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TEDx Talks
Published: 2011-11-28
Source: https://www.youtube.com/watch?v=wZzHnZzm_58
if yeah they just told me Baghdad at apparently there's a golden rule in book publishing it says that with every formula you show you lose half of your audience I have two in my first flight but I only wanna show you these formats to illustrate if if just a few symbols like F. eagles and times a we can describe a wealth of phenomena no from the
earth around the sun from a ballgame from your bike right everything or if your communication person you may like Mixels equation and everything we do without a radio or a mobile phone communication or exceed effective we see each other it's all describe but is very simple Maxwell equation that you see here it's so simple describe basically these two equations describe basically everything in our daily life
but there's more besides our classical world there's also a quantum mechanical world this is the world of atoms molecules very small particles and again we have a very simple looking equation it has a Greek symbol in it that makes it a little bit obscure but otherwise it's you know it's fairly short and please be impressed the dizzy creation the scripture equation scribes all of chemistry so
in some sense because our bodies are you a big chemical factories with all the atoms held together by quantum mechanical blue our existence thanks to quantum mechanics but maybe with this very question and losing another half of the audience the many people think well no the small particles that you do not my thing or formulas no that's I never have understood him I'm more of the
human scale I wanna feel things or or hear things or even touch things in that case you're the right person for me to talk to I will not show any more formulas in my presentation I would actually show you some quantum objects you can actually see you can actually hear them you can touch them so let's start it all starts actually up to a few minutes
ago before I came on states are called the mechanics was scribing very well and very accurate the world of atoms and molecules then at large scale and already started our our unit the biological cell it kind of stops if you don't use takes the cell as the fundamental unit to build up biology this is an enormous simplification because it completely ignores called the mechanics but it
is as best as we can do at this moment larger objects like our hair which is basically the smallest thing see of our ice or us you know the full classical but the small things can be described very accurately the people who put forward disappearing the quantum theory or actually or maybe they've they've made the no the most the greatest intellectual revolution or of mankind see
picture here with on the first row very prominent Albert Einstein do you recognize him in the middle on this right left for us there's handed Lawrence how Dutch hero and next to Lawrence we see madam Cutie and many of these men in this picture have received a Nobel Prize for their great work there's one person who got the Nobel Prize twice let's see actually the only
woman in the future madam Cutie so benefits through what they stated that women have to perform twice as good in order to be part of the gang she did it so this is a hundred years ago what's new well present day geniuses look like his this is a group of brilliant people the form our group at the Q. Delft but again they are at the verge
of a new quantum era we are no longer studying atoms and molecules as given by nature the culture so that we actually design and make our using very advanced fabrication techniques new objects much bigger but it still showed us this absurd clump mechanical behavior what is actually absurd about clinic in a foot why are we so excited about our quantum's let me give you two examples
of absurd quantum I can X. the first example of quantum superposition it's taken a particle like an election or something and bring it into a ring structure had a particle can you take the upper arm to get to the exit or take the lower arm to get to the exit now what actually happens upon McKenzie's if you elect them takes both arms at the same time
simultaneously really you know it's at sitting in the upper arm as well as in the lower arm at the very same time and we noticed because he followed the particle we see that the exit of the ring it actually collides with itself it bounces into itself and we observe these as interference it's such a soup position of being at two different locations at the same time
SB very thoroughly checked in all kinds of spirits welcome Sir the next example is the example of entanglement and we start very simple we take let's say a wreck particle and a white particle very classical colors then the next the peace that we bring them together and we may get into act a little bit sweeping a very close look at a city fuel each other and
I fear two of these interaction they become entangled they take over each other's properties so in terms of color they become white reddish that's okay curious thing happens if we take them being tango them and bring them apart and while taking them apart they remain entangled still the one that's on the left for you still has some properties of got a particle research that can be
a very large distance as far as the size of the universe so that's entanglement over very long distance particles keep having each other's properties so what can we do that can we actually measured at well the problem is that if we measure it we have a classical but sick color measurement apparatus the color measured up robs the classical thing so it can only give classical answers
so it says that's a wrecked or white so they say well particle on the left what is actually your color and I measure it its history since wrecked but maybe you noticed that the particle on the right at the same moment became white let's let's check it again I can I measure the left particle and the one on the road on the right immediately becomes light
it's because colour is a conserved quantity in the universe so if something completely turns red is something else where it used to be entangled with it's completely turning white and this action over a large distance I remember it can be the size of the universe Spartacus would be a part takes place instantaneous let me put it there a measurement of the caller on the left particle
immediately changes also the caller that far away as if I do something here and at the same time I change something dear without any signals traveling over to actually say well you just go there it's nothing in between much faster than the speed of light so this is a prediction from public theory and one guy Einstein set up that must be wrong any theory that predicts
