The Insane Mechanism of a Quantum Computer?

Ғылым және технология

(To study Quantum Computing in depth, go to: brilliant.org/arvinash -- you can sign up for free! And the first 200 people will get 20% off their annual membership. The Brilliant course, "Quantum Computing" is one of the best offered online today! Enjoy!
Chapters:
0:00 - Quantum Computers
0:55 - Common computer components
2:51 - What is a Transistor?
3:20 - What is a qubit?
6:07 - Advantages of superpositions
6:40 - How does a quantum computer compute?
7:30 - Quantum algorithms
8:54 - What kinds of problems can Q computers solve?
10:32 - Why are quantum computers difficult to build?
11:50 - Is the universe a giant computer?
Summary:
(This is part 1 or at least a 2 part series on quantum computing. Each video will be successively more in-depth.) Classical and quantum computers share many general components - power supply, data storage, RAM memory, motherboard, but they differ in the way the central processing unit (CPU) works. A classical CPU is made from transistors, which is like an on/off switch. If it is on, then it’s like the number 1 or true. If it is off it’s like the number 0 or false. This is what binary means. A transitor represents a binary bit.
Quantum computers do not use binary bits, they use quantum bits or qubits. What is a Qubit? It is a bit in a superposition of 1 and 0. What does superposition mean? Quantum theory shows that quantum objects such as electrons, prior to measurement, are in multiple states at the same time. So something like the spin of an electron, which is a measurement of its intrinsic angular momentum, when measured is either up or down. When not measured, it is in both states of up and down. This is what superposition is.
If you visualize a qubit as a sphere, a classical bit can be 1 or 0 - the north pole or south pole. But a qubit can be in any place on the surface of this sphere depending on the superposition. A single qubit can be any mixture of 1 and 0, so the possible values are infinite! So whereas the classical binary bit can only take one of two values, the superposition allows a qubit to take on a potentially infinite number of values.
A qubit can be created by any quantum object like photons, electrons or even atoms. It doesn’t really matter. It just needs to be a quantum object in superposition. Qubits allow us to ask several questions at once during computation, “what is the result if the qubit is one? What is the result if the qubit is zero? What is the result if it is anything in between?”-- thus we can calculate the process where the bit is both zero and one and anything in between.
This downside is that the result of the computation will also be in superposition. This means that the quantum computers needs to maintain superposition throughout the process. The inputs AND outputs are both in superposition. The quantum computer operates WITHOUT any measurement of any kind. Because there are no measurements, the computer state evolves according to quantum mechanics.
The computer follows multiple computational paths at the same time, analogous to the way a photon could follow multiple paths through a double slit experiment. It only has a certain probability of ending up on certain locations.
However, at the end, there has to be a measurement to get a final result. And this final result from the computer is always classical. It is going to be a one or zero. How do we know whether we should get a one or zero? This is controlled by the quantum algorithm, which are clever programs created by programming scientists that use mathematical tricks to make sure that the probability of getting the correct is answer is as high as it can be.
How do quantum Algorithms work? They word by applying destructive interference on the wrong results, and constructive interference to the correct results. It does a kind of interference experiment to find the most likely answer.
So how is this so much more powerful than classical computers for solving problems? The quantum computer doesn’t do the usual stuff in a faster way. It doesn’t calculate all the possible results very quickly. It calculates all functions for all inputs at once. It calculates multiple functions at once for multiple possible inputs.
#quantumcomputer
Why is it hard to build quantum computers?
Qubits have to be isolated from the outside world. They cannot interact with any molecules or photons or other particles. This requires extreme cooling, because heat can modify or destroy the superposition by interacting with Qubits. So, this is why quantum computers are cooled to near absolute zero, that’s -273 degrees Celcius, to effectively eliminate all external thermal energy, so that the superposition is not modified or broken. In addition, Qubits can’t talk to the outside world, but they have to be able to talk to each other very fast. So these connections that the qubits must have with each other is not trivial.

Пікірлер: 593

  • @PranavKothare
    @PranavKothare2 жыл бұрын

    This is the first video that I've seen that doesn't just talk about the hype behind quantum computers or ELI5 qubits, but rather bridges the gap between the two domains (physics and computer science) in a meaningful way.

  • @daarom3472

    @daarom3472

    2 жыл бұрын

    Check out Scott Aaronson Lex fridman or Sean Carroll

  • @MrBendybruce
    @MrBendybruce2 жыл бұрын

    Clearest explanation of Quantum Computers I've seen. Great job Arvin.

  • @hqcart1

    @hqcart1

    2 жыл бұрын

    I've seen way better

  • @MrBendybruce

    @MrBendybruce

    2 жыл бұрын

    But that's only because you are way smarter than everyone else

  • @hqcart1

    @hqcart1

    2 жыл бұрын

    @@MrBendybruce Thank you!

  • @amanak65

    @amanak65

    2 жыл бұрын

    No doubt at all.

