Hi Reddit!

We are James Wootton and Frank Harkins from IBM Quantum. We work on educational resources for Qiskit, including our free and open-source textbook.

We just released the beta for a fancy new version of the textbook, including a new introductory course targeted at complete beginners. These are the links we are here to plug, so be sure to check then out! As us anything about quantum computing education! We’ll be answering with /u/Qiskit.

Proof:

Comments: 226 • Responses: 67  • Date: 

_Incorrect_94 karma

What are the most exciting calculations that the field of quantum computing hopes to overcome that will have direct ramifications for the average individual? Put another way, do you see quantum computing being useful for more accurately modeling specific complex systems that we currently use more traditional computational methods to approximate (e.g. FEM, weather prediction, etc...)

Secondly, do you see quantum approaches being useful in the acceleration of artificial intelligence and machine learning (AI/ML)?

qiskit85 karma

This is quite difficult, we won't know for sure until the technology gets there, but I imagine physics / chemistry simulations will probably have the biggest positive effect on individuals. There are thousands of proposed applications to all sorts of different cases but it's difficult at a glance to know which will actually be useful and which are just noise.

I don't know much about AI/ML and what challenges it currently faces, but there is definitely a lot of research in that area. You might be able to read more about some of the algorithms here.

-- Frank

_Incorrect_20 karma

What areas look the most promising right now from your perspective? When you say physics and chemistry, what stands out now? Are things like protine folding possible in the trajectory, or is it really too early to tell?

qiskit43 karma

I know this will be unsatisfying but I honestly can't tell. At some point, we can guarantee some kind of speed up for things like protein folding through Grover's algorithm, but the computers will need to have millions of error-corrected logical qubits to out-perform current classical computers (unless some smart people work out a better quantum algorithm).

There are a lot of heuristic quantum algorithms coming out that claim to work better on noisy devices, but many have no guaranteed speedup, so we don't know for sure until we run them on a big enough computer if they're actually useful.

Something I forgot to mention was that random number generation could also be a contender for an early use-case (and I actually have a source for this one).

-- Frank

Bloubelade4 karma

Could one day AI powered by Quantum Computing solve the climate change problem by inventing something we could not otherwise have thought about ?

qiskit11 karma

From what I understand, AI tends to be best suited to very specific tasks (e.g. image recognition), and I haven't seen any examples of AI that can think laterally like that. I hope that things like physics and chemistry simulations might be used by researchers to help create more environmentally friendly technology (think slightly more efficient solar panels or lower-energy chips), but we're not at that stage yet, and it won't be a silver bullet.

To live sustainably, we will need to drastically change our society to consume less and to use more sustainable alternatives. I don't think there will be any magic technology solution.

-- Frank

kin20c74 karma

Can you please provide a brief introduction to quantum computers for someone totally new to this field?

qiskit174 karma

I think that a lot of people don't think too deeply about what normal computers are, so it's good to start there.

At a simple level, a computer takes in information, processes it and then spits out other information.

In a normal digital computer, that information is expressed in binary: so rewritten in an alphabet of zeros and ones. The processing is done by algorithms, but these are all compiled down to simple operations at the level of bits. Such as the AND operation, which checks if two bits are both 1, and outputs a 1 if they are. With lots of these basic 'atoms of computation', as I call them, you get a computer.

The first section of our textbook is called 'The Atoms of Computation' for this reason, and aims to show that a lot of these basic facts are true for quantum computers too. They are still about processing information expressed in binary.

The difference is that the bits are implemented in a different way. They are not just some simple voltage that is high or low. Instead they are implemented with a an object that obeys quantum mechanics. Various objects can be used (we use superconducting circuits at IBM Quantum). The important thing is just that it is a system described by quantum mechanics, and that you can find a pair of states to store a 0 and 1.'

The fact that it is described by quantum means that you have more basic manipulations that you can compile your algorithm down to. You can make use of quantum effects such as superposition and entanglement. And its been shown that this allows algorithms to be designed in completely different ways, and solve some problems much much faster than conventional computers could ever dream of.

I've gone well beyond your brief of being brief now, so I'm going to stop. Hope that helps!

