itself becoming a tensile strength testing machine raises a lot of interesting questions, though. It implies that a force can be exerted on a portal (or, alternatively, on the surface it's placed on) by an object going through it. But momentum is conserved between portals, and therefore so is energy, so where does the force come from?
Your evaluation of the first paradox does not appear to be correct. Relativity actually supports that the cube would not exit the second portal with any velocity. You must think of both portals as not two different portals, but two sides of the same portal. On one side you have environment A, on the other side you have environment B. The cube is only moving at a certain speed relative to one side of the portal, (moving relative to environment A.) The moment it passes through, if you were standing at the exit (environment B) looking back into the portal, you would still see environment A getting further away, because the other side of the portal is moving. in other words, the cube is still moving relative to environment A because the portal itself is moving. however, once it passes through to environment B, it will not have any velocity itself. (yes it is possible to not have any velocity but be moving relative to something else, in this case relative to environment A.) once this happens it will be subject to local gravity of environment B and be pulled downward, but not have any forward momentum. logically this has to be the case. if the cube exits the portal with the same velocity of the moving portal, then it's relative velocity to the previous reference frame would be double what it should be, since now both it is moving away from the portal, and the other side of the portal is moving away from it at the same speed. THAT SAID, because portals break the laws of physics, they also can break the equations we typically use for relative velocity and such because it creates new edge cases that don't exist in our physical universe. Therefore, it is possible that if the programmers of portal did not account for this, then you may experience different results in game than would would actually be expected to occur. for example, they may have hard coded that object exit with the velocity they enter the portal with no matter what, without accounting for the possibility of a moving portal. In this case, then results may vary. I am merely explaining what should actually happen if it were programmed correctly.
This logic doesn't seem sound - you say that environment A would look like it is moving away, but it would actually look like it was moving *towards* you, since the portal is moving forward. If the cube were to stop, it would look like it suddenly went from moving towards you to sitting perfectly still, which wouldn't make any sense. Thus the cube *must* come out the other side moving.
Regarding that last point, what I'm curious about is if the pressure difference between Earth and the Moon would actually create a strong enough aircurrent to actually escape the Moons gravity. The things being sucked through the portal would have to move at over 2 Kilometers per hour, otherwise they would just land on the moon somewhere
Cool thing about the ending of portal 2 with Wheatley in space floating. The speed of things sucked through the portal (pressurized to non pressurized) can reach speeds of 186000 mph and the moons escape velocity is o lot 18000 so it’s scientifically accurate he flew off instead of staying on the moon
16:04 little correction: the air isn't sucked into space, it's pushed. same thing with a hole in like the space station. the air is getting pushed out from the inside, not sucked out from the outside, as you showed with the ballon. but great video anyway!
You can not use mechanical advantage outside the classic physics and apply it to fields. When we are talking about really thin or infinitely thin edge. The length of the edge is also 0 in this case, which brings the contradiction. If we were to talk, about what would actually happen we must take into account general relativity and consider, what exactly will form on the edge of the portal.
3rd paradox: infinitely sharp edge if you think about it in a micro scale, the shortest distance between two atoms that are being severed is increasing since the space is discontinuous around the portal edges. That should still require some force to do if only to satisfy the energy requirements 2nd paradox: infinite rod this means that the portal experiences a force from the object as it resists being broken, which is interesting to me because the idea that a portal being influenced by the things that are passing through it isn't really present in any of the media I have seen. also, all the fields including gravity get messed up with portals lol. though i guess that might be partly due to us looking at 2d portals in 3d space
In Portal 1 you flat-out can stand in a portal with no other ground (both ends of a portal on a wall well above a floor), and Portal 2 it tries to shunt you to a side if you try standing that way. Question 3 is thus answered in-game, but you *are* arguing about hypothetical portals so that's still a valid chunk of video. I think the wormhole does have a miniscule thickness, though, but I don't have a source for that.
A portal that's 8ft by 4ft would have a surface "area" of about 100.53 square ft, with 14.7 psi * 100.53 si, that's about 1477.8 pounds of air blasting Chell into oblivion in the moon scene
Bonus question: What about gravitational influence? If you place two portals on ceiling and stand below one - youll have a window to an entire earth above your head. What will happen with gravitational pull if you have earth below you and portal-window to the same earth above you? Would you experience zero gravity (equi pull up and down) while standing below\\close to those ceiling portals? Bonus question 2: Place two portals facing one other. Stand between two portals and hold your right hand with your left hand thru the portal. Now pull left hand. Now start using legs to leverage against floor. You have force exerted by legs pushing you behind, force exerted (by your left hand in portal behind) on your right hand pulling you behind and you have force exerted on your left hand (by your right hand from portal in front fighting pull) pulling you forward. Will pulling forces be equivalent and you just push yourself by legs behind, or there will be some unexpected interraction?
For the first question: Gravity doesn't seem to travel through portals at all, so until you actually started to move between the portals, you wouldn't feel anything. The force in each direction would change depending on how much of you was on either side of the portals. If you put your hand through one of the portals, *only* your hand would be experiencing the gravity pulling it down. Because of this, while you could experience zero gravity if you were placed *perfectly*, the more likely outcome is that you would be pulled more from one side than the other, which would pull you more in that direction continuously until you popped out that side of the portal. For the second question: Pulling your left hand with your right hand through a portal would feel exactly the same as pulling your left hand with your right hand *without* a portal (you can try it out right now). There wouldn't be any new interactions here.
i would posture a different hypothesis with the pole between two portals. you see as you move the portals apart, it's not just the pole that gets stretched, it's the space between the two portals getting stretched, stretching and warping space like that would be impossible for any possible machine to accomplish, either the mechanism can't generate the force necessary to move the portals by a significant amount or the force required would just destroy the mechanism entirely in a way to how you can't swing an infinitely long pole to make the tip move faster than light, the amount of energy needed to move the pole at all would not be possible to achieve and if it were possible to provide that much energy, the pole would just snap. also interesting fact: while there are moving portals in portal 2, the motion is always perpendicular to the direction the portal is facing (left, right, up, or down).
@@xaigamer3129 it is the bouncy stuff don't know what you mean by purple tho, I remember only: blue (jump), orange(speed) and white (ground moon dust for portal placement)
Another question about gravity, shouldn’t infinite falling be impossible? You need 2 portals facing each other perpendicular to the ground. The object being dropped is getting pulled by the earth so it falls down and passes through the portal. Now the earth is pulling it from below and above through the portal. The bottom portal is slightly closer to earth meaning the gravitational pull out of the top portal is slightly stronger than the earth is pulling the object as it exists the top portal. Maybe didn’t explain this well but the end result is the object floating slightly passing through the portals.