  • @EinsteinKnowedIt

    @EinsteinKnowedIt

    2 жыл бұрын

    So true 👍. With a little voodoo, everything is clearly understood. 😅

  • @dandwyer3919
    @dandwyer39192 жыл бұрын

    As an electrical engineer for 35 years this is the simplest clearest explanation of a quantum computer I've ever seen amazing job Arvin

  • @JR-ng9yo

    @JR-ng9yo

    2 жыл бұрын

    AGREED! I've been an EE for 45 years... studied some QM back at school... but this beats Matt, Sabine and many others. Clear, concise... and specifically addresses issues that are commonly misunderstood, and not explained by others. Thanks, Arvin!

  • @soulextracter

    @soulextracter

    Жыл бұрын

    @@JR-ng9yo And yet it still seems like he doesn't really explain it fully. He says that since the qubits are in a super position, the computer can check every path in a maze at once, but when you measure the result, the wave collapses and you get a classical answer. But how does it check several paths at once by just casually existing in constant spin? And how does it determine the correct path? I know he said that they use constructive interference to enhance the correct waves, and destructive to cancel out the incorrect ones. But how do you know which ones those are if you don't get an answer until it's all done anyway. I don't get it.

  • @JR-ng9yo

    @JR-ng9yo

    Жыл бұрын

    @@soulextracter "how does it check several paths at once"... This is done using "parallelism". Imagine having fifty 8X11 sheets of clear plastic, each with a random number of ink spots on it randomly distributed across it. You are asked to find which single ink spot out of all spots on all 50 sheets is closest to the top right corner of its sheet. You could number all sheets 1-50... use calipers to measure each spot on each sheet to the upper right corner... you could probably simplify by disregarding many dots and only measuring those that look closest... you could keep notes on sheet number and distance... and eventually derive the answer. *OR* you could stack all 50 sheets into a pile... and *look thru all sheets at once* and quickly determine which dot out of all dots on all 50 sheets is closest to its upper right corner! That, my friend, is *PARALLELISM* !

  • @sargismartirosyan9946

    @sargismartirosyan9946

    9 ай бұрын

    😮😮😮💀💀💀💀💀💀💀💀BRUH I'm also an electrician but I am also a programmer but I completely do not understand it

  • @yeet7135
    @yeet71352 жыл бұрын

    *"What makes a quantum computer fundamentally more powerful?"* Simple, it has the word 'quantum' in it.

  • @bobthedog3337

    @bobthedog3337

    2 жыл бұрын

    If you order one from Amazon, you only know if you have it when you open the box and look. You might have a dead cat. Or not.

  • @Lysirell

    @Lysirell

    2 жыл бұрын

    @@bobthedog3337 Your comment is gold lmao

  • @Lell19862010

    @Lell19862010

    2 жыл бұрын

    Does it have graphene inside?

  • @stuartstuart321

    @stuartstuart321

    2 жыл бұрын

    Yes makes no sense.

  • @JR-ng9yo
    @JR-ng9yo2 жыл бұрын

    *Arvin, your vids keep getting better And BETTER!!* This one answers questions I've had for years that no other vid I've watched addressed (and I've watched A LOT!). You seem to understand where people's misconceptions are. You've also scooped other publishers with the most current news! You have a knack of explaining things clearly and concisely, making your talks the easiest in this field to understand! You ROCK!! Keep it up!!

  • @mikepoulin3020
    @mikepoulin30202 жыл бұрын

    I asked my friend if I should build a quantum computer and he gave me infinite answers, so I slapped him until he gave me a yes or no answer....

  • @kai6179

    @kai6179

    2 жыл бұрын

    Love it. Seams like it's exactly how it works.

  • @alexejfrohlich5869

    @alexejfrohlich5869

    2 жыл бұрын

    i guess threatening to kill his cat didn't work either?

  • @dc174

    @dc174

    2 жыл бұрын

    @Mike Poulin 😂

  • @michaellastname4922

    @michaellastname4922

    2 жыл бұрын

    @@alexejfrohlich5869 only had a 50-50 chance....

  • @SaiSS961

    @SaiSS961

    Жыл бұрын

    😂🤣

  • @jonathancunningham4159
    @jonathancunningham41592 жыл бұрын

    You coveted this topic way more in depth than other sources. This is why I love this channel. No matter how much you think you understand something, you always learn something new. Thank you! Also, the animations were top notch!

  • @vm-bz1cd
    @vm-bz1cd2 жыл бұрын

    Fantastic ! 👏 one of the best and simplest explanations of quantum computing I have seen..

  • @vittoriolufrano9814
    @vittoriolufrano98142 жыл бұрын

    This was an Amazing explanation!

  • @sadderwhiskeymann
    @sadderwhiskeymann2 жыл бұрын

    great vid!! can't wait for the follow up!