spooky action on a distance do something here change something there that's that's a prediction tell us that the theory is wrong the safe possible tells a theory is wrong luckily we also have other heroes in physics this is a theoretical physicist called Richard Feynman and he said let's you know let's not be bothered with all these philosophical you know consequences of a theory calculate and see
what happens I'm here to Delft university of technology we we educate engineers the guys like me and I worked no approaches to the V. feel challenged and we say okay let's do it so what we do we take these two particles to bring them far apart and the big make it a bit more complicated to bring in a third particle the green one the green one
we bring to the left one we make these two interact I'm gonna left give them some interaction view the press carefully seated at the same moment Wendy's to interact and share some color also the particle on the right which was still entangled with the first one reading a lot of it the next is that I ask footballer hate left particles I do a color management and
differences turn white radish the same time the one on the right becomes green so look what I've done effectively start again opinion the green particle they entangle they also entail for the one in the right I click once more in the one on the right is now green I have teleported to green particle from the left universe to the right unit for over a long distance
so this teleportation is what we call let's say absurd or strange or you know very ought but we can do it and we we actually do it and actually we do this in the lab we've actually done it so many times that you actually made a student proof set up I can tell you if set up a student prove then it's you know it's a very
robust set up alright so what do we make we wanna make that some some stuff that we can actually use and do something with first of all a very simple example of a and libel it's of plain wire if you send a current through the why or if you decided by like it also luminescence a little bit of its like but this case the wires very
small it's only nine meters in diameter maybe my commute along that you let them know that you see we excite the system with some laser light we actually look what comes out of the wire if we do that yes you see little bit of a was it a bit of light coming out of it if the thing right that bright spot now what is special about
these bright spot fifty if you analyze it good detector it actually comes out as a stream of individual light particles one by one it's no longer a stream of light is really granular one comes out the next come out it's a trap and these are our photons that you use in these color experiments to teleport we give you another example different type of food you like
if you lowered the hearing person let me take a string and and and with all our strings guitar or violin whatever you believe attention on the string tone the music goes up the frequency the tone goes up so we've taken a very thin wire and nanotube only one on the meter in diameter we kissed have suspended over a trench reclaiming very tightly at two concert comdex
three exciting number two prison electric bills stocks to vibrate and we hear the tone now what is special about if your vibration resides very small so it's also very sensitive fifty at one electron one quantization of electrical charge to these not you it's a little bit extra tension intruding on it you it changes the tone a little bit let me hear some %HESITATION position could be
a bit more interesting but change in tone if you go from one level to the next level debt change it's in juice but one particular individual electron you here let me a %HESITATION live here again what you hear our individual call come potable let me give you the most recent example that's come straight from the lap of my colleague Leonardo di Carlo and actually need to
do something for these because we have did the car lap actually made a box the box already on the picture on the upper right if a few correctional connectors to and if I get my gloves on let's let me touch the books alright and a box it's big I can hold in my hands what we're doing now troop it's to make small electronic elements elements that
are so small that they can process information it completely differently instead of having bits or zero and once we want to make superpositions of bits as superposition of being zero and one at the very same time but you want to make them on an electronic circuit and what little the Carl has done is make three cubits I'm gonna you know I don't zoom in a little
bit in a few seconds if you already see the box if he cubits in it and these three cubits it can be put in a superposition or be entangled together in any arbitrary way between which well let me see if the camera can actually show you the cubits it's been more zoom this is my finger at cities the size of the system and you can I
hope you can see that there are three black spots on these courts plate these three black spots are about a centimeter away from each other and these are our cubits I keep its which are in a quantum superposition and we can a tangle different cubits together so the crew were now on a chip or centimeter size but he did this is between the different committees about
a centimeter and we can perform all this quantum of certain is on this ship and visible links can alright so you see it of course it only works if the details are fabricated very you know decisively and the details are not a meter scale so it's not just that every said to me to object starts to behave called mechanical the you really have to engineered very
precise down to nanometer scale that's a picture that you see right here okay let me zoom out a little bit what are we trying to do here well we actually want to make what the mechanical system I use the richness of quantum systems like the extra possibilities of being sued positions and they're having a very fast teleportation over long distances also think technology to make applications
that are much more efficient than we have today and particularly no because reading the fucking information business we wanna extend build quantum and the level of quantum from the atom to return system that is already the case that's working very well but what we want to bring it even up to a higher level of complexity the complete electronic circuit behaves quantum mechanical and it would we
need so much inefficiency you would not believe it and that would also make I'll get used a lot faster now only a few years ago people also in our field were saying that that's not gonna happen that inherently impossible is quantum mechanics to bring them up to a larger skills of size and complexity but if the progress of the last few years I can really say
here actually I'm saying it for the first time in public no did did clear that it will come yes we will be able to make quantum circuits and the quantum computer will only take maybe a decade later so alright let me conclude here we could take home estates I started with some some equations including one for for quantum mechanics but there's one message that up to