What I don't like about the first scenario is the fact that the box has to have an infinitly high acceleration the moment the moving portal "touches" the box. Besides that: if the box shoots out of the other portal, the relative speeds change when crossing the portal. You got a moving portal, a still portal and a still box. Let's say the relative speed between the moving portal and the box is 10m/s. The relative speed betwenn the other portal and the box is obviously 0 m/s. When the moving portal approaches the box, the relative speed between the box and the portals change immediately. As the box shoots out of the still portal, the relative speed between the still portal and the box is 10 m/s.
I was wondering if you were going to get the air pressure vs gravity at the end. Never thought about it but now you mention it no one wants to trip goingthru the portal. I just want a portal gun for intereting things like moving the people blocking the aisle into the parking lot or something.
Thank you [UA-camr name here] for such such an amazing video! As an aperture representative i should say that it helped developing aperture science handheld portal device safety protocols You must be the pride of [UA-camr hometown here]! Thats truly unbelievable!
The first problem has a much more intuitive solution. If portal "consumes" an object with a certain length at a time, the object should appear from the other portal with the same length at a time. And (Length) * (Time) is a definition of speed. If it has speed of 0 relative to exit, it cannot exit. Therefore it cannot enter. Because you obviously should have the velocity to exit the portal. V(in) should be equal to V(out). If we have a meter-long rod and portal moving towards it at 10cm/s, it should disappear in the portal within 10 seconds. And it has 10 seconds to appear on the other side. So it should appear with a speed of 10cm/s relative to the stationary portal.
i'd argue that the edge of the portal needs a nonzero force to cut. when the edge of a blade is thinner than the gap between molecules, it doesn't matter if it gets thinner than that. it has reached the minimum number of intermolecular bonds it has to break. and that number isn't zero. you have to input energy to break those bonds by applying force. if it was an actual zero width blade, btw, i don't think it would cut at all. molecules either side of the blade would remain close enough to still have their interaction.
Two portals, facing each other, in a vacuum. A box in between them. Move the blue portal through the box, so it shoots out the orange portal (now moving toward the blue one). Before the box reaches the blue portal, move the blue portal back to its starting point, and then again toward the box. The box now has twice as much speed. Repeat this process. Can you accelerate the box to the speed of light in this way? This can be made even more complicated when we consider the speed of photons passing through the portals. In which, moving a portal should be breaking physics, yeah? Maybe moving one should actually move both of them?
To simplify the last problem basically chell basically turned the moon into a earth powered air rocket. Honestly considering what I've heard going on in deep ocean oil rigs I'm surprised chells arm isn't ripped off I'm kinda curious how much thrust that portal is shooting at chell and Wheatley.
If you haven't already would love a video about time dilation and how it doesn't exist. Example the light in an atomic clock moves a greater distance the faster the satellite goes that makes the clock tick slower because it takes longer for the light to catch up to the satellite. Not time dilation.
The 1 metre pole between portals, if you try to pull the portals apart, how are they physically interacting with the pole to try to stretch it? Assuming the pole is kept suspended in the middle of the portal (let's say with magnets for arguments sake), how is the force applied to moving the portal transferred to the pole?
for the third question if it was infinitely thin it would mean L/0 which is undefined so unless we define it as infinity a 2d portal would be impossible and we cant just define x/0 as infinity because it would also be infinity in the negative direction
the moon one is super simple, you went it with x velocity, and then popped out on the moon still with that velocity, with very little gravity to pole back, and hardly any atmosphere to bounce off of, so yeah you're gonna keep going shooting out into the void of space, the moon will pull you back down eventually (assuming you didn't enter with escape velocity) but it will be a bit, like shooting a rocket into the sky and waiting for it to fall back down, but now with the moons low gravity
You make two portals on the floor, you go in with 0 horizontal momentum. I think you keep moving up and down till the pressure on your body on both portals are equal
4:21 Albert Einstein isn't suggesting that, Descartes is suggesting that. Special relativity explicitly has to do with speeds relative to the constant speed of light in all reference frames. But the Cartesian frame of reference was popularized by Descartes.
For the first one, I’ve always imagined it as literally just a moving door. Yeah, there’s a chance the gravity can be different on the other side, but if you just had a moving wall (assuming it’s not a portal) fly around a cube and nothing happens, why should anything happen with portals? They are intended to be quite literally just doors Basically, the room is moving around the cube, wether it’s a weird worm hole or not
16:05 is not gravity, but it is pressure, so it is gravity. Making the surrounding air push you through the portal. In fact vaccum don't suck, heavy air push.
The only one I disagree with is the 3rd one. Yes an infinitely thin edge would slice, if it was actually an edge. But it's infinitely thing in both directions, the length in the equation is also practically zero and seeing as 0/0 is completely undefined I think it's just up to everyones own head canon, mine being that it would take on the properties of whatever the portal is on, usually a solid surface that you wouldn't be able to cut anything with
Personally, I didn't need this formula to answer this question. In fact, I think that formula isn't applicable to this situation at all. A plane that has no charge and is thin enough to pass in-between the atoms of your body would do just that. That's what neutrino do all the time (except, they are like points, not planes). The problem with the plane of the portal passing in-between your atoms is that now one of those atoms is here, and its neighbor is over there on the other side of the room. It wasn't a problem when a portal allowed for passage of matter and force interaction, but now there's no portal connecting the base of your arm and its end.
@@ghurcbghurcb I mostly agree, I was just showing that even if you tried to use the formula it wouldn't be applicable. The only way our ideas differ is that you head canon that it would have a similar effect to slicing, but not technically slicing anything, while I'd rather go with what the game seems to show, that being that you can't move through the side of the portal and it just seems to act like the wall that it's on
"The game won't let you put the portal on a moving surface"
I believe the last object in the game that you put a portal through moves fast enough to go around the world in 25-30 days.
By that logic every surface you put a portal on is moving because it’s on the earth which is moving.
And the first object you put a portal through moves fast enough to go around the world in one day.
@@DanielLCarrierwhat is it? I only play portal 2
@@CornbreadFish A wall. My point is that the planet is spinning around once per day, so a portal anywhere on the surface circles the planet in a day.
@@DanielLCarrier oh. Valid.
Old memes my beloved. Aged like fine wine they did
Agree
I miss when memes used to last, nowadays they only have a lifespan of a week with only very few exceptions
Hamburger 🍔
Thanks Yoda
bad Pineapple is
This really feels like old style game theory. The science, the intro, the old memes, it’s just perfect.
Those were my favorite vids! I still remenber the link hookshot video perfectly.