  • @HassanGaba1
    @HassanGaba12 жыл бұрын

    Up until now I may have seen 2 dozen videos about quantum computers on KZread, and when I saw the notification for this video, I almost skipped it. But Im glad I didn't skip this video because this is the most comprehensive explainer video about quantum computers on KZread right now. Im kinda shocked you were able to condense all the information in less then a 15 min video

  • @ganeshnimbalkar2792
    @ganeshnimbalkar27922 жыл бұрын

    This is the first video I will recommend anyone, If they want to know what is quantum computer. Your explanations are clear and concise.

  • @arjunsahi123
    @arjunsahi1232 жыл бұрын

    What an explanation. I tried searching some videos but couldn't able to understand that clearly until I saw this. Thank you 😊

  • @velonaut303
    @velonaut3032 жыл бұрын

    This by far the best explanation I've found. Amazing job.

  • @efispass6630
    @efispass66302 жыл бұрын

    Awesome as always, can't wait for the next video my friend! If all the educators were like you!

  • @amanak65
    @amanak652 жыл бұрын

    You're one of the best out there Arvin. Love all your videos. Keep going and keep spreading them A1 quality info.

  • @manuelmartinez-gq4ij
    @manuelmartinez-gq4ij2 жыл бұрын

    I’ve been away for a bit, but glad to be back. I’ll get caught up on your education. Your a gift and I appreciate your efforts.

  • @KamilsView
    @KamilsView2 жыл бұрын

    Awesome video/presentation. Can't wait for the next part!

  • @krisdouglas6536
    @krisdouglas65362 жыл бұрын

    Amazing ! Can’t wait for the next part.

  • @leifefrancisco7316
    @leifefrancisco73162 жыл бұрын

    Great job man! You answered all my questions.

  • @joemato
    @joemato2 жыл бұрын

    Been searching long time for KZread videos that could explain to me in simple way the difference between a quantum computer against a classical one. Arvin explained it very well. I think the reason why most failed it's because they want to scale up the the understanding of laymen like me to their level, which may never happen, instead of the other way around.

  • @ganindunanayakkara8970
    @ganindunanayakkara89702 жыл бұрын

    Thank you, the best explanation I've seen so far!

  • @maheshBasavaraju
    @maheshBasavaraju2 жыл бұрын

    I never understood before how quantum computing worked. I finally understood today.. thank you Arvin !!!

  • @emilyquisourit
    @emilyquisourit2 жыл бұрын

    Another great video. Thank you Arvin! 😊

  • @kjthompson6513
    @kjthompson65132 жыл бұрын

    Excellent! A simple explanation of quantum computing equals understanding. Nice!

  • @craigo8598
    @craigo85982 жыл бұрын

    Thanks Arvin, great video and very clear, and the hat is so gangsta!

  • @abdulrazak9945
    @abdulrazak99452 жыл бұрын

    Awesome explanation!! Thanks much Arvin.

  • @debasisdas7682
    @debasisdas76822 жыл бұрын

    Thank you for offering crystal clear views for a starter

  • @seanyiu
    @seanyiu2 жыл бұрын

    Hi Arvin, Awesome Video. Better than anything from Google or IBM in trying to explain the gist of a Quantum Computer and that means better than anything out there, period. You covered all the key principles that matter to a holistic understanding. Really props to you !

  • @ArvinAsh

    @ArvinAsh

    2 жыл бұрын

    Much appreciate. Glad it was helpful!

  • @MeowtronStar
    @MeowtronStar2 жыл бұрын

    Finally a verbal explanation and example of quantum computing that actually makes sense instead of sounding like buzzwords.

  • @LQhristian
    @LQhristian2 жыл бұрын

    Great video, very concise explanation!

  • @johanneskrv
    @johanneskrv2 жыл бұрын

    Very good video. One of the best explanations I've seen.

  • @adamrafal6587
    @adamrafal65872 жыл бұрын

    Damn! That was REALLY good! Thank you, Arvin!

  • @jasemalhammadi4228
    @jasemalhammadi42282 жыл бұрын

    Many thanks Arvin Can’t wait to see the next video. Perhaps some applications of quantum computers in the next video may make this topic more clear. What about quantum networks? Where can we study or specialize in quantum computers? Apparently it’s not covered thoroughly in university’s program of computer science.

  • @frankhoffman3566
    @frankhoffman35662 жыл бұрын

    Very good explanation with very understandable animation. "A quantum computer takes all possible paths at once". Well done

  • @peterpan629
    @peterpan6292 жыл бұрын

    I really enjoy watching your episodes. Excellent explanation 👍

  • @anilkg26
    @anilkg262 жыл бұрын

    Perfect explanation. Thank you.

