Introduction to Quantum Computing

This video is an introduction to Quantum Computing!

Quirk Quantum Simulator:

IBM Quantum Experience:

IBM Quantum Computer image from Wikipedia.

Software used to make this vid:

Gimp:

Blender:

Audacity:

OBS:

Davinci Resolve 16:

OpenOffice:

[NStripleseven]

With simpler circuitboards, if you touch them wrong they break. With quantum computers, if you look at them funny they break.

[ShinigamiGrin]

I have only recently discovered your channel. I love every video and that old school style, please never change and keep up the great work, one of the best channels on the whole YouTube as far as I’m concerned.

[willofirony]

So, I was labouring under the illusion that instead of a CPU, the quantum computer had a black cat in a box at the centre. Now I learn that in fact it is so much weirder. Instead, it is super parallel i.e. it computes all possible paths at once. All you have to do is know which result is the right one. How do you know which result is correct? You run the problem through a classic computer first but you will find the quantum computers is quicker. So much simpler than trying to get a black cat to go into a box. Great video. No sarcasm or irony implied, I really enjoyed it. Stay healthy, guys.

[biodevm]

Just one Word for this explanation: AMAZING!

Everyone in Computer Science should watch it.

I'll be recommending it to all my friends and colleagues.

Thanks.

[wessmall]

Basically, in classical computing, your input is deterministic, so your output is deterministic. No matter how many times you read the output, it is the same because the input is the same. In quantum computing, your input is not deterministic, so every time you read the output, it is also different. This means repeated reading of the output will give you a distribution of all possible outputs given all possible inputs. The useful output of a quantum computer is a distribution.

[him]

And I must also commend the (I assume blender?) animations. A far cry from the monophonic assembler tutes of old (but they were good too!)

[jackstephen]

This is by far the best video for explaining this, its weird to get your head round but actually is very simple logically.

[lythd]

Wow ive watched a few of your videos so far, honsetly super impressed, easily my new favourite computer science channel. Honestly seems like you should have more subscribers, your videos are such good quality and so interesting. I wish I found this channel earlier but im just glad I found it :D Cant wait to finish binging a lot of your videos

[monkey_see_monkey_do]

Probably I would skip watching if this was explained by someone else, but YOU explain so clear that even 5 year old kid would get it. I've enjoyed watching how deeply you've dived into this stuff. THANKS FOR EXPLANATIONS AND DEMONSTRATION!

[him]

Scrap my suggestion from last video this is a very good topic - an inspired thought!

[mrlucasftw]

Tech Support Call in 2050 - So, you're quantum computer isn't working? Have you tried turning it off and on again?

[kevnar]

12 years ago, I was listening to the radio, and they had a computer science professor on answering callers' questions. I called in to ask about how far off until we have quantum computers. He laughed and mockingly told the audience that it's a fantasy some people believe in but it will never happen. But here we are.

Quick question to resolve ambiguity - at 8:00 it was never mentioned that the example suggests dependant probabilities of the bits - i.e. the probability of one Q-bit is different depending on the value decided for the other. Is this an oversight or does this actually occur in quantum computers?

[AB-ubnd]

So what’s an actual practical algorithm and how does it compare to a traditional one. So far, i have yet to see a instance of a practical application. The theory is nice don’t get me wrong but show me the money

[Concentrum]

great vid & animations! would love to see more quantum computing content!

[henryseldon]

In your example of using cubits to go through a maze, it demonstrates parallel processing, not quantum computing. Quantum computers would return all possible solutions by treating each cubit as a simultaneous process, not a separate process. It's almost like there is only one cubit in multiple places at multiple times so that no matter how many cubits are used they are all the same cubit in a super position of possible outcomes. Is this right?

[joaq]

I just saw this video last night and you had me in the morning logging into IBM! You can build circuits and do some Python stuff. I see all these gates but I don't understand what is the purpose of rotating the cubits, from a programming point of view. All I have learned so far (tested) is that if you don't run the Hadamard Gate (Superposition) you don't get a balanced result, but like 98% 0s and 2% 1s. I really would be great if you do a series of solving some simple but interesting math problems with the QComputer using Pyhton (I don't like Python that much and I believe it is neither your favorite language but that's what they offer). If you don't do the series, which book would you recommend for an intermediate/veteran programmer but really ignorant about Quantum Computers. Thanks again for another great video!

[amihart]

If the qubits/particles were in all states at once then you could run the program once and get the answer, but you can't, you have to run it dozens of times, sometimes hundreds or even thousands, because it really isn't in all states at once. The wave function does not represent a real physical state but is only visible when you have ensembles of qubits or particles or whatever and add together all the possible paths/values they can take on. Saying that a qubit can be in multiple states at once because ensembles of qubits can have many different values is like saying a coin is both heads and tails at once because if you have an ensemble of coin flips the probability distribution converges towards 50% heads and 50% tails. The reason you can do things like amplify desired results comes down to quantum nonlocality. Qubits can affect all other qubits at once without needing a medium allowing for much more efficient information processing than could be done classically, the CHSH game is a prime example of how this works in action. Qubits still only are ever in one place at a time, they can just interact with other qubits that are in another place.

[nicholas]

Does this mean I can continue to use branching for my applications?

[faisalee]

Awesome! Learned what a quantum computer really is! Every scifi movie has a reference to these, well not every but most of them, and I am pretty sure they don't know what it really is 😀