Two fun notes about the micro “theories” tackled in this video.
1. There actually IS a puzzle where you place a portal on a moving surface! There’s a scene in portal 2 where there’s a moving white panel near some cables or hoses, and you have to place a portal on it to sever the cables/hoses with a laser in another room. Funnily enough, that room is explicitly programmed to let you place portals on moving panels there, and I’ve seen a few Community Test Chambers that replicate that ability.
2. Something I’m curious to discover is how much atmospheric pressure did earth lose to the “moonshot portal”? Earth was literally venting atmosphere into the vacuum of space for that entire scene, which means that Earth’s air pressure wouldn’t be perfectly equal to 1 atmosphere any more. I realize that it’s pretty small scale by comparison, but I’m curious just how much atmosphere (or at least just how much air) was vented through the portal.
I think XKCD did the last question
There's an episode called "Can a portal destroy all life on earth" or something by Nerdist that answers the latter question
the air would only move at sound speed soo... not much i belive.
Fr, chell should have been launched to mars 😂
Aperture is a subterran laboratory so I dont think it was too much
The pole would not snap in the line of the portal. It should stretch everywhere with the same force because it pulls on it self. Like when hidroforming, the force distributes equally. But in this case not on a plane but on the length of the pole so it could snap anywhere..
It would snap at the weakest point. Which depending upon the weld strength maybe it, or other weak spots.
@@MyAramilprobably not the wield itself as that's the point of a wield, but near the wield in the area around that got heated and changed it's strength, so most of the time that area is less strong.
Also I'm not sure exactly why tensile strength test pieces brake in the middle because it's not any weaker, it's maybe just that it's in the middle of the piece
@@bablela26probably because that point recieves the pulling force from both sides equally, making that section easier to separate
@@vik.o1598hmm
@@MyAramilmay be*
Slight correction: it was actually Galileo who first proposed the theory of relativity, not Einstein. Einstein’s addition was introducing a finite maximum speed, which is known as the speed of light. Lorentz(who is famous for the Lorentz force law of electromagnetism) actually arrived at the mathematic used to describe this finite speed of light a few years before Einstein, by considering Maxwell’s equations, and how changing reference frame would affect Maxwell’s equations. Einstein did invent the theory of General Relativity, which introduces gravity as space time curvature.
its crazy how many things in physics are so closely related despite being 100s of year apart
galelio was very close to being correct, but since the laws of em werent discovered yet he couldnt finalize it
Shoutout to the orange box. One of the best deals in gaming of all time.
Absolutely
i enjoyed this analysis, but it did bring up one more question about the moving portal and stationary object: lets say you have the box sitting on a table, and the portal is being lowered onto the table from above, but the other end of the portal is also on the roof, so he box will come out falling. at some point, there should hypothetically be more of the box on the other side of the portal, and therefore the gravity on the other side should suck the rest of the box through, even though it is stationary on the other side. but that also means that in theory, there should be an equilibrium point where you could remove the table, and the box would stay suspended in the portal being pulled both ways.
i'm not sure if this understanding is correct however
What a fascinating concept! That seems accurate. The precision required to get it EXACTLY half and half would be worse than balancing a bowling ball on a tightrope, but it’s theoretically possible.
yep!@ it should be possible to float the box in this fashion. but in practice it would be infinitely difficult, like trying to levitate a nail between two magnets.
Also made more complicated because of the momentum of the box going through a portal (so it would favor going through).
3:13 technically incorrect for when we pass a laser to break off pipes to the neurotoxin is the only time we see moving petals!
Of you’re right, I totally forgot about that!
@@TheChiptidein the 2nd game there's a command to turn on the ability to have moving portals but it doesent work to well
this could be used to justify the idea that the portals just don't need to be accelerating relative to each other.
....until one puts into account that putting a portal on *the moon* worked. so really i guess we should just assume we can't put portals on moving surfaces for gameplay reasons
My understanding of moving portals:
They cannot exist because quantum tunneling requires an absurdly low temperature (4 Kelvin). Movement is directly tied to temperature; The hotter something is, faster it moves (on the atomic scale at least).
Oh, that’s actually super interesting, I hadn’t thought about that but you’re right!
Low temperature does not prevent motion in any way.
I can throw a hot or a cold ball at you and it’s not going to magically slow down or speed up.
Temperature is related to the chaotic motion of particles around their equilibrium point inside the substance.
It’s more analogous to a spring. If I stretch a spring in zero-gravity, it will contract and expand in place for a long time.
Now, let’s say the spring has low energy, i.e. its parts do not move a lot. This does not prevent it from moving as a whole, since the stored energy is related to its displacement from equilibrium, and not from its starting position in space.
Similarly, even if a portal requires low temperatures, it can still move as a single solid object with any speed it likes.
@@fullfungo I am nit so sure whrn you want to have very cold particles you need to cool them down
@@MozzarellaWizard @TheChiptide the quantum tunnelling theory is unconvincing to me unless particles are somehow entangled or something between both sides of the portals, but really all quantum tunnelling will do is allow an electron to phase through another particle. It just doesnt seem to map onto the characteristics of the portals in the game because it seems to work on a much larger scale than electrons and does more than just let you phase through walls. It doesn't satisfy my brain as being a possible theory.
Also I recommend looking into internal energy again if its been a while since you've done physics, because you cant really compare movement on a macroscopic scale and subatomic scale. Thermal energy is the total energy of every particle in an object, but thats the random disordered motion of molecules. It doesn't typically interact or transfer in some way to become kinetic energy. Its quite hard to fully explain these differences without writing an essay, but the difference is essentially that this thermal energy is the *disordered* movement, whilst on a macro scale kinetic energy is the *ordered* movement of particles. It doesn't transfer back to kinetic energy (unless you count gases but they act differently to solids and liquids).
@@spate7207the game does explicitly state on some signs in old aperture that it's a quantum tunneling thing tho iirc
Accidently dropping the companion cube between portals as the infinitly sharp edge splits an atom apart causeing a hudge explosion as it rips proton from proton.
splitting atoms doesn't cause an explosion. nukes work on the basis of a chain reaction; the energy from splitting a single atom is enough to split multiple atoms. thus in a very short period all the uranium or whatever the fissile material is is then all split; all those like. >> 10^23 or so atoms splitting practically simultaneously releases extreme amounts of energy and causes the explosion
like the other response said, nukes work off of chain reactions, not splitting a single atom
but also
theres *so* much more space in an atom not being taken up by the nucleus than there is being taken up by the nucleus, that the event of this plane cutting through one of them is actually incredibly unlikely, as this plane would have to line up exactly with one of them
@@ottertvmtg6229 I know, but this is a joke. I did it to be funny
Easiest way to explain the portals is = a set of portals is like a open door and can be used as such;
Just have one side of the door being in one spot and the other side is somewhere else and there you go, a portal.
