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 This is a representation of your brain . And your brain can be broken into two parts . There 's the left half , which is the logical side , and then the right half , which is the intuitive . And so if we had a scale to measure the aptitude of each hemisphere , then we can plot our brain . And for example , this would be somebody who 's completely logical . This would be someone who 's entirely intuitive . So where would you put your brain on this scale ? Some of us may have opted for one of these extremes , but I think for most people in the audience , your brain is something like this -- with a high aptitude in both hemispheres at the same time . It 's not like they 're mutually exclusive or anything . You can be logical and intuitive . And so I consider myself one of these people , along with most of the other experimental quantum physicists , who need a good deal of logic to string together these complex ideas . But at the same time , we need a good deal of intuition to actually make the experiments work . How do we develop this intuition ? Well we like to play with stuff . So we go out and play with it , and then we see how it acts . And then we develop our intuition from there . And really you do the same thing . So some intuition that you may have developed over the years is that one thing is only in one place at a time . I mean , it can sound weird to think about one thing being in two different places at the same time , but you were n't born with this notion , you developed it . And I remember watching a kid playing on a car stop . He was just a toddler and he was n't very good at it , and he kept falling over . But I bet playing with this car stop taught him a really valuable lesson , and that 's that large things do n't let you get right past them , and that they stay in one place . And so this is a great conceptual model to have of the world , unless you 're a particle physicist . It 'd be a terrible model for a particle physicist , because they do n't play with car stops , they play with these little weird particles . And when they play with their particles , they find they do all sorts of really weird things -- like they can fly right through walls , or they can be in two different places at the same time . And so they wrote down all these observations , and they called it the theory of quantum mechanics . And so that 's where physics was at a few years ago ; you needed quantum mechanics to describe little , tiny particles . But you did n't need it to describe the large , everyday objects around us . This did n't really sit well with my intuition , and maybe it 's just because I do n't play with particles very often . Well , I play with them sometimes , but not very often . And I 've never seen them . I mean , nobody 's ever seen a particle . But it did n't sit well with my logical side either . Because if everything is made up of little particles and all the little particles follow quantum mechanics , then should n't everything just follow quantum mechanics ? I do n't see any reason why it should n't . And so I 'd feel a lot better about the whole thing if we could somehow show that an everyday object also follows quantum mechanics . So a few years ago , I set off to do just that . So I made one . This is the first object that you can see that has been in a mechanical quantum superposition . So what we 're looking at here is a tiny computer chip . And you can sort of see this green dot right in the middle . And that 's this piece of metal I 'm going to be talking about in a minute . This is a photograph of the object . And here I 'll zoom-in a little bit . We 're looking right there in the center . And then here 's a really , really big close-up of the little piece of metal . So what we 're looking at is a little chunk of metal , and it 's shaped like a diving board , and it 's sticking out over a ledge . And so I made this thing in nearly the same way as you make a computer chip . I went into a clean room with a fresh silicon wafer , and then I just cranked away at all the big machines for about 100 hours . For the last stuff , I had to build my own machine -- to make this swimming pool-shaped hole underneath the device . This device has the ability to be in a quantum superposition , but it needs a little help to do it . Here , let me give you an analogy . You know how uncomfortable it is to be in a crowded elevator ? I mean , when I 'm in an elevator all alone , I do all sorts of weird things , but then other people get on board and I stop doing those things , because I do n't want to bother them , or , frankly , scare them . So quantum mechanics says that inanimate objects feel the same way . The fellow passengers for inanimate objects are not just people , but it 's also the light shining on it and the wind blowing past it and the heat of the room . And so we knew , if we wanted to see this piece of metal behave quantum mechanically , we 're going to have to kick out all the other passengers . And so that 's what we did . We turned off the lights , and then we put it in a vacuum and sucked out all the air , and then we cooled it down to just a fraction of a degree above absolute zero . Now , all alone in the elevator , the little chunk of metal is free to act however it wanted . And so we measured its motion . We found it was moving in really weird ways . Instead of just sitting perfectly still , it was vibrating . And the way it was vibrating was breathing something like this -- like expanding and contracting bellows . And by giving it a gentle nudge , we were able to make it both vibrate and not vibrate at the same time -- something that 's only allowed with quantum mechanics . So what I 'm telling you here is something truly fantastic . What does it mean for one thing to be both vibrating and not vibrating at the same time ? So let 's think about the atoms . So one case : all the trillions of atoms that make up that chunk of metal are sitting still and at the same time those same atoms are moving up and down . Now it 's only at precise times when they align . The rest of the time they 're delocalized . That means that every atom is in two different places at the same time , which in turn means the entire chunk of metal is in two different places . I think this is really cool . ( Laughter ) Really . ( Applause ) It was worth locking myself in a clean room to do this for all those years . Because , check this out , the difference in scale between a single atom and that chunk of metal is about the same as the difference between that chunk of metal and you . So if a single atom can be in two different places at the same time , that chunk of metal can be in two different places , then why not you ? I mean , this is just my logical side talking . So imagine if you 're in multiple places at the same time , what would that be like ? How would your consciousness handle your body being delocalized in space ? There 's one more part to the story . It 's when we warmed it up , and we turned on the lights and looked inside the box , we saw that the piece metal was still there in one piece . And so I had to develop this new intuition , that it seems like all the objects in the elevator are really just quantum objects just crammed into a tiny space . You hear a lot of talk about how quantum mechanics says that everything is all interconnected . Well , that 's not quite right ; it 's more than that , it 's deeper . It 's that those connections , your connections to all the things around you , literally define who you are . And that 's the profound weirdness of quantum mechanics . Thank you . ( Applause )