--James

edit: boolean logical error

tchaffee72 karma

You sure about the output of that AND operation?

qiskit23 karma

You're right, it was NOT AND.

edit: embarrassing typo

ee3k3 karma

so, back in the old "valve and vacuum tube" days of computers, the same could be said to be true, where voltage levels could corollate to different detectable outputs.

is this a case of "whats old is new again" like where people were convinved decades old mainframe and terminal systems were a shiny new idea called "the cloud"?

i mean apart from multiple potential read states (but which are destructively read, if i understand that correctly?), which is nothing exactly new, does it offer?

Edit: re-read that and it sounds kind of rude/aggressive, sorry, not intentional, just kind of how i would have asked the question at work.

qiskit2 karma

In quantum mechanics there is a thing called wave-particle duality. Quantum systems can be both full discrete, and fully continuous. In computation this manifests as a kind of analogue/digital duality. You get the benefits of digital (being able to detect and correct for erroneous deviations) as well as the subtlety of analogue.

Another way to think of the difference between bits and qubits is that there is only one way to ask a bit whether it is 0 or 1. But for qubits there are multiple ways, and the answer you get depends on which you use. And the correlations you see between qubits will also depend on which you use. To the extent that, because there are an exponential number of difference choices you can make for a set of qubits, you also need an exponential amount of information to keep track of all those correlations. That's why simulating qubits is so difficult.

--James

IamCueball36 karma

How do you compare IBM focusing on superconducting qubits while there are other companies focusing on semiconductor and ion traps? Was there a reasoning behind this decision? (Particularly about scalability)

qiskit48 karma

I'm still more of a scientist than a corporate shill (or at least I hope I am) so I'm still very interesting in seeing multiple approaches being taken. There's still a lot of fundamental physics to discover from learning how to isolate and manipulate a good qubit from different quantum systems.

At IBM Research we also maintain enough curiosity to look into other approaches, at least in a more limited way. We are part of a consortium in Switzerland (I'm at IBM Research - Zurich) that looks into spin qubits, for example.

Nevertheless, superconducting qubits show great potential for scalability and allow us to commit to a firm roadmap for building ever bigger devices. So they are definitely our main focus.

--James

IamCueball16 karma

Thanks James. Also, can you please mention the details of the consortium in Switzerland? I am in my graduate studies in Europe and would love to explore opportunities :)

qiskit13 karma

It's the NCCR SPIN.

--James

Heavy-Abbreviations29 karma

We normally model computers as turning machines or lambda calculus. Is there such a model for quantum computers?

Or to ask another way, what does the most basic, complete quantum API look like? What are the functions/classes, inputs and outputs?

qiskit36 karma

Quantum Turing machines do exist, and James wrote this nice piece about how we prove certain sets of operations are universal. If you pick a universal set of quantum gates, that would be your most basic, complete set of instructions. In this model, the inputs and outputs are qubits.

-- Frank

Heavy-Abbreviations7 karma

Thanks for answering Frank!

Maybe I can put it another way, but don’t the inputs and outputs need to be classical to be useful? Like Shor’s algorithm solves a problem that has no quantum in its description (integer factorization.)

I assume you need a function to construct a qubit, what would the inputs be to that function? And likewise, you need some way to read out the result at the end, so presumably there’s a function that takes a qubit and spits out something classical, like a number or true/false. With those two functions you could create and read quints, but nothing else. So you need a function to manipulate a qubit in a controlled way. What would those functions look like?

qiskit14 karma

So, when you measure the qubits you get a string of bits (e.g. 0110101111111100101), and the probability of getting different strings depends on the state of your qubits. The quantum algorithms often prepare the qubits into some known starting state. Then a classical computer works out how to apply the quantum gates so that we have a good chance of measuring a bit string that tells us something useful.

For example, with Shor's algorithm, the qubits will start in the same (or very similar) states for any input number, but the operations will be different. You need the universal operations to get the qubits from the starting state to the useful end state, but in this case a classical function takes the problem number as input and works out which operations to apply. When we measure, we get some information about the number's factors.

Hope that makes sense

-- Frank

fmaz00818 karma

Is Quantum computing a threat to Internet Security and Crypto currency?