Here's a paradox that I'm curious about. When you have two portals, one at a low altitude and one at a high one, and move an object from the lower one to the higher one, gravitational potential energy is gained. But no other forms of energy is lost- and energy is produced out of nothing. Inversely moving an object from a higher place to a lower place results in a loss of GPE. I know this can be shortcutted and have something to do with energy stored in the portal or portal gun itself, but is there a more satisfying answer?
If the portal doesn't need energy to maintain itself, then yes, it breaks the law of conservation of energy and can therefore be used to produce infinite amounts of it.
Though what's more plausible is that the portal would require immense amounts of energy to maintain, enough to balance out the energy change of anything going through it, positive or negative. That would mean that if you could store the energy from a portal, you could do the opposite and shortcut a waterfall or something to produce high amounts of energy that way, not dissimilar to a water wheel
Here’s one idea.
Gravitational potential energy isn’t magic. It’s calculated based on the, well… gravitational potential. For any given path the object takes, you can integrate the gravitational field to get the total energy it takes/produces.
However, the portals simply connect distant points in space. So the gravity will “leak” through them, i.e. objects next to one portal will experience the gravitational field on the other side of the portal. This will result in a very unusual shape of the gravitational field.
Now here comes the speculation part. It might be the case that the changes to the gravitational field will be such that integrating over any loop that goes via the portals will still result in a positive amount of energy required to complete that path.
This requires some calculations to verify, and I’m too lazy for that😅
@@ehmareeeasiest solution I can figure is that portal energy consumption increases with the amount of energy required to move an object through it. So objects going through a pair of portals from low ground to high ground would result in higher energy consumption, from high ground to low ground would result in baseline energy consumption.
@@fullfungothat would stop infinite fall loops tho..
@@zacknattack Infinite fall loops _should_ be stopped.
As someone with almost 1000 hours in portal, and well over 5,000 in portal 2, I 100% understand it being your favourite game, ever. It's nice to see a fellow enthusiast, everyone seems to not care nowadays.
Here's a question I have: moving portals a re fun, but what about portals of different sizes? what if you had a blue portal the size of jupiter, and an orange portal the size of a door? as the atoms get bigger and smaller, I imagine a lot of very interesting nuclear physics would occur. But how? what are the ramifications? and which is less dangerous, making a small thing big, or making a big thing small?
Now, what if you took the orange portal, put it in a box, and pushed the box THROUGH the blue portal, and then walked through a fizzler? where does the box go?
That's got me curious: what you could you possibly do for 1000 hours in 5-hour'ish puzzle game?
@@laierr we just sit there and glare at eachother until one of us drops dead
@@laierr but all joking aside lol, a lot of testing. there's always the community chambers, but there's also the main story, which not only is fun to run through, but also has fun puzzles, and interesting locations to explore. And you can always mix it up! Try to do chambers faster, try to do them with fewer portals, do them in VR, do them just because you can, etc. And there's hammer - make your own maps! It's tough to get right, but learning it is relatively easy, the tutorials are old though. but once you get the hang of it it's not so bad. Except for when it is. But I block those from my memory lol
@@Anklejbiter thanks. it's always fascinating to me, how people could make hobbies out of everything and build whole communities around it.
My favorite paradox in the video is actually the thumbnail. It'd be impossible for both of his hands to be behind his other hand
I would like to see a part 2 on the portal 2 gels and how they would interact with various objects. Including OTHER liquids which portal 2 I dont think did much with.
Let's just assume that Portal has some weird crossover with FNAF Into the Pit and Oswald owns a Portalgun.
What would happen if Oswald places a portal in the past and a portal in the present?
Interesting thought!
I think they’d theoretically work just fine, real wormholes work by folding space-time, meaning you could use them to travel through time just as easily as space!
Going through the pit removes all portals like the barriers at the end of the tests
well iirc the pit actually just transports you to a memory, so nothing done there actually influences the causality of the real world, only the psyche of the restless spirits inhabiting it, and idk if the other side even has "space" in the same way our world has.
It would just be a more accessible pit i guess
6:45 small correction: the speed in is -10 out is 10, so you should add an absolute aka |Sin(c)-Sin(p)|=|Sout(c)-Sout(p)|
12:44 correct no2:well its fa×ma=fcut so its the classic question of 0×inf=? But if we said that you know cuz inf is not a number instead its a huge number(i guess undefined is also something cuz L/0=n/0) still no force is 0×n=0 so no you do still need force even if extremely low force needed
Yeah, I suppose it would have been more accurate to say “Velocity” as opposed to speed, where direction matters
I was expecting to see a reference to the "crushed between two portals experiment" video in the pipe section of the video, but I can extrapolate from your explanation that anything put between two portals that are moving towards each other would be simply crushed by itself, pretty much like the pipe being tensioned by itself by two portals moving away from each other. Is that right?
I'm curious if the portal to the moon was left open would the earth's atmosphere all eventually equalise with the moons? does the moon have enough gravity to support that? How long do you think it would take to completely drain the earth's atmosphere?
So portals already violate conservation of energy and momentum.
The rod example is a weird one to think about, mainly cause we don't have true knowledge of how the portal acts. Would the act of pulling cause an energy strain on the portals due to the rod being a reference fixed reference point between them? Would the fixed portal size immediately collapse under this strain, or will the portal size shrink relative to how much force is applied to the portals until the portals collapse? Or will it happen as you described with the rod failing first?
personally i feel like the rod thing would happen; if i tried to pull the surface the portal is on with my bare hands, i think it would feel like i'm pulling a steel rod attached to a wall
edit: and if the other portal is also on something loose and movable i think pulling one object the portal is on would just move the other object to keep the distance fixed
7:13 So if a portal is slamming down on you at like 10m/s would you get a concusion? or neck injury as your head is briefly moving at 10m/s relative to your body? Or does the portal catch up fast enough? what uf there were concrete blocks either side of you that suddenly stopped the portal at neck height?
10:03 pretty sure it would snap where it was wielded, not where the portal laid
I would love to see a part two of this! can we get a Portal going through portal paradox answer?
minutephysics actually made a pretty well-made video on this.
4:25 I don't think you even need einstein to prove that the block will move cause when you think about it, for the block to come out of a stationary portal when it's going inot a moving one, it would need to "make space" for the rest of the cube. Because if it didn't move while coming out it would get smashed into superflat object as every thing is "placed" on top of each other
I probably butchered english, but I hope it's still understandable
Every time I take notice of your subscriber count, I always feel like you should have more, you definitely make higher quality videos than other channels with so many more subscribers
About the first question, i always answered it without thinking with the same reasoning as in this video, BUT now that i actually think about it wouldn't it break the сonservation of energy? The box didnt have any mechanical energy to start with and than he gain same amount of it from thin air.
