A beginner's guide to quantum computing | Shohini Ghose 

if the hackers break the laws of quantum physics in order to break the human laws, do they go to jail or go get a nobel prize, or both ?

To sum up: “It’s very complicated.” “It’s so complicated that we can’t actually explain it other than stating that it’s non binary” “It’s so complicated that it can change the way the world works” “If you don’t get it, you’re beginning to understand it”

"the future is fundamentally uncertain but certainly exciting "...WOW!

I really like her final thought about not seeing quantum physics just as a tool to build quantum computers, but quantum computers as a tool to better understand quantum physics and the nature of the Universe.

So basically the quantum computer waits until the user plays and just always picks the outcome where the computer wins? Yeah, sound like Vegas.

I must have missed the bit where she explained how quantum computing works :-(

User: Hey computer what's 2+2? Quantum Comp: wouldn't you like to know..

The coin-flipping thing told me absolutely nothing about how quantum computers work

A physicist friend of mine loves this quote...”if you say that you completely understand quantum physics, then it is obvious that you know nothing of quantum physics.” So, kudos to you for helping the masses at least understand a tiny part of it! I find the entire matter the most fascinating endeavor in science.

Quantum computing NOT explained in 10 minutes

Wow. Even after 2 years of this talk being on net, I was amazed to think what future has in store for us. Very good Ms Ghose

Hi , future people. I knew you will come back to this classic computer to check your innovation's past. Just don't forget that we have gems called memes, preserve them, they are very precious.

Thanks for making that quick. I can now relax in a quantum of solace.

The computer won by cheating, because after it's first "flip or no flip" it did neither, it claimed it was in some "partial heads partial tails state". That's cheating.

I'm looking forward learning more (and understanding in my own way, by being confused) about this topic that lures and fascinates me and I consider Shohini Ghose managed to speak about a large scale of it in a beautiful way.

Actually I did kind of get this. We know that modern computers work with bits representing 1s and 0s and combinations of them to represent data. Bits can only ever be a 1 or a 0, but never both at the same time, the same as when you flip a coin and see the result, you can't have heads and tails at the same time. With a quantum computer however, bits can be both 1 and 0 at the same time. If you understand Schrodinger's cat, it's basically the same principle, it's only when you look into the box will you see whether the cat is dead or not, but you can never know the answer until that, so you have to accept both possibilities at the same time. That's why quantum encryption is unhackable, because even if you manage to "see" the data in it's quantum form, it's kinda like you're trying to figure out whether the cat is dead or not. If you ever delve deep enough into chemistry and physics, you might have heard that, rather than orbit the nucleus like a planet in a predictable path, it's kind of impossible know where exactly an electron is, it's at every point around the nucleus at the same time whilst also not being there as well. *mind explodes*. The fact that we struggle with these mind boggling concepts and pinpoint things is precisely why the quantum computer is useful. It's bits behave the same way. That's why it's useful for chemistry, because it imitate the behaviour of atoms in the same black magic way, we can model reactions without having to worry about the infinite crazy possibilities the direction of a particle might fly off to, and then translate the important information to us in a digestible format. At least that's what I'm getting.

Amitab bachan in the movie sholay had the quantum physics coin.

err I think she did a very bad job explaining Quantum computing by using games that has rules defined by binary winning/losing. And have quantum computer changing the rule to win? There are many ways to explain how quantum computing works - this is not one of them.

It must be a superposition of an explanation and a non-explanation

Person: "Excuse me, sir" Quantum computer: "It's MA'AM!"

"If you are confused by quantum, don't worry. You are getting it." Wow, that's a really sly way of pretending you're explaining something when you aren't at all.

Finally, I can slap someone through the internet

Great job Dr. Ghose. I love simplifying complex stuff and your explanation of such a complex topic was brilliant. Especially, the idea that it is a fluid mix and that the computer will un-mix after the user. GREAT JOB!

I've watched a lot of introductory videos about quantum computing, and even took courses for it, but no one explained the basics the way she did. It was so amazing to watch this TED talk!

this doesn't explain much about how it works at all.

Quantum computer in a nutshell: - Guess the number I made - 5? - No, it's 3. I win. - But...you could change it after I said - I wouldn't need to because the number I made was in a superposition and it revealed right after your number...sorry buddy, that's quantum mechanics I hope that explanation is enough.

WHAT WOULD HAPPEN IF TWO QUANTUM COMPUTER PLAYED THIS GAME WITH EACH OTHER, WHO WILL WIN ASSUMING BOTH HAVING SAME PROCESSING SPEED🤔

Is it heads or tails? Quantum Computer: Both

They didn't even talk about what this means for specialized mathematics and storage capacities. A classical bit(Binary Digit, [0, 1]) is an characterized by a O(n^2), while a qubit(Quantum Bit) is characterized by a O(2^n). This makes seemingly enormous problems somewhat more manageable. For example: Say a classical computer the size of earth would have about the same computing power as quantum computer the size of an elephant(theoretically). They fundamentally work differently, so don't expect quantum computers to make your phone or laptop any faster, but for the scientific community that need solutions to extremely large data-set problems, or fundamentally complex can now be rapidly calculated.