As in: could it bruteforce most algorythms currently in use, rendering them useless?

qiskit16 karma

So in theory yes, a lot of internet security is based around RSA encryption), which relies on the fact that it's too difficult (i.e. essentially impossible) to factor large numbers, even with incredibly powerful computers. One of the famous algorithms in quantum computing is Shor's algorithm that, once we have big enough quantum computers, should be able to manage the task (I wouldn't call this 'brute forcing', it's actually the opposite). One estimate reckons around 20 million qubits are needed to break the encryption most of us use today.

If we're still all using RSA encryption at that point, then yes- some internet security will be vulnerable. There is a lot of research into post-quantum cryptography that will hopefully not be susceptible to quantum attacks. Since I don't really understand current cryptography, I've no idea how well they're doing with it.

-- Frank

Haemly4 karma

I often hear the argument that we have new encryption algorithms that are ready for the quantum age, and will implement them when needed.

But at what point should they be implemented? If we wait until they are required, then it might be too late? I understand that we may be a while away yet, but couldn't some break-through cause a lot of problems if fallen into the wrong hands?

qiskit5 karma

New standards should ideally be in place well before QCs break anything. We've likely still got at least a decade before then, though, but that means nows the time to sort it all out. And people are indeed doing just that, including some of my colleagues.

--James

Datacruncha2 karma

When you say big enough quantum computers, are you referring to the physical size?

qiskit2 karma

The number of qubits is usually what is meant when people speak of the size of a quantum computer. What that means in terms of physical size depends on how the quantum computer is built.

--James

unacceptabbble16 karma

What technology in the near future may carry quantum system, for example phones, internet etc..?

qiskit34 karma

For the relatively-far future I would imagine quantum computers will remain large machines in labs accessible via the cloud. Quantum algorithms generally only become advantageous if you've got a really big problem that you can't break down (e.g. factoring a huge number for cryptography reasons) instead of lots of tiny problems (e.g. raytracing). A lot of the predicted use-cases will be reducing computation times from years to hours instead of seconds to milliseconds.

-- Frank

MichiRecRoom14 karma

This might be a silly question... what would you say is the quantum computer equivalent of a "Hello World" program?

qiskit11 karma

People often use the creation of a Bell pair as the 'Hello World' which looks something like this.

qc = QuantumCircuit(2,2)
qc.h(range(2))
qc.cx(0,1)

It basically spits out 2 bit strings that will randomly be either 00 or 11. Pretty simple as a quantum program, but it requires the device to do all the basic features of quantum systems (superposition and entanglement). uilding a device that'll do just this is something that could win you a Nobel prize at one point!

--James

edit: following orders from /u/backtickbot

jake_boxer5 karma

Could you explain what the h and cx abbreviations stand for? I’m super interested in this question, but it’s a little hard to understand the answer with these method names abbreviated.

qiskit2 karma

Good point. The h is something you can do to a single qubit. It creates a superposition state of 0 and 1. So if you just look at that qubit straight away, it will randomly give you a 0 or 1. The cx is a so-called 'controlled-NOT'. This acts on two qubits, effectively looking at the first to see if it is in 1 state. If it is, the cx flips the other qubit (from 0 to 1 or 1 to 0).

In this case you use the h on one qubit, and then use that as the control of the cx. This effectively spreads the randomness over both qubits, giving the random 00 or 11 I mentioned before.

--James

jake_boxer3 karma

This makes a lot of sense! Thank you so much for the detailed explanation.

Out of curiosity, what do the h and cx actually stand for?

qiskit2 karma

The h is for Hadamard, since this gate performs a single qubit Hadamard transformation. The x is a quantum gate that has the effect of a flipping a qubit (so like a classical NOT) and the cx is a controlled version of x.

onepluse2theitimespi13 karma

Thank you for the textbook! I took an Intro to Quantum Computing class last spring as part of my Master's and the Qiskit textbook was bookmarked and read religiously - I actually found it better to use (especially for applied programming concepts like algorithms) than the textbook we used in the class. The explanations and implementations of multiple Q algorithms were really entertaining to play with.

That being said, I finished working through the Qiskit textbook. Is there anything you would recommend doing after that, or any information you feel is essential in the field that isn't covered in the textbook? I'm really interested in researching something quantum related for a thesis, but I'm not sure exactly what to do at this point.

qiskit12 karma

The textbook is very focussed on quantum computation, and is currently missing a lot of more general quantum information topics such as discussions of Von Neumann entropies (everything that uses them). There are great resources for these in Preskill's notes.

