The very real magic of quantum mechanics | Adam Murphy | TEDxTallaght

I want all of you to do something for me I want you to take yourselves back to when you were kids and I want you to remember the Wonder and the are you felt the very first time you saw a magic show now let's all get a little bit older and remember the disappointment you felt when you realized it was all a trick just a mirror or a particularly bendy lady the moment you realized that you were never getting your Hogwarts acceptance letter basically when you realize the rabbit was in the Hat the whole time it took me 20 years to find that Wonder again 20 years to find that curiosity but eventually I did eventually I found real magic to find the source of this real magic we have to go all the way back all the way to the early 20th century at that stage if you chose to do physics you are insane if you want to make your parents proud you became an engineer physics was done dusted over with the fat lady was warming up the vocal cords even Lord Kelvin the man who came up with everything we know in thermal physics the man who coined the word thermodynamics is attributed as having said there is nothing new to discover in physics you have to admire the arrogance of that but eventually a few new people came along men like Verner Heisenberg and Irvin Schrodinger they were real wizards and what they came up with changed the world as we knew it it turned everything upside down what they came up with was quantum mechanics and I'd like to use the magic that you all know to explain the real magic that these men came up with so let's talk quantum entanglement say I took a rabbit and I put it in the Hat but in with the rabbit I put a vial of poison that has a 50/50 chance of going off equally likely that it will or it won't the second I put the rabbit down so now it may have killed the rabbit it may not both are equally likely quantum physics says that since we can't know both solutions are equally valid the rabbit is not alive or dead according to quantum physics Robert is alive and dead at the same time so with a hotner rabbit I've created a zombie bunny but it gets crazier than that again say we add to this situation another rabbit and another hat and we put this rabbit in this hat and we put another jar of poison in with this rabbit too but this one has one slightly different rule it has to be the exact opposite of whatever goes on in there if that one goes off this one doesn't if that one doesn't go off this one does so we'll put this one down here so now in this Hut we have under hat we have two rabbits that are dead and alive at the same time but they have to be opposite if he's dead then he's alive if he's alive then he's dead let's they've been in those hats long enough let's see how they're getting on so we take him out and he's fine he's grand the bunny lives it's all wonderful except because they have to be opposite the moment I've seen that this rabbits alive that one has to be dead and I have to be a horrible bunny murderer but despite the rampant animal cruelty something wonderful has still happened here when I found out that he's alive that one instantly becomes dead it wouldn't matter if I was on the other side of the stage it wouldn't matter if I was back home in Kulak it wouldn't matter if I was on the other side of the universe the moment I see that this one is alive this one is immediately instantly dead that sounds incredible on its own but when you think of life light is the fastest thing in the universe nothing can travel faster than light from light takes eight minutes to get from the Sun to us but if I was at the Sun with one of these rabbits two things will have happened one I'll be on fire and two when I see that that rabbit is alive that one will instantly become dead eight minutes faster than the light can get from there instantaneously that's incredible it also lets you wonder what else is the universe is connected what other two things are connected with these entanglement sudden changes Einstein hated this he called it spooky action at a distance and it was an Irishman called John Stuart Bell a man from Belfast who proved it was true he proved this incredible real magic but we can go further down the rabbit hole specifically we can go down Alice's rabbit hole quantum physics is so insane so mental so constantly counterintuitive that we've had to start naming aspects of quantum physics after Alice in Wonderland characters so then we have the quantum Cheshire cat the Cheshire cat was famous because it could disappear and leave its grin behind that's what Alice said a cat without a grin is something I've seen but a grin without a cat is the most curious thing I've ever seen in my life so what if we could do that with objects what if we could take a bar of chocolate and take the taste away and in one hand have a chocolate bar and in the other have just some region of taste not connected to the chocolate bar or what if we could take a bright red ball and until we were done with it we could take its color away and in one hand have just a region of color and the other hand have the object until we were done with what we needed and covered them again to get our red ball again this was terrorized by a professor in tel-aviv in the 90s when he came up with it the general reaction was that's a lovely theory but please grown-ups are talking but it was proven earlier this year when a group managed to take a subatomic particle called a neutron and split it from its magnetic moment which is how susceptible it is to a magnetic field they actually did this they took they like took the color from a ball and that is also unbelievable real magic but the question there is this is all incredible this is all fascinating this is our magic but how does it apply to me it's all out there it's in a lab what if I told you you had this real magic in your pockets right now and that's called quantum tunneling say I took this rabbit and I hurled it into the audience I won't but say I did what would happen is the bunny would bounce off somebody because that's what happens objects pounds off things except they don't not all the time say I took a quantum particle say I took something like an electron something that makes up an atom and say I sent out at a barrier well there is a small but significant chance that that electron can just tunnel through ghosts through the particle like it like it didn't even see the wall like the wall wasn't even there it's not it doesn't tunnel through exactly that's kind of a misnomer it just ghosts through it just goes through it just is through to hell with your ideas of how walls are supposed to work now I said this was close it's in the Sun it's how nuclear fusion can happen to atoms in the Sun that shouldn't be able to find themselves inside one another can suddenly randomly total inside one another where they fuse and there they can give out heat and light so magic is there if you just look up but not directly up but I said it was close didn't I I said it was in your pockets everyone these days has a smartphone in their pockets and the flash drive the bit that lets you keep your videos your pictures your Miley Cyrus it's just start one song I promise well all of that is made possible through quantum tunneling a flash drive is made of a load of little components called transistor and usually transistors are just electronic switches but in a flash drive they're cupped with a little barrier that is so thick even electrons can't usually go through but say you want to write some data say you want something new on your phone well then you can give the electrons a bit of a kick and suddenly they can come in like a wrecking ball I mean I mean they know they now have they now have enough energy to travel inside the transistor where they get stuck and whether or not something is stuck besides your ones in your zeroes and your ones in your zeroes are what make up your word documents on your powerpoints your cat pictures and your selfies so just think of that when you log on to Facebook for the three millionth time today think of that real magic that exists in your phone think of that real magic that exists throughout the universe in the tiniest things in the biggest things at everything there is real magic permeating every aspect of the universe because it's my favorite thing about science is that magic tricks lose their luster the moment you understand how they work but science science only gets more impressive thank you very much

Channel: TEDx Talks

Views: 263,694

Rating: 4.7616582 out of 5

Keywords: South Dublin County Council, Quantum Physics, TEDx, Dublin, Physics, South Dublin Libraries, ted x, Quantum Enganglement, ted talks, tedx talk, ted talk, Spooky Action at a Distance, Slit experiment, ted, Quantum Mechanics, TEDxTallaght, Science and Magic, Schrodinger’s Cat, South Dublin, Einstein, tedx, Nano-science, tedx talks

Id: BHOzudE1oRk

Length: 9min 28sec (568 seconds)

Published: Thu Nov 06 2014

Reddit Comments

[u/Hello0897]

I dislike everything about this video, but he did a decent job of explaining the concepts.