  • @GururajBN
    @GururajBN2 жыл бұрын

    Output is in superposition. Picking the right option is the trick. This is still at equation stage. Never say impossible! Excellent presentation of a very esoteric topic.👌

  • @kylorenkardashian79
    @kylorenkardashian792 жыл бұрын

    Arv 🔥 you're always blowing my mind

  • @srijantiwari8152
    @srijantiwari81522 жыл бұрын

    Very interactive . Learned a lot from this

  • @servalkitty5862

    @servalkitty5862

    2 жыл бұрын

    In what way was it interactive?

  • @dray7579
    @dray75792 жыл бұрын

    Wow arvin im speechless especially that last bit about the universe.

  • @tasonovin

    @tasonovin

    2 жыл бұрын

    Q

  • @maxmuster7003
    @maxmuster70032 жыл бұрын

    The first video that focus the importent stuff. Thx. Now i start to understand how it works.

  • @mosenwani
    @mosenwani2 жыл бұрын

    Great explanation comes from great understanding.

  • @jamalnamdari4934
    @jamalnamdari49342 жыл бұрын

    Thank you Arvin amazing explanation

  • @noahway13
    @noahway132 жыл бұрын

    Is my brain a quantum computer? I don't search every phone number I know for the correct owner, I don't search every single face I know to recognize Arvin Ash.

  • @Bobbias
    @Bobbias2 жыл бұрын

    I seriously hope you're working towards explaining shor's algorithm. I've never actually seen a proper explanation of the math behind it, but if anyone can explain that in a way to follow way, it'd be you.

  • @cesarjom
    @cesarjom11 ай бұрын

    This video was a special one, very good way to explain quantum computing using basic principles of QM.

  • @mashfour
    @mashfour2 жыл бұрын

    That was Brilliant..thanks. The Maze animation explained superposition and measured result best. I'm presuming the hat is to keep your brain in! 👍

  • @innertubez
    @innertubez2 жыл бұрын

    As usual Arvin Ash provides the best explanations - clear and understandable. I’m just curious about the limits of quantum computation with regard to Grover’s Algorithm. Square root is an amazing improvement for searching data points, but seems like little help with a googol data points or, say, a Graham’s Number of data points.

  • @bharathreddygudibandi492
    @bharathreddygudibandi49211 ай бұрын

    Very clear explanation!!!!

  • @iroh1796
    @iroh1796 Жыл бұрын

    Thank you Arvin. I love your videos!

  • @hasanshirazi9535
    @hasanshirazi95352 жыл бұрын

    You are the man. Great explanation.

  • @Jonathan-rm6kt
    @Jonathan-rm6kt2 жыл бұрын

    That was an amazing explaination

  • @merendaakina
    @merendaakina2 жыл бұрын

    Great content as always

  • @tarnished7117
    @tarnished71172 жыл бұрын

    I cannot wait for the cpu video cause I have been wondering about the fundamental processes of a computer for a while now and I can't seem to find much compiled online.

  • @GEMINDIGO
    @GEMINDIGO Жыл бұрын

    Fu%king out of it as usual !! Thanks Arvin!

  • @shourovesharma8794
    @shourovesharma87942 жыл бұрын

    Wow,,. Your explanation is Great 😮

  • @GouthamR013
    @GouthamR0132 жыл бұрын

    Ooh the ending was just epic😍😍

  • @jlpsinde
    @jlpsinde2 жыл бұрын

    Great as always

  • @luckybarrel7829
    @luckybarrel78292 жыл бұрын

    I loved this explanation. Also understood how the parts of the computer interact with each other better here. Wasn't expecting it to end with the universe is a simulation theory, but it kinda does make sense to end with here.

  • @Dragrath1

    @Dragrath1

    2 жыл бұрын

    Note that there is a significant difference between a "computational universe" and "simulation theory" whiich he left ambiguous as it can apply to both. A simulation theory requires a physical computer outside the simulated universe but a computational universe is one where the computation is the fundamental bit not built on top of anything but past computations acting on some network array of past logic operations. It is a bit conceptually strange to think of as historically we have always thought of a computer as a physical object performing an operation but in a computational universe the computations are the fundamental building blocks from which familiar properties like space, energy momentum etc. emerge. So rather than a physical computer simulating a system you are more or less projecting a piece of the underlying computational reality which acts as the fundamental building blocks of the universe. That is to say in the computational universe paradigm if the underlying computational simulation is sufficiently accurate i.e. has the right algorithm running on the right network then there is fundamentally no difference between the simulation and the and the simulating universe aside for the snapshot in time. i.e. the simulation is really an observation of the past in such a precise scenario. The catch of course is that the rate of times passage would be identical between the simulating universe and all the simulations so you could only know if you got the right network and algorithm for sure after running the simulation for 13.8 billion years. Other algorithms and starting networks wouldn't be wrong per say they would just show you a different snapshot of the computational universe in essence what is conventionally the "multiverse". Additionally in this paradigm the question of whether math is discovered or invented is rendered trivial as an observation is a frame or reference in space and time and a measurement is a type of acceleration in the space of all possible outcomes of the wavefunction with the observation being a single projection of that higher dimensional object in a lower number of dimensions. It is a very trippy paradigm that is really hard to grasp in fact it is probably fundamentally impossible for the whole system to be represented by our puny brains.