There is also not enough on quantum error correction, with the lack of a surface code chapter being a big gap. I have an ancient set of blogs about that, (which the repetition code chapter in the textbook was based on. You can see the rest of it here.

--James

TurbulentTable12 karma

Are quantum computers only going to be a niche product/market or is there some hope that they could revolutionize the personal computing world?

qiskit27 karma

They're unlikely to change personal computers for a very long time, if ever. Quantum algorithms tend to speed things up from years to hours instead of seconds to milliseconds. Most personal computers don't encounter problems that take years, so for now they'll be mostly used by industry or researchers for problems that they have to use large computer clusters for (or can't even attempt at all).

-- Frank

kmonsen9 karma

Isn't this what someone would say about computers in the mainframe age? I'm sure all the data points to what you are saying, but still feel it is way too early to say how quantum computers will be used (if at all) 50 years from now.

qiskit6 karma

That's true! -- Frank

dvs2411 karma

What do you think about photonic based QCs? They leverage a lot from existing infrastructure, why don’t everybody pursue the QC this way?

Secondly, of the QCs are meant to solve the certain subset of problems, why would we need the universal computer and not stick to quantum annealers instead?

qiskit18 karma

Every QC will have to develop a lot of new infrastructure, even if it uses some existing stuff, so I don't see that as a huge advange.

For universal QC, the motivation is usually the problems that annealers can't deal with rather than the ones they can. I would expect that dedicated annealing hardware would probably be better at those specific problems if enough effort is put in to developing them. But there is more potential gain from putting effort into the universal approach.

--James

edit: adding name

notvortexes10 karma

Hi, I am entering a PhD in Physics this year. Do you have any advice to maintain general skills in quantum information applicable widely across the industry? Working on hardware I will need to specialize in one specific type of qubit (e.g trapped ions). I would like to remain employable in the quantum computing industry regardless of which type of qubit becomes the front runner. Is learning qiskit and other quantum programming languages enough to ensure career options in quantum software?

qiskit9 karma

In our Qiskit stack we have Open Pulse, which is designed to be compatible with any system that obeys the rotating wave approximation, which is fairly general. All the higher level stuff (gates and algorithms) are all in the universal language of quantum computing, so are also broadly applicable.

Of course, the IBM Quantum focus on superconducting qubits will lead to biases creeping in. Such as designing things assuming that the qubits are sitting on a chip with a given coupling map. But it is nevertheless fairly general.

So I think that excelling at Qiskit or any of the other frameworks will give you what you need.

--James

Mob_Rules19948 karma

How much does a quantum computer go for these days?

qiskit12 karma

Actually buying one would cost more money than I'll ever have. But they are more likely to be a cloud service. And access to some of our devices is free for everyone!

--James

First-Reach70276 karma

Ok this might sound silly. But if someone wanted to develope a video game for a quantum computer what advantages he will get compared to traditional ones and how would that affect the games? Would they be better? I know quantum computers are not for video games, but I couldn't help but wonder.

qiskit2 karma

Not silly at all!

This has been asked a few times so I'm afraid you are getting a copy/paste...

I've been looking into how quantum computers might be used for games. First it's important to stress that you won't be sending a task to a QC every frame.

I think the most likely option is to outsource some tasks in procedural generation to them (see this blog post). The QC could be used for anything from generating noise functions (for terrain generation) to solving constraint satisfiability problems (for generating levels that satisfy constraints like being completable). All this could be done during a loading screen, or even during game design, so the time taken to sumbit the quantum job over the cloud won't be a problem.

Also people have made simple games for them for educational purposes or to demo the technology (in much the same way as games for conventional computers in the 1950s). I think this is a great thing people can do to get their first taste of quantum, and we've even made a dedicated game engine to help people do it.

I wrote more about this topic in this blog post.

--James

LavishManatee5 karma

I am absolutely enamored with quantum computing and neuroscience. I am currently working in IT but will be going back to school and and majoring in QC is at the top of my list.

In your opinion, where/what/how would you recommend for one to get as much learning material for QC as possible? Any courses, books, video lectures you would recommend? I have already bookmarked the book and intro course you have linked to, thank you so much for that!