@A9to I think the big issue I have is that the portals are just acting as a hole in reality to bridge 2 points, so how is the portal moving even supposed to impart the energy to the cube?
@SilvrSavior it doesn't. People who think that the cube would have momentum are missing the big picture.
The real portal paradox is why my doctor requires me to enter a portal to get in touch with them. Girl fck your portal let me call you
Posts from the fae realm
Real
And what if you put a portal exactly were another one is ?
- Parallel : It would be as if there was no portal, an object would pass through the first and the second portal without diverging (maybe we live in a universe with infinite portals stacked in this way everywhere, we'll never know)
- Parallel but mirrored : Then nothing could pass through it, as any particles would be pushed away by themselves (this would be the strongest barrier of all times)
I honestly always assumed and thought the moon thing had something to do with the pressure difference/the vacuum of space
- Also, is it just me or can you actually see something visualizing seemingly air currents in the ending cut scene?!
When you said the portal would cut your hand off that would only be true if the portal is also very very durable because if you have something as thin as an atom in real life, you would just break it by applying any pressure
Just like the world's sharpest blade (only an atom wide) can't cut anything, the 2D edge of portal couldn't either. Just like you see standing in between portals, you'll just hit the walls of objects you connect.
1. Portal A on wall vertically
2. Portal B on oval shaped table
3. Rotate table and pass it through portal A
8:28
With the 1-Meter Pole thought experiment, you're omitting the fact the portal you pull away from the other would have to pass THROUGH the BACK of the other portal in order to move further than 1 meter away from the FRONT of the other portal.
So the REAL question here should be:
What would happen if you moved the orange portal THROUGH the blue portal?
Instant implosion of all of reality, perhaps?
That's what is theorized in my science-fiction novel, anyhow.
What does @TheChiptide think about this?
If I understood it well you are asking for the oposite right? I guess it would compress
@@Dario-uj6qo No.
If the 1-meter pole is going through both portals,
you can only move the orange one 1 meter away from the blue portal before the orange portal would have to exit the blue portal.
Presumably, the pole would stay intact and simply fall down in front of the blue portal,
but that's ignoring whatever would happen if the orange portal were to exit the blue portal.
Since they're both opposite ends of the same "wormhole",
what would happen if one end came OUT of the other or went INTO the other, is what I was proposing.
Rick roll isn't old! It's not.. old.., it's not
The easiest way to explain the moving portal paradox is that if the speed were to stay zero then the moment it passed through the portal the cube would become stuck since, in order for the rest of the cube to pass through, the initial part of the cube needs to move out of the way.
I thought that last one was fairly obvious, just hearing the wind in the game, but the other answers are pretty interesting for sure
What if you took a portal and put it on a piece of concrete and broke the concrete in half?
The amount of possibilities portals have simply in the scenario of one in each side of a person is insane, what if i reach into the portal and pull my self up from my ankles? What if I tie a rope with itself through the portal?
Keep in mind that gravity still exists. You can't lift yourself up using a portal any more than you can lift yourself up without a portal.
oh no that portal radio music is giving me flash backs
“gonna do some push-ups”
The "moving portal paradox" is easily resolved if we interpret the rule "you can't place a portal on a moving surface" as "portals can't move relative to each other," ensuring momentum is always conserved. While the in-game scene where a portal cuts neurotoxin pipes breaks this rule, we can give Valve a pass for that one.
I'd love for you to extend on that whole gravity thing tho! Cause, like, if there is a portal on Luna and one on Earth, both on the floor of their respective celestial bodies, how WOULD gravity act tho? Would there be a semi sphere of approximately 1g around the portal on Luna and a semi sphere of less than 1g around the portal on Earth?
From what we see of portals, the implication is that gravity doesn't "go through" portals at all. Objects seem to be affected by gravity separately on each side of the portal. So if something was placed halfway through the Moon-Earth portal, one half of it would be experiencing Moon gravity pulling it down into the portal, and the other half would be experiencing Earth gravity pulling it down into the portal. The result would be the object being pushed through to the Moon side. But if the object were entirely on one side or the other, it would only experience the gravity from that side of the portal. For instance, an object that was placed right next to the portal, but not entering it, on the Earth side of the portal, would only be experiencing Earth's gravity.
I loved this video! I'm so glad I subbed to your channel, because every video of yours that I've watched so far has been amazing. Also, I always thought that the atmospheric pressure vacuum thingy for the moon shot was obvious, but I guess I just have to remember that not everyone has the same knowledge base (I was obsessed with space as a kid). Thank you for explaining these concepts in a way that is both understandable to newbies and not patronizing to experts. :D
Some part of my soul needs the level of stretching that would come from grabbing both of my own hands through two portals.
Paradox 2: you can't guarantee the bar will break at the portal, all those forces add tension to the whole bar. The weakest point of the bar will most likely break first and that is probably the weld.
Paradox 3: in the game you can stand on the bottom of two portals in walls. Therefore we must conclude the glowing aura exerts a force away from the infinitely thin edge strong enough to support your weight. So you would need more then 0 force to cut yourself.
Paradox 2 is solved right the thing is that we specifically trying to break the point touching the portal. We apply force to the same point, cause it is just in the portal therefor the mechanical tension is not experienced by the rest of the rod.
@@СачкоАртемОлегович You are not understanding how tension works, he points out how the red segment is being pulled in both directions but the thing is every segment is being pulled in two directions. In the tensile strength test that is called out as being an "identical setup" the portal is the two ends of the test rig so the red segment is the ends of the sample, note in the tensile strength test video the bar did not snap at the ends where the force is applied but ~60% of the way up. There is a difference in the test shown, the sample flairs out at the ends making those the thickest part and not the point of failure. If you ignore the weld and say you forge the bar into one piece then the braking point is determined by the grain of the metal, that is the molecular arrangement of the atoms! There will be slight variance of strength throughout the bar and the weakest point will fail under tension first. Grain is the areas where the metal is in the same crystal formation & orientation, larger grains can slip past each other easier then small ones so a region of the bar with larger then average grain size is where the bar will fail.
1. No real argument.
2. Now, the real question would be if any force would get applied to the portal or its surface itself.
3. Wait, even if it has infinitely small thickness, why would it have any length at all either? What material is providing the length in this case?