  • @bobd6711
    @bobd67112 жыл бұрын

    Brilliantly dumbed-down for consumption. I love this channel!

  • @magamindplanet8930
    @magamindplanet89302 жыл бұрын

    great video 🔥🔥

  • @PaintballVideosNet
    @PaintballVideosNet2 жыл бұрын

    Very well explained.

  • @w.a.ffilmmaker1208
    @w.a.ffilmmaker12082 жыл бұрын

    I want more video related to this topic I always want to how computers works in detail Can you make a full series about Classical and Quantum computer

  • @alexejfrohlich5869

    @alexejfrohlich5869

    2 жыл бұрын

    regarding classical computer, check out the "crash course computer science". it explains everything about how classical computer works and is awesomely fun to watch :) kzread.info/dash/bejne/pqR9xdayoauYabQ.html

  • @MsCodename84
    @MsCodename842 жыл бұрын

    this topic reminds forgotten analog computers, its interesting that some deprecated technologies not useless in some new researches

  • @adityakumar4869
    @adityakumar48692 жыл бұрын

    Thank you for the video

  • @Hansulf
    @Hansulf2 жыл бұрын

    Nice! Now the hard part: explaining how the hell you go from qbits to the algorithm

  • @CommodoreFloopjack78
    @CommodoreFloopjack782 жыл бұрын

    Interesting stuff. I'm still waiting for a quantum Etch-A-Sketch. Fun for the whole family!

  • @jeffreyspinner9213

    @jeffreyspinner9213

    2 жыл бұрын

    Fun for every family at once (!)

  • @CommodoreFloopjack78

    @CommodoreFloopjack78

    2 жыл бұрын

    @@jeffreyspinner9213 😁😆👍

  • @kylorenkardashian79
    @kylorenkardashian792 жыл бұрын

    3:20 the overall graphics were fantastic & intuitive

  • @drewz9807
    @drewz98072 жыл бұрын

    Great video as always. A couple of questions: 1) I can understand how a quantum computer can process data to achieve a desired result, but how does one encode the data in a qbit? Is this possible to do without interacting with a quantum state? 2) the algorithm used to increase success chance of measuring the desired outcome: does this mean that the computers user must know the desired outcome prior to doing any computation?

  • @mreatboom1314

    @mreatboom1314

    2 жыл бұрын

    1) Actually you can't. The phone book is thus not a really good example because you wouldn't be able to encode the data in your computer. The maze is a good one because the information is easy to encode 2) Of course no or it wouldn't be interesting. For some algorithm the solution is hard to find but easy to check (prime number for instance) so you could just check. For others it's not and here you would just repeat a lot the algorithm until you are confident enough you have the right anwser

  • @DJSouthFlorida
    @DJSouthFlorida2 жыл бұрын

    Great job 👏

  • @calvingrondahl1011
    @calvingrondahl10112 жыл бұрын

    Fission and fusion too. Maintaining a constant fusion reaction for constant power source. Small steps of progress. Bits and Q-bits...

  • @bumandy
    @bumandy2 жыл бұрын

    Yes, I agree this is the best video on quantum computers but still didn't explain how to do the computations. I hope it's in next teaser video

  • @keep_walking_on_grass
    @keep_walking_on_grass Жыл бұрын

    this is mindblowing

  • @mr.expressional6822
    @mr.expressional68222 жыл бұрын

    Well now. That was quite helpful.

  • @vedantsridhar8378
    @vedantsridhar83782 жыл бұрын

    Hey Arvin Ash such an excellent interesting video that was so well explained! Just a question, what was the music you played at the end or at 13:18 and who's the artist? That music really gives me chills. Or can you send me a link of that music? You've used this spooky music in many of your other videos too.

  • @martir.7653
    @martir.76532 жыл бұрын

    I don't get the explanation of qubits. In classical *analog* computers, a signal can also have values anywhere between 0 and 1, represented by different voltage levels. Surely there must be something more to how qubits work?

  • @vibaj16

    @vibaj16

    2 жыл бұрын

    1, A classical computer doesn't actually use that in between value. It just counts any voltage below a threshold as 0, and anything above it is a 1; and 2, a quantum computer uses superposition to try every possibility at the same time, while a classical computer has to try one operation at a time

  • @pinocleen

    @pinocleen

    2 жыл бұрын

    The answers missed the "analog" part of the question so, the difference is that qubits are superimposed sets and friendly to algorithm manipulation, which is what gives it its power.