I have been studying machine learning programming for about 1 year on my own, I am very interested in quantum machine learning as well.

Thank you for this AMA, btw, this was very educational!

qiskit2 karma

Since you're serious about QC, I recommend "Quantum Computation and Quantum Information" by Isaac Chuang and Michael Nielsen. It's pretty large, but is so popular in the field it's known as "Mike & Ike". People also love John Preskill's notes and I personally like anything by Scott Aaronson.

-- Frank

brownishthunder5 karma

As a software engineer that has looked in to quantum computing quite a bit, how do you the the gap will be bridged so that quantum software can be written by someone who isn't a scientist in the quantum mechanics field?

qiskit7 karma

There are different levels at which quantum software can be developed at used. Writing it at the machine code level will always require some specialist quantum computing knowledge. But there will also be the possibility to just use tools built upon it, and not have to worry about how they do what they do. For example, by using Qiskit's optimization modue.

--James

ReubenDeuben4 karma

IBM recently released it's quantum development roadmap which I find very ambitious but exciting. The only hardware related goals given here are in terms of the number of qubits. However, as we all know, the capability of a quantum computer depends on other hardware parameters such as the noise of one and two-qubit gates (among others). Do you know if IBM has set goals similar to this roadmap that are related to other hardware parameters?

Edit: Perhaps goals relative to the quantum volume...

qiskit4 karma

Yes, IBM is aiming to at least double quantum volume each year (link).

-- Frank

llobotommy4 karma

Quantum computers have been around for some time now. Has the underlying technology / hardware changed much since the first iterations or is the ‘quantum’ in the title more of a grading of the use case for such machines? Disclaimer: I know little to nothing about these things only that they’re on the bleeding edge of tech.

qiskit11 karma

At an abstract level, quantum computers are made of qubits. You need a lot of them to store and process any decent amount of information.

You can try to built a qubit out of basically any quantum system. The challenges are to get them to interact with each other (required to process information) and for them to not be completely crap (required to not be completely crap). So the last few decades have seen a lot of effort in building a few qubits using various methods, trying them out and seeing if they've got what it takes to go the distance.

What we are seeing now is the best approaches are starting to really ramp up the number of qubits, allowing people to actually try doing things with them. And making it worth putting them on the cloud for people to use.

Admittedly the things you can do are pretty simple, since they are still at a prototype stage. But gone are the days when you need a PhD just to poke a single qubit.

--James

edit:speling

llobotommy2 karma

Thank you for the detailed answer. When you say ‘try things with them’, what are the most likely use-cases? Obviously that’s a broad question, but what question do quantum computers answer regular computers can’t cope with?

qiskit8 karma

There have been examples of doing simple chemistry calculations with current devices, and hope that ever more complex quantum chemistry can be done in the near-term.

In my own research (which I hope could serve as a good jumping off point for people trying to get into quantum computing themselves) I'm looking at procedural generation

--James

McJock4 karma

What cruel and unnatural punishment do you reserve for people who pronounce it "Kwiss Kit"?

qiskit9 karma

None remain who know.

--James

notvortexes6 karma

How am I supposed to pronounce it?

qiskit6 karma

I use kizz-kit, but I accept kiss-kit people.

There was an idea at the very beginning that 'cheese-kit' should be the official pronunciation, but that has rightly faded into legend.

--James

Anon89m3 karma

How can quantum computers help with machine learning?

qiskit4 karma

I don't know much about machine learning, but I know there are some algorithms which are expected to speed up in that area. You can read more about some of the algorithms here.

-- Frank

poilsoup23 karma

Oh hey I used qiskit in my quantum computing class.

You have an option (or did last i checked) to simulate quibits so you arent limited by the low bits of the 8-bit physicals systems that were available.

However, these systems didnt simulate error. For example, in your chapter regarding the Deutsch-Jozsa Algorithm, it is correct about 66% of the time. But the simulation would be 100% correct

Is there any work/progress on simulating quantum error to better advance quantum error correction algorithms?

In my time working with it, I also noticed some quantum computers were more error-prone than others.