4. Wait, that’s obvious. Who thought it was gravity?
To my understanding the edge isn't infinitely small, but in fact 0, so it's an undefined property. Like they mentioned in the video, a proper portal would be a sphere. So at this point you try to have a 2 Dimensional object in a 3 Dimensional space, wich just doesn't work out.
Sin and Sout is the best duo. Change my mind
Scubein, Sportalin, Scubeout, and Sportalout are way better
Gravity and portals are actually a really interesting concept. For the sake of gameplay you're only affected when you pass through the portal even though it seems like there'd be a whole extra earth's worth of gravitational pull.
"Falling up" me: *(visible confusion)*
The thing about opening a hole from the atmosphere into vacuum is, nobody ever gets its right, to how fast the air moves and the force of the now lower pressure air close to the hole.
This is to an extend some people think we would get sucked through a small hole instead of recognizing we could plug it with a single finger or the palm of your hand.
Did I just get rickrolled in a portal science breakdown video
The idea that all motion is relative dates back to Galileo, and is called Galilean Invariance. Newtonian physics agrees with that. The problem is Maxwell's laws do not, and show that electromagnetic waves travel at a constant speed. Einstein figured out that that can be relative too, and if moving changes not only your idea of where something is, but when something is, it can cancel out, and you'll disagree on how far a photon travelled, how long it took, and even whether or not the clocks at the start and end were synchronized, but you'll still end up agreeing on how fast it's going.
The rod wouldn't necessarily break at the plane of the portal. That's no different from any other plane. It could just as easily break at any point.
The portal wouldn't be a perfect edge that can cut anything. It would certainly seem like it from our perspective, but if you have molecules or atoms hitting it, they wouldn't necessarily cut. After all, separating them means adding potential energy, and if there's not enough kinetic energy to do that, it won't work. Whatever electric fields they have extend out into 3d space, and can wrap around the portal's edge.
I agree with the portal to the moon, part, but I think it's worth noting that you don't have to make a portal all the way to the moon to get a difference in pressure. Just opening one portal above another would do it. Not enough to pull you in, but I think it would still be a pretty noticeable wind.
Another fun one is when you realize that time will at different rates for a portal on Earth vs one on the moon. The plane of the portal isn't fundamentally different from other spacetime. If you have a clock on each side of it, they'll show time passing at the same speed through the portal. Which means that if you wait long enough, the portals have to be sort of out of sync with time. Eventually, you'll have a portal to the past. And if you bring it back, you'll have a time machine. Incidentally, this means if the portal was shot at the speed of light to the moon, there would be no delay for it to open. Sure it takes a few seconds for the portal to get there, but from the portal's point of view, it's instant. But that doesn't mean the game was wrong. Just that the portal wasn't traveling quite that fast.
Combining the ideas of how cubes behave moving through portals and how the pole behaves when held in tension between portals, I'm curious how much a malleable object can be distorted by a moving portal or how much spin would be imparted on a non-malleable portal through moving portals.
Just want to say that since I followed your channel I've found a few other channels that try to explain silly video game logic with science, and while I didn't think any of them were bad, your videos are by far the ones that make all the math understandable the most, while also having a really great sense of humor. Hope you get to keep doing this channel for a good while!
The first case can be easily explained: if we consider "speed" as the time it takes the block and the portal to connect with each other, it doesn't really matter if it's the block or the portal that is moving.
Brilliant! this is the analysis I expected and did not get from 60 symbols!
I just have to say this is very high production value for a smaller(not small 27k is still a lot) creator. some bigger creators should take an example on this damn so good.
I had a moment during this when you explained how a portal would have to be spherical.
The reason it clicked in my head was because you said the space between portals would have to be infinitely thin, which just doesn't compute.
Then I began thinking about what a spherical portal would look like and how we would even interface with it?
So me being me I just dropped the amount of dimensions to think about it in because obviously 2D portals are my specialty lol.
when doing that I realized there could be a chance that 2 dimensional beings would have a similar question to the one I've posed above, leading me to believe that only 4 dimensional beings could imagine a way for us 3 dimensional being to interact with a 3 dimensional portal.
Fun video!
I'm surprised this needed to be a video. That said, put a beam of light between two portals and see if you can break light or move so fast that light becomes a solid
I love this channel because I almost flunked high school physics and barely understand half of whats being said but then it's put in the context of a video game and suddenly I can almost comprehend it lol
Also how can a meme be truly "dead" if it is being used and enjoyed? 🧐 A meme can only die if it is forgitten. As long as we use them, they are immortal 😌
Regarding the first one, an easier way to think about it is this: Any object that travels into one portal regardless of whether the object is moving or the portal is moving isn't going to exit out of the other portal all at once. The part of the object to touch the portal first is going to exit the other portal first. So if you have an object sitting motionless and a portal rushes towards it, the object is going to gradually exit the other portal at the same speed the moving portal is moving.
Another way of thinking about it is that movement in general is preserved by portals. If the exit portal isn't moving and the object isn't moving but the entry portal is moving, that motion needs to be preserved somehow, so it is transferred from the entry portal to the object as it exits the exit portal, giving it motion.
The implications of this are pretty scary though. The more dense and massive something is, the more difficult it is to bring it from rest into motion, let alone reach high velocity. It would seem however that this is done quite easily by simply accelerating an entry portal towards such an object. Regardless of the dense and mass, it should always eject out of the exit portal at the same speed as the entry portal's motion as it passes through it. The only solution to this I can think of is that the entry portal should actually lose speed proportional to the mass and density of the object passing through it to properly convert stationary energy into kinetic energy. As such, if the entry portal doesn't have enough energy to transfer into the object it should actually stop partway through the process of passing the object through it. Likewise, objects wouldn't eject out of the exit portal at the initial speed of the entry portal. The portal would slow down depending on the mass and density of the object the moment the object started to pass through, which would result in the object's ejection speed being proportional to the now slowed down speed of the entry portal.
Like the video only one thing I don’t agree with. Regarding the portal’s edge, there should not be an edge in the first place. A portal isn’t infinitely thin because there is no actual mass to the portal (best way to explain it) or there is no inside to it. If the portal has no space inside of it, which it shouldn’t have, then the portal would not slice your hand. Instead, I’d assume it’d be impossible to push passed it, thus, meaning it could not cut anything. Sorry if that explanation was hard to understand.
Definitely not saying your idea is stupid since it seemed like a logically conclusion. I just had a little bit of a different idea and I might actually be wrong
A question I’d like to hear answered is what would happen if you put a portal into another portal or what would happen if you split the surface the portal is on
The two portals with a beam welded to itself becoming a tensile strength testing machine raises a lot of interesting questions, though. It implies that a force can be exerted on a portal (or, alternatively, on the surface it's placed on) by an object going through it. But momentum is conserved between portals, and therefore so is energy, so where does the force come from?