  • @drdca8263

    @drdca8263

    2 жыл бұрын

    Indeed. The video did not explain it. Here is an *actual* explanation. First, you need to understand the concept of a vector space. A vector space is a set of things where you can scale them by a number, and add or subtract them. The things in a vector space are called vectors. There is a more precise way to define vector space, but the precise details are just the things one would expect from making the description I just gave precise. An example of a vector space is like, the space of triples of 3 numbers, like (x,y,z) , where you can like, say 2.5 * (1,4,2) = (2.5,10,5) , and (2,1,11) + (1,1,1) = (3,2,12) . Another example of a vector space is just "the real numbers". In quantum mechanics, (or at least one of a couple of mathematically equivalent ways of describing it), the state of a system is always a vector in a certain vector space. This vector space is of a certain kind, called a "Hilbert space". A Hilbert space is a vector space where you have a concept of the length of a vector, and also a concept of vectors being perpendicular, and the Pythagorean theorem works, and also if you have an infinite sum of vectors which should converge, then there actually is a vector for it to converge to (this last property is something you don't really need to worry about for this explanation). In quantum mechanics, the vector which describes the current state of a system always has length 1. An example of this is what he was *trying* to get at when he said that alpha^2 + beta^1 = 1 (though really he should have said that |alpha|^2 + |beta|^2 = 1 in case alpha or beta had an imaginary component) Now, you need to know what a linear operator (aka linear function aka linear map) is. Now, a linear combination of a collection of vectors is just a sum of the vectors each multiplied by some number. For example, 2 * (2,11,2) + 4 * (1,2,3) is an example of a linear combination of (2,11,2) and (1,2,3) . Another example would be 2 * (2,11,2) + 0 * (1,2,3) . The linear combinations don't have to just be between 2 vectors either, they can have as many as you want. A linear combination of vectors from some vector space, will always be a vector from the same vector space. [side note : the "dimension" of a vector space is the smallest size a set of vectors from that space can be, such that every vector in that vector space can be expressed as a linear combination of vectors from that set.] A linear operator is a function which takes input an element of some vector space, and has outputs elements of some vector space (often but not always the space it takes input from, and the space it gives output in, are the same space) such that, it sends linear combinations to corresponding linear combinations, in the sense that, well, I'll give an example, that will be easier. If A is a linear operator, then A( 5 * (1,4,2,7) + 2.1 * (1,1,2,2) + 3000 * (4,3,2,1)) = 5 * A((1,4,2,7)) + 2.1 * A((1,1,2,2)) + 3000 * A((4,3,2,1)) . And, note: A doesn't "know" that its input was in the form of a linear combination of the set of vectors I expressed there, all the info A gets is the vector (12007.1, 9022.1, 6014.2,3039.2) (which is what that linear combination I wrote evaluates down to. I kind regretting picking not-nice numbers in that example) Now, in quantum mechanics, basically everything is done using linear operators. In particular, time evolution, the "given what things are like now, what will they be like in 2 seconds" (or, any given amount of time) is a linear operator. So, if the computer state is a linear combination of some state and another state, then because time evolution is linear, after the computer does stuff, the computer state ends up being in a corresponding linear combination of what time evolution would do to the corresponding components, and the relative coefficients between them. Now, suppose that we have some vectors in the Hilbert space for our quantum mechanical system, and let's say these vectors are named, idk, banana, Zamboni, purple, and Sasquatch, and they each have a length of 1. Suppose that purple and banana are perpendicular, so then (by the Pythagorean theorem ) the lengths of ((1/sqrt(2)) * purple + (1/sqrt(2)) * banana) and ((1/sqrt(2)) * purple - (1/sqrt(2)) * banana) each have a length of 1 (because (1/(sqrt(2))^2 = (1/2) , and (-1/(sqrt(2))^2 = (1/2) , so in both cases we get (1/2) + (1/2) = 1 ) Ah, now there's something I should have probably mentioned earlier (it gets a bit confusing trying to explain just enough linear algebra to explain quantum mechanics while simultaneously explaining the quantum mechanics) : measurement! When there is a discrete set of possible measurement outcomes, we can associate with each one, a component of the state. For each possible outcome, there is a linear operator (a projection operator, as it happens) which sends any state to a component of that state which corresponds to that measurement outcome, and if you add up the components that these different operators give of the original state, they add up to the original state, and furthermore, each of these components are perpendicular to each of the other components. The square of the length of each of these components corresponds to the probability of measuring that outcome. That these add up to 1 represents the fact that "definitely there is something that happens", and also that this is by adding up squares of lengths of perpendicular things, is because of the Pythagorean theorem again. So, if there is a measurement we are doing which has possible outcomes "purple" and "banana", then, well, I named these measurement outcomes after the vectors I used before, so I hope it isn't too much of a surprise that I want the "banana" component of ((1/sqrt(2)) * purple + (1/sqrt(2)) * banana) to be (1/sqrt(2)) * banana , and the "banana" component of ((1/sqrt(2)) * purple - (1/sqrt(2)) * banana) to be (-1/sqrt(2)) * banana . Note the minus sign! But, in both cases, if we take the square of the length of the "the observed outcome is banana" component, in both cases, we get (1/2) (if instead of (-1/sqrt(2)) we instead had like, (sqrt(-1)/sqrt(2)) , well, technically we would multiply it by its complex conjugate, which is (-sqrt(-1)/sqrt(2)), and so the product would still end up being (1/2), but you can also just think of it as "we take the absolute value before we square it." But also, I'm getting into unnecessary details, you don't have to worry about this part.). (similarly a (1/2) chance of "purple" in both cases, but I showed "banana" to demonstrate what happens with the minus sign). Ok, now, suppose that the time evolution operator U, which sends a state to what the state would be after (say) 3 seconds, suppose it sends Sasquatch to ((1/sqrt(2)) * purple + (1/sqrt(2)) * banana) , and suppose it sends Zamboni to ((1/sqrt(2)) * purple - (1/sqrt(2)) * banana) . Because U is linear, it will send (1/(sqrt(2))) * Sasquatch + (1/(sqrt(2))) * Zamboni to (1/(sqrt(2))) * ((1/sqrt(2)) * purple + (1/sqrt(2)) * banana) + (1/(sqrt(2))) * ((1/sqrt(2)) * purple - (1/sqrt(2)) * banana) which simplifies down to (1/2) * purple + (1/2) * banana + (1/2) * purple - (1/2) * banana = purple . While, on the other hand, it will send (1/(sqrt(2))) * Sasquatch - (1/(sqrt(2))) * Zamboni (note the minus sign!) to (1/(sqrt(2))) * ((1/sqrt(2)) * purple + (1/sqrt(2)) * banana) - (1/(sqrt(2))) * ((1/sqrt(2)) * purple - (1/sqrt(2)) * banana) which simplifies down to (1/2) * purple + (1/2) * banana - (1/2) * purple + (1/2) * banana = banana . This is the sort of thing that he is talking about when he talks about the positive and negative interference. Sasquatch and Zamboni would each individually produce a superposition of purple and banana (two different superpositions, but if one measures whether banana or purple, the probabilities would be the same, though if one measured a different question the two could be distinguishable), but different linear combinations of Sasquatch and Zamboni result in either the purple components having negative interference and canceling out while the banana components have positive interference and become more likely, or visa versa, depending on which linear combination of Sasquatch and Zamboni is used. Ok, it is midnight, I probably shouldn't have taken the time to write all this on a youtube comment? But, if you have any further questions, let me know.