Are there grades of quantum computers? For example, brown/red/silver/gold resistors indicate the tolerance, do quantum systems have similar ratings for how generally error-prone the quibits or configuration is?

qiskit3 karma

Our simulators do now have the possibility to simulate noise. You can make a noise model, or insert Kraus operators into your circuit. My favourite option is to use the 'fake' versions of backends. So for any of our devices, you can define a fake version which will simulate it with the noise that would be expected from the device's last set of benchmarking data.

For grading of quantum computers, you lose a lot of subtlety in trying to express everything in a simple 1D measure of quality. But nevertheless we have a measure we use: the quantum volume.

--James

Tekko502 karma

Bit late to the party but how will this new way of processing data/computation affect "non quantum" encryption as well as cryptocurrencies? Cause from what I understand the moment you get past a few dozens computation cycles on a handful of qubit nothing would resist even the most basic brute force attack for more then a few seconds/minutes.

qiskit1 karma

If we keep improving the quantum computers at the same rate, at some point we will be able to break RSA encryption, which a lot of the internet uses for security. What you understand is incorrect though, we predict we'll need millions of qubits to start cracking modern encryption, and there's a lot research into finding cryptography that even quantum computers can't break (although I don't know much about that so I've no idea how it's going).

-- Frank

hljodmyndir2 karma

Right now qiskit and quantum computers are very much at the gate level. Do you think in the future there will be higher level quantum programming languages? How similar would high level quantum languages be to our high level classical ones? Would there be different high level primitives for a quantum language?

qiskit6 karma

There's definitely been a lot of work in that direction. Qiskit has a lot of higher-level APIs with this in mind. For example, you can already do something along the lines of Shor(15).run() (see here) . Check out Qiskit nature and machine learning too.

I think in your question though you might be thinking more along the lines of Silq? I don't know much about it but it certainly looks interesting.

- Frank

Readityesterday22 karma

How many q-bits have been achieved by anyone?

Why is it hard to create large q-bits?

qiskit2 karma

So, we could create loads of qubits right now, but if they're not very good then you might as well not have any. At the moment there's more focus on increasing the quality of a few qubits, then we can scale up the numbers once they're good enough.

Quantum computers use quantum effects to compute things, and we only really see these effects in delicate lab experiments with things at the atomic level. You can imagine it's pretty hard to get these delicate things to behave the way we want, but that's what we need to do to build qubits.

-- Frank

_kurip2 karma

what fps would you get on cyberpunk2077 ?

qiskit1 karma

If you've got to send a job to a quantum computer over the cloud for each frame, I'd guess around 1/60 FPS (so one per minute). But using the QC in a loading screen to procedurally generate something could be more worthwhile.

--James

0taries2 karma

Why you guys used the picture of the Ever Given boat location dot for this AMA ??

qiskit2 karma

Reddit seems to have pulled it out of my Twitter.

--James

ronintetsuro2 karma

Does it run Crysis? (Sorry, had to.)

qiskit1 karma

This has been asked a few times so I'm afraid you are getting a copy/paste...

I've been looking into how quantum computers might be used for games. First it's important to stress that you won't be sending a task to a QC every frame.

I think the most likely option is to outsource some tasks in procedural generation to them (see this blog post). The QC could be used for anything from generating noise functions (for terrain generation) to solving constraint satisfiability problems (for generating levels that satisfy constraints like being completable). All this could be done during a loading screen, or even during game design, so the time taken to sumbit the quantum job over the cloud won't be a problem.

Also people have made simple games for them for educational purposes or to demo the technology (in much the same way as games for conventional computers in the 1950s). I think this is a great thing people can do to get their first taste of quantum, and we've even made a dedicated game engine to help people do it.

I wrote more about this topic in this blog post.

--James

ChubyCat2 karma

I did the course that occurred from 2020-2021. Will a more advanced course come out in the future? Also will the quantum machine learning course that occurred over the summer, also be available. I missed that one sadly.

qiskit3 karma

There will always be courses and educational materials being released, so keep checking back. I can't say much about the things that I suspect you'll like, but they are coming ;)

--James

gringer2 karma

How do qubits differ from ternary logic, where the superposition could be modeled as an intermediate state (i.e. 0,-,1)?

qiskit4 karma

There are infinite different superposition states. A single qubit would be captured better by a sphere, with 0 as the north pole, 1 as the south and all other points being different superpositions. Single qubit manipulations are then rotations of the sphere. We use this fact for a popular visualization known as the Bloch sphere.