The real question is can it run minecraft with shaders?

Beautiful presentation! Very exciting possibilities to explore!

Super amazing!! I absolutely loved the way she conveyed it 💯❤️

There is no spoon. You meant a fork. No, it's a spork.

ME: Hey, Quantum computer: This statement is false. Think about that. QC: Your statement is tralse. ME: Damn you, wretched quantum machine!

Being an physics student, you inspired me to research on quantum computers

One of the best explanation I have found so far.

Thank you for destroying what little understanding I thought I had before seeing this video

TLDR It just works

This is so interesting and she explains it so simple.

as a computer science graduate who's weak in physics and being forced to learn about quantum computing, having to watch this in hopes of getting any understanding at all was .... well like playing coin flipping with a quantum computer... hardly any chance for me to get something out of it. And the comment section is more satisfying than the video.

explaining why it's okay to be confused by quantum computing in 10 minutes

My knowledge bank is increasing daily. Thanks so much Ted x for creating a platform like this.

That make no sense. You are flipping a coin but the computer is flipping a sphere. You are not playing the same game.

Damn i loved the way she taught us the concept of quantum computing very knowledgeable and fascinating. Thanks ma'am

So, the whole "teleportation of information" thing is a misnomer which is highly confusing for people not familiar with quantum mechanics. When 2 elementary particles, A and B, are interacted together, you can measure their sum to be 0 charge or 0 spin, which means one has +1 charge and one has -1 charge, or +1 spin and -1 spin. You don't know which of the two has what, but they never un-entangle themselves. You can separate the particles by as much distance as you'd like, and separately observe them to be +1 and -1, but A cannot be locally affected by B faster than the speed of light. If you only observe A, then B will collapse into the opposite state for as long as you observe A. Once you stop observing A, both A and B become randomized again until you observe them, at which time they can again be +1 or -1, randomly. This is called a non-local effect, because A and B effect each other regardless of separation in spacetime. But anything that A does (say, an electron making a magnetic field) that can travel to B's location and then affect B does not happen faster than the speed of light. In essence, that means this is useless for teleportation of information. Hope I wasn't too confusing...

Discovering a new possibility on something we weren't aware is always thrilling.

You know what they say... "You don't know where it is but you know how fast it's moving and you don't know how fast it's moving because you know where it is. It's just quantum physics"

Simple but effective presentation, thanks to Shohini Ghose. :D

Feynman : "If you think you understand quantum mechanics then you don't understand quantum mechanics"... trying to make sense of quantum physics in 10 minutes doesn't make any sense. Nothing in the quantum world makes sense anyway

Furthermore I do not think you can effect changes through entanglement. You can observe the entangled particle's statistics and correlate them. But no instant changes can be made after that.

Clearest explanation so far on QC

2:31 is a great analogy

What quantum computing actually is. Binary: 0 or 1. Never one and the other or both Trinary: 0,1,2. Never one or the other or both. Quantum computing: (0,0) (0,1) (1,0) (1,1). It basically makes things more probable or makes simple code more complex and bigger.

Also, using quantum entanglement to transmit information FASTER than the speed of light is still science fiction. No one know if this is even possible and many believe that it is NOT possible.

This video is very helpful, informative and creates a positive thinking. Quantum computing theory explained well.thank you

Im in IT and I love standard computers because you tell them what to do, always! Once you start letting computers think for themselves? George Orwells predictions come to mind.

145 people who understand quantum computers disliked this video.

I got to 10:04. When does the 10 minute explamation begin?

The reason why the quantum computer had that high winning rate is because the game was played in its world. Secondly, it has full control over its world and knows how to get what it wants with what it has. Hence, it will always win any game it plays. That is one major problem of humanity. Lack of absolute control over our world due to very high uncertainty about the future. That is why we plan but may still not achieve the desired target due to unforeseen circumstances. This technology has so much potential!!!

She was like my maths teacher I was following it easily till heads and tail the moment I look away and look back the topic gone to legend level

This is not an explanation.

When you show up to the first day of class and the professor expects that you already read and understood the first chapter then quickly summarizes the second chapter to start class discussion.

Best video on quantum computer,made it easy to picture, good work

thank you Shohini Ghose for this wonderful talk !

So where does Quantum leap come into it? Used to love that programme 🤔

"I have access to a 5 Qubit computer, but I used it to run a coin flipping game for which I knew the result." Oh and I gathered participant data that I knew meant nothing...

This is the best TED talk I have heard in Tech

the end of the speech is really beautiful

My cat, "We need to have a good talk about this box and that mouse...." Me, "The box, the mouse...or both." Cat, "What did I just watch?"

Do not waste time on this. The coin flip game is a bad and wrong way to explain QC. I do not like the Schrödinger cat either but it makes more sense than this.