  • @vibaj16

    @vibaj16

    2 жыл бұрын

    @@drdca8263 you could've linked to a wikipedia article. A youtube comment can't hope to ever be very well formatted

  • @pinocleen

    @pinocleen

    2 жыл бұрын

    @@drdca8263 Mr. Zamboni, do you take credit card or paypal? great stuff +1

  • @yahoo07100
    @yahoo071002 жыл бұрын

    Best one I have seen

  • @josejoaquin1305
    @josejoaquin13052 жыл бұрын

    you blow my mind Arvin

  • @Nawwar1980
    @Nawwar19802 жыл бұрын

    This channel is the best on youtube.

  • @ISK_VAGR
    @ISK_VAGR2 жыл бұрын

    Arvin… still impress me with your clear explanations. How can a quantum computer determine what is the culprit (“pathogenic protein) of a disease when we evaluate 12K different proteins using proteomics for example? I ask this because I imagine that things get complicated when there are more than one answer. For example different proteins involved.

  • @ArvinAsh

    @ArvinAsh

    2 жыл бұрын

    It would find the most likely answers, provided you have some idea of what the answer should look like.

  • @esra_erimez
    @esra_erimez2 жыл бұрын

    Both classical and quantum computers also need RGB to work

  • @andyc9902

    @andyc9902

    2 жыл бұрын

    Lol typical female 😉

  • @bryanpascual3543

    @bryanpascual3543

    2 жыл бұрын

    quantum RGB: any light in between Red, Green, and Blue

  • @andyc9902

    @andyc9902

    2 жыл бұрын

    @dafuqawew kek

  • @B2PTWO-uq7ik

    @B2PTWO-uq7ik

    Ай бұрын

    😂 RGB? I think one more color is missing

  • @usama57926
    @usama579262 жыл бұрын

    Make two separate videos on entropy in thermodynamics and in information theory.....

  • @musyyabalam2726
    @musyyabalam27262 жыл бұрын

    quite excited for new video about LOGIC GATES!!!!

  • @ramizr
    @ramizr2 жыл бұрын

    Idk if you'd seen .....my request on Twitter to make a video on Quantum Computer or not . But , Thank-you so much for making video on Quantum Computer!