Your evaluation of the first paradox does not appear to be correct. Relativity actually supports that the cube would not exit the second portal with any velocity.
You must think of both portals as not two different portals, but two sides of the same portal.
On one side you have environment A, on the other side you have environment B.
The cube is only moving at a certain speed relative to one side of the portal, (moving relative to environment A.)
The moment it passes through, if you were standing at the exit (environment B) looking back into the portal, you would still see environment A getting further away, because the other side of the portal is moving.
in other words, the cube is still moving relative to environment A because the portal itself is moving. however, once it passes through to environment B, it will not have any velocity itself. (yes it is possible to not have any velocity but be moving relative to something else, in this case relative to environment A.)
once this happens it will be subject to local gravity of environment B and be pulled downward, but not have any forward momentum.
logically this has to be the case. if the cube exits the portal with the same velocity of the moving portal, then it's relative velocity to the previous reference frame would be double what it should be, since now both it is moving away from the portal, and the other side of the portal is moving away from it at the same speed.
THAT SAID, because portals break the laws of physics, they also can break the equations we typically use for relative velocity and such because it creates new edge cases that don't exist in our physical universe. Therefore, it is possible that if the programmers of portal did not account for this, then you may experience different results in game than would would actually be expected to occur. for example, they may have hard coded that object exit with the velocity they enter the portal with no matter what, without accounting for the possibility of a moving portal. In this case, then results may vary. I am merely explaining what should actually happen if it were programmed correctly.
This logic doesn't seem sound - you say that environment A would look like it is moving away, but it would actually look like it was moving *towards* you, since the portal is moving forward. If the cube were to stop, it would look like it suddenly went from moving towards you to sitting perfectly still, which wouldn't make any sense. Thus the cube *must* come out the other side moving.
good stuff looking forward to part 2
Regarding that last point, what I'm curious about is if the pressure difference between Earth and the Moon would actually create a strong enough aircurrent to actually escape the Moons gravity. The things being sucked through the portal would have to move at over 2 Kilometers per hour, otherwise they would just land on the moon somewhere
Cool thing about the ending of portal 2 with Wheatley in space floating. The speed of things sucked through the portal (pressurized to non pressurized) can reach speeds of 186000 mph and the moons escape velocity is o lot 18000 so it’s scientifically accurate he flew off instead of staying on the moon
16:04 little correction: the air isn't sucked into space, it's pushed. same thing with a hole in like the space station. the air is getting pushed out from the inside, not sucked out from the outside, as you showed with the ballon. but great video anyway!
You can not use mechanical advantage outside the classic physics and apply it to fields. When we are talking about really thin or infinitely thin edge. The length of the edge is also 0 in this case, which brings the contradiction. If we were to talk, about what would actually happen we must take into account general relativity and consider, what exactly will form on the edge of the portal.
3rd paradox: infinitely sharp edge
if you think about it in a micro scale, the shortest distance between two atoms that are being severed is increasing since the space is discontinuous around the portal edges. That should still require some force to do if only to satisfy the energy requirements
2nd paradox: infinite rod
this means that the portal experiences a force from the object as it resists being broken, which is interesting to me because the idea that a portal being influenced by the things that are passing through it isn't really present in any of the media I have seen.
also, all the fields including gravity get messed up with portals lol. though i guess that might be partly due to us looking at 2d portals in 3d space
In Portal 1 you flat-out can stand in a portal with no other ground (both ends of a portal on a wall well above a floor), and Portal 2 it tries to shunt you to a side if you try standing that way. Question 3 is thus answered in-game, but you *are* arguing about hypothetical portals so that's still a valid chunk of video. I think the wormhole does have a miniscule thickness, though, but I don't have a source for that.
A portal that's 8ft by 4ft would have a surface "area" of about 100.53 square ft, with 14.7 psi * 100.53 si, that's about 1477.8 pounds of air blasting Chell into oblivion in the moon scene
> set up two pool sized portals facing up
> pool but better
Bonus question: What about gravitational influence? If you place two portals on ceiling and stand below one - youll have a window to an entire earth above your head. What will happen with gravitational pull if you have earth below you and portal-window to the same earth above you? Would you experience zero gravity (equi pull up and down) while standing below\\close to those ceiling portals?
Bonus question 2: Place two portals facing one other. Stand between two portals and hold your right hand with your left hand thru the portal. Now pull left hand. Now start using legs to leverage against floor. You have force exerted by legs pushing you behind, force exerted (by your left hand in portal behind) on your right hand pulling you behind and you have force exerted on your left hand (by your right hand from portal in front fighting pull) pulling you forward. Will pulling forces be equivalent and you just push yourself by legs behind, or there will be some unexpected interraction?
For the first question:
Gravity doesn't seem to travel through portals at all, so until you actually started to move between the portals, you wouldn't feel anything.
The force in each direction would change depending on how much of you was on either side of the portals. If you put your hand through one of the portals, *only* your hand would be experiencing the gravity pulling it down.
Because of this, while you could experience zero gravity if you were placed *perfectly*, the more likely outcome is that you would be pulled more from one side than the other, which would pull you more in that direction continuously until you popped out that side of the portal.
For the second question:
Pulling your left hand with your right hand through a portal would feel exactly the same as pulling your left hand with your right hand *without* a portal (you can try it out right now). There wouldn't be any new interactions here.
i would posture a different hypothesis with the pole between two portals.
you see as you move the portals apart, it's not just the pole that gets stretched, it's the space between the two portals getting stretched, stretching and warping space like that would be impossible for any possible machine to accomplish, either the mechanism can't generate the force necessary to move the portals by a significant amount or the force required would just destroy the mechanism entirely in a way to how you can't swing an infinitely long pole to make the tip move faster than light, the amount of energy needed to move the pole at all would not be possible to achieve and if it were possible to provide that much energy, the pole would just snap.
also interesting fact: while there are moving portals in portal 2, the motion is always perpendicular to the direction the portal is facing (left, right, up, or down).
I want to ask instead about the blue gel?
(Others are mentioned already or clear: orange reduces friction and white is moonrock grinded)
isnt that the bouncy stuff or is the bouncy stuff purple
@@xaigamer3129 it is the bouncy stuff don't know what you mean by purple tho, I remember only: blue (jump), orange(speed) and white (ground moon dust for portal placement)
Congrats for the 27K and, by the way your videos are really high quality hope you get to a 100K soon
Another question about gravity, shouldn’t infinite falling be impossible? You need 2 portals facing each other perpendicular to the ground. The object being dropped is getting pulled by the earth so it falls down and passes through the portal. Now the earth is pulling it from below and above through the portal.