The trouble is that two qubits can't be described by two spheres, because this would not capture all the different correlations required. Instead, a single 15 dimensional object would be needed. The number of dimensions required increases exponentially with qubit number, so it all gets a bit unmanageable.

--James

Alien-Fox-42 karma

I heard that quantum computers have something like 95% accuracy. Wouldn't this prevent construction of larger quantum computers because more qubits means more chance for error?

qiskit2 karma

We are more like 99% at the moment and getting better. However, for a truly scalable quantum computer we'll need to use quantum error correction (whose overheads will require even bigger quantum computers!).

--James

phi_array2 karma

Are Quantum Computers supposed to be like GPUs with near infinite cores? I’m confused about the “infinite values at once” thinh

qiskit2 karma

Quantum computers take advantage of certain physical phenomena that are too delicate for normal computers. This essentially gives them some extra operations they can use, so they're not directly comparable to normal computers (like GPUs). The effect is called interference and I tried to write about it here without being too hand-wavey.

We only know how to use these tools to our advantage in a handful of situations, and since these phenomena are delicate, building a quantum computer is also a pretty difficult task, so the computers can make lots of mistakes.

You're right to be confused by someone talking about “infinite values at once”, that isn’t really a good explanation of how the technology works.

— Frank

Yoylecake21002 karma

(Joke Question) : Help i forgot the password to my bitcoin wallet, i have half a billion dollars worth in bitcoin in that wallet. ill give you 10% of my wallet's value if you help me crack it

(Serious Question) : if the Quantum Computing revolution (where they become accessable to consumers) ever occur, do we have to rethink how we Encrypt our Data?

qiskit1 karma

Hahaha, if I could crack you bitcoin wallet I would just take it all. (EDIT: actually I wouldn't, that would be a flagrant abuse of quantum computing power.)

But I reckon, yes we will probably need to switch to other methods of encryption. You can read about post quantum cryptography if you're interested.

-- Frank

doge0072 karma

is that something that is accessible to people who like to learn? I have tried some simulated ones, and it was interesting. However, the learning curve for someone who's never been exposed to physics/calculus in-depth is daunting.

qiskit2 karma

This is actually the goal of the intro course we made. The course should at least give you an idea of whether you want to continue learning. If so, you'll want to learn about linear algebra and complex numbers (which are actually pretty interesting in their own right IMO).

-- Frank

Ragdolll2 karma

How many of these do you estimate there is demand for in the world? 5 or so?

qiskit2 karma

We currently have more like 30 on the cloud at the moment, and the demand is for more. And that's before they are even useful for anything ;) So I think Watson's famous (and probably misattributed) prediction for conventional computers doesn't apply to quantum ones either.

--James

pm_me_sum_tits2 karma

Can it run doom tho?

qiskit2 karma

This has been asked a few times so I'm afraid you are getting a copy/paste...

I've been looking into how quantum computers might be used for games. First it's important to stress that you won't be sending a task to a QC every frame.

I think the most likely option is to outsource some tasks in procedural generation to them (see this blog post). The QC could be used for anything from generating noise functions (for terrain generation) to solving constraint satisfiability problems (for generating levels that satisfy constraints like being completable). All this could be done during a loading screen, or even during game design, so the time taken to sumbit the quantum job over the cloud won't be a problem.

Also people have made simple games for them for educational purposes or to demo the technology (in much the same way as games for conventional computers in the 1950s). I think this is a great thing people can do to get their first taste of quantum, and we've even made a dedicated game engine to help people do it.

I wrote more about this topic in this blog post.

--James

winnipeginstinct2 karma

probably (definitely) not what it would be used for, at least for a long while, but could it be used for video games, and would it perform better than a regular computer?

qiskit2 karma

This has been asked a few times so I'm afraid you are getting a copy/paste...

I've been looking into how quantum computers might be used for games. First it's important to stress that you won't be sending a task to a QC every frame.

I think the most likely option is to outsource some tasks in procedural generation to them (see this blog post). The QC could be used for anything from generating noise functions (for terrain generation) to solving constraint satisfiability problems (for generating levels that satisfy constraints like being completable). All this could be done during a loading screen, or even during game design, so the time taken to sumbit the quantum job over the cloud won't be a problem.

Also people