  • @5ty717
    @5ty717 Жыл бұрын

    Inspirational bro

  • @Cdictator
    @Cdictator2 жыл бұрын

    My favorite physics channel on KZread

  • @dilipdas5777
    @dilipdas57772 жыл бұрын

    Happy teacher's day from India. You are a great teacher

  • @toastoots2474
    @toastoots24742 жыл бұрын

    1:28 I can see the textures on the pc case glitching out lmao nice modeling

  • @cybermindable
    @cybermindable2 жыл бұрын

    In classical computers there are electronic circuits like adders, multipliers etc. that perform the actual computation -- produce outputs from inputs according to some rules. What are the substitutes for the circuits in quantum computer that, say, produce the sum of two numbers?

  • @mdderrek9280
    @mdderrek92802 жыл бұрын

    Thanks Arvin, nice to see the hat again.. I really hoped to know the practical applications of these computers.. It is still ambiguous.. I mean if I have one, what are the applications, the everyday ones.. Can I do my everyday stuff on it? What difference will i notice? what could and couldn't I do with it? In other words, *tell us a real life practical example of something we couldn't do before Quantum Computers, yet those computers allowed us to do it..*

  • @vibaj16

    @vibaj16

    2 жыл бұрын

    Here's a quite unfortunate practical thing you could do with it: a quantum computer could easily break a modern encryption algorithm in a few minutes, while a classical computer would take years, so any money saved on classical computers won't be safe. Hopefully quantum computers can somehow give us new encryption algorithms that can make up for this. Another thing: quantum computers could calculate neural networks much faster, so AI could have far more potential. A truly everyday practical example: I'm pretty sure a quantum computer would be much faster at computing many of the calculations required for 3D graphics and physics, which could give video games huge potential for way more advanced graphics and interactions without the performance suffering

  • @ArvinAsh

    @ArvinAsh

    2 жыл бұрын

    I think you'll find the next video on QC quite helpful with your questions.

  • @flopyrelly4281

    @flopyrelly4281

    2 жыл бұрын

    @@vibaj16 this is correct

  • @flopyrelly4281

    @flopyrelly4281

    2 жыл бұрын

    @@ArvinAsh can't wait for it! Like always, another amazing video! Thanks Arvin, you make difficult topics easy to comprehend.

  • @mdderrek9280

    @mdderrek9280

    2 жыл бұрын

    @@ArvinAsh Thank you, really!

  • @init_yeah
    @init_yeah2 жыл бұрын

    Probably thr best video that explains quantum computers without assuming you are stupid. Will the next part explain the logic behind quantum computers cpu?

  • @ArvinAsh

    @ArvinAsh

    2 жыл бұрын

    Yes, It will be all about the logic.

  • @init_yeah

    @init_yeah

    2 жыл бұрын

    @@ArvinAsh thanks 😊

  • @mimArmand
    @mimArmand2 жыл бұрын

    Thank you, Arvin, but how the number of iterations is reduced by the square root of the classical one? Something is missing here!

  • @ArvinAsh

    @ArvinAsh

    2 жыл бұрын

    Only using the Grover algorithm. There are other algorithms that work differently.

  • @emmepombar3328

    @emmepombar3328

    2 жыл бұрын

    @@ArvinAsh You could have provided at elast one example. The fundamental element of a quantum computer is not the qubit, but how an algorithm is applied. And this part, the only part that gives a quantum computer a meaning you totally left out.

  • @swamiaman7708
    @swamiaman77082 жыл бұрын

    Amazing.... in such a small video you gave many answers. I wonder if the human brain has something of quantum computers.

  • @drdca8263

    @drdca8263

    2 жыл бұрын

    "If you don't talk to your kids about quantum computing, *someone else will*" [cut to image of magazine which says "quantum computing and consciousness are both weird, and therefore equivalent."]

  • @lidarman2
    @lidarman22 жыл бұрын

    One analogy that I can think of is a quantum computer is sorta like using a large magnet to find the needle in the haystack--The magnet uses it's properties to search the whole stack at once.

  • @ArvinAsh

    @ArvinAsh

    2 жыл бұрын

    That's an interest analogy. Thanks.

  • @rainbowsally2001
    @rainbowsally20012 жыл бұрын

    Hi Arvin. Got anything on the aharonov bohm effect? This is REALLY hard to visualize, what with potentials that aren't fields and stuff. It's an interesting effect that can change the interference pattern in a double slit experiment by changing the phase of the particle(s) despite there being zero B or E fields. This one is probably REALLY tricky because nobody seems to be able to demonstrate it other than by way of the rather ugly math. No biggie it it's too crazy to even try, but you did a great job on entanglement and I thought you might be the one to bring this effect out in the open too. ..

  • @Company-59
    @Company-592 жыл бұрын

    Thank you is not enough to express my gratitude. Alas, thank you is what i can come up with 😇

  • @DezequielX
    @DezequielX2 жыл бұрын

    Great stuff

  • @code4chaosmobile
    @code4chaosmobile2 жыл бұрын

    great vid!

  • @Shreymani2
    @Shreymani22 жыл бұрын

    The last analogy tho.. 🔥🔥🔥

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