From 9:16 to 9:56 the words hit in my hearth and give burst of ignition in nerves! Yes The Universe is amazing and beyond our imagination. Informations, secrets are openly hiding but we can't access it for our limitations. Hopefully the more we make our brain active the more we get the existence of creativity to unlock the mysteries of Universe!

Excellent Insight from Classical Practicality to Quantum Reality ; Thanks in advance for updating the present status of your Q Internet research endeavor Thanks TED

Ohhhh, so it cheats! "No, no I didn't pick heads, I meant to say tails!" (I've thought of this when I was 3)

Wonderful!. Quantum physics is a panacea for all our security and trust issues of today's computing/internet/digital world!!

Complex Information in laymon language. Great work. Very helpful for an idea of Quantum computing.

The Q-computer prepares the initial state as |Head> and plays first by choosing either to flip the coin or not, but the outcome is not revealed to the opponent - not even to itself! The opponent plays in the second place akin to the Q-computer. Finally, the Q-computer plays, which is also a measurement revealing the outcome … it’s |Head> and hence, the Q-computer wins, not once, but in every round of the game. *** If the opponent plays first choosing the |Tail>, then obviously, the Q-computer loses every round of the game … which is not all mentioned in this video presentation!!! *** |Head> is like the |y; spin-up> state, prepared initially by filtering it out from the Stern-Gerlach (SG) apparatus with magnetic field direction along Y-axis, by blocking the |y; spin-down> component. The |y; spin-up> state then passes through two sequential SG apparatuses [1], but without undergoing any measurement. The magnetic field directions in these two SG apparatuses can be arbitrary. The output from the 2nd SG apparatus is subjected to a measurement by the Q-computer using the final SG apparatus with magnetic field direction along Y-axis, akin to the initial SG apparatus. It’s very clear from the quantum formalism that the two sequential SG apparatuses in between the initial and final SG apparatuses, simply play the roles of identity operators [1], i.e., every time the |y; spin-up> state passes-out of any one of the two sequential SG apparatuses, it’s in the same |y; spin-up> state and hence, the final measurement obviously results in the |y; spin-up> state. Actually, the presence or absence of the in-between two SG apparatuses doesn't matter, because, they don’t perform any measurement. Therefore, the play of Q-computer and the play of opponent are just dubious. In fact, in the case discussed in this video, the Q-computer never performed any quantum computation for winning every round of the game. In other words, it's a game played by the Q-computer with itself = A self-goal (OR) the opponent must be an ignorant to loose every round of the game, because, when the Q-computer shows the initial state, then that's the state to be bet for a win. Reference [1] J.J. Sakurai, Modern Quantum Mechanics, p 33 (Addison Wesley, 1994).

Very nice indeed. The computer does not tell you what happens in between. But it makes sure to display the final result to be heads. I could design such a computer without the super conductors that ibm use :-)

OK fine, 10 minutes was like Antman movie "Do you put quantum infront of everything else"

‘If you’re confused don’t worry you’re getting it’ is really an underrated joke herr

thank you for the explanation ...

Let me explain quantum computing in less then 10 seconds: It’s basically a digital ouija board.

"The future is fundamentally uncertain and that is certainly exciting for me"

For what I've understand the game just gives emphasis on the super-position. So in the first flip it doesn't let go any of the two outcomes, rather hold on to both of them via superposition. Since the computer kept that in super-postion the players choice will also be in superposition. And in the last move computer just boosts the head probability so the computer wins

Very nice presentation about something that interested me nowadays as an engineer .... can you tell me please what was the algorithm used to resolve the coin game you presented or where I can find something written about it .... just to have an example how the quantum computer resolve it !! Thanks a lot .

So if I understand this correctly (which I very well may not), in a game of chance where the rules are determined by laws we understand and can observe, a machine with quantum properties can manipulate the variable outcome by deconstructing and then reconstructing the matter upon which the variable relies to produce a definitive result? Basically what I'm asking is in a game of quarter toss, does the quantum computer dismantle and then reassemble the quarter so that it's always facing up?

1. Quantum computers. 2. Pocket Nukes. 3. End of it all.

Fantastic explanation!

Excellent talk. Thank you

So what you are saying is quantum is all about uncertainty. I got it. A mad computer.

I must appreciate Dr Ghose she explained quantum in a very simple way.

A ted talk that's actually interesting?! That's rare.

The exact explanation of quantum computing is beyond our logic!!!!!😶😶😶

Just one of best times to live, great Talk.

Clear explanation! Now I can see the IBM's quantum computer is different from current ones. What does computer use for doing calculation ? LSI?

That doesnt really explain it... and the computer "checks" for user result to change his.... wtf?

This spectacular example of quantum computing is... the computer can change its answer. That's not quantum anything.

Amazing talk! Brilliant

She’s so smart and her love for knowledge is so endearing. Awesome.

I do realize that quantum computers can do amazing things, but winning that game - that was cheating. It changed the rules so it would always be able to win.

Who came here after Google quantum supremacy?