The bottom portal is slightly closer to earth meaning the gravitational pull out of the top portal is slightly stronger than the earth is pulling the object as it exists the top portal.
Maybe didn’t explain this well but the end result is the object floating slightly passing through the portals.
Not to be too nerdy but your planet was turning backwards.
What I don't like about the first scenario is the fact that the box has to have an infinitly high acceleration the moment the moving portal "touches" the box.
Besides that: if the box shoots out of the other portal, the relative speeds change when crossing the portal.
You got a moving portal, a still portal and a still box. Let's say the relative speed between the moving portal and the box is 10m/s. The relative speed betwenn the other portal and the box is obviously 0 m/s. When the moving portal approaches the box, the relative speed between the box and the portals change immediately. As the box shoots out of the still portal, the relative speed between the still portal and the box is 10 m/s.
I was wondering if you were going to get the air pressure vs gravity at the end. Never thought about it but now you mention it no one wants to trip goingthru the portal. I just want a portal gun for intereting things like moving the people blocking the aisle into the parking lot or something.
Thank you [UA-camr name here] for such such an amazing video!
As an aperture representative i should say that it helped developing aperture science handheld portal device safety protocols
You must be the pride of [UA-camr hometown here]!
Thats truly unbelievable!
If you apply for a job at aperture you'll get a cake of your choice* for free*!
Please read our definition for the terms "of your choice" and "free"
The first problem has a much more intuitive solution.
If portal "consumes" an object with a certain length at a time, the object should appear from the other portal with the same length at a time. And (Length) * (Time) is a definition of speed. If it has speed of 0 relative to exit, it cannot exit. Therefore it cannot enter. Because you obviously should have the velocity to exit the portal. V(in) should be equal to V(out).
If we have a meter-long rod and portal moving towards it at 10cm/s, it should disappear in the portal within 10 seconds. And it has 10 seconds to appear on the other side. So it should appear with a speed of 10cm/s relative to the stationary portal.
i'd argue that the edge of the portal needs a nonzero force to cut. when the edge of a blade is thinner than the gap between molecules, it doesn't matter if it gets thinner than that. it has reached the minimum number of intermolecular bonds it has to break. and that number isn't zero. you have to input energy to break those bonds by applying force.
if it was an actual zero width blade, btw, i don't think it would cut at all. molecules either side of the blade would remain close enough to still have their interaction.
Two portals, facing each other, in a vacuum. A box in between them.
Move the blue portal through the box, so it shoots out the orange portal (now moving toward the blue one). Before the box reaches the blue portal, move the blue portal back to its starting point, and then again toward the box.
The box now has twice as much speed. Repeat this process.
Can you accelerate the box to the speed of light in this way?
This can be made even more complicated when we consider the speed of photons passing through the portals. In which, moving a portal should be breaking physics, yeah? Maybe moving one should actually move both of them?
To simplify the last problem basically chell basically turned the moon into a earth powered air rocket. Honestly considering what I've heard going on in deep ocean oil rigs I'm surprised chells arm isn't ripped off I'm kinda curious how much thrust that portal is shooting at chell and Wheatley.
If you haven't already would love a video about time dilation and how it doesn't exist. Example the light in an atomic clock moves a greater distance the faster the satellite goes that makes the clock tick slower because it takes longer for the light to catch up to the satellite. Not time dilation.
The 1 metre pole between portals, if you try to pull the portals apart, how are they physically interacting with the pole to try to stretch it? Assuming the pole is kept suspended in the middle of the portal (let's say with magnets for arguments sake), how is the force applied to moving the portal transferred to the pole?
for the third question if it was infinitely thin it would mean L/0 which is undefined so unless we define it as infinity a 2d portal would be impossible
and we cant just define x/0 as infinity because it would also be infinity in the negative direction
If we accept the moving portal solution from the video, then moving a portal requires as much energy as anything going through it gains kinetic energy
the moon one is super simple, you went it with x velocity, and then popped out on the moon still with that velocity, with very little gravity to pole back, and hardly any atmosphere to bounce off of, so yeah you're gonna keep going shooting out into the void of space, the moon will pull you back down eventually (assuming you didn't enter with escape velocity) but it will be a bit, like shooting a rocket into the sky and waiting for it to fall back down, but now with the moons low gravity
If portals are mathematically possible, couldn't a computer simulation show how they'd work if they were also physically possible?
10:57 while not visible in the game portals do actually have a solid edge of approximately 0.1 inches
You make two portals on the floor, you go in with 0 horizontal momentum.
I think you keep moving up and down till the pressure on your body on both portals are equal
4:21 Albert Einstein isn't suggesting that, Descartes is suggesting that.
Special relativity explicitly has to do with speeds relative to the constant speed of light in all reference frames.
But the Cartesian frame of reference was popularized by Descartes.
I LOVE THE CAKE!! AND THE VIDEO!! AWESOME THANK U!!!!!
For the first one, I’ve always imagined it as literally just a moving door. Yeah, there’s a chance the gravity can be different on the other side, but if you just had a moving wall (assuming it’s not a portal) fly around a cube and nothing happens, why should anything happen with portals? They are intended to be quite literally just doors
Basically, the room is moving around the cube, wether it’s a weird worm hole or not
16:05 is not gravity, but it is pressure, so it is gravity. Making the surrounding air push you through the portal. In fact vaccum don't suck, heavy air push.
The only one I disagree with is the 3rd one. Yes an infinitely thin edge would slice, if it was actually an edge. But it's infinitely thing in both directions, the length in the equation is also practically zero and seeing as 0/0 is completely undefined I think it's just up to everyones own head canon, mine being that it would take on the properties of whatever the portal is on, usually a solid surface that you wouldn't be able to cut anything with
Personally, I didn't need this formula to answer this question. In fact, I think that formula isn't applicable to this situation at all. A plane that has no charge and is thin enough to pass in-between the atoms of your body would do just that. That's what neutrino do all the time (except, they are like points, not planes). The problem with the plane of the portal passing in-between your atoms is that now one of those atoms is here, and its neighbor is over there on the other side of the room. It wasn't a problem when a portal allowed for passage of matter and force interaction, but now there's no portal connecting the base of your arm and its end.
@@ghurcbghurcb I mostly agree, I was just showing that even if you tried to use the formula it wouldn't be applicable. The only way our ideas differ is that you head canon that it would have a similar effect to slicing, but not technically slicing anything, while I'd rather go with what the game seems to show, that being that you can't move through the side of the portal and it just seems to act like the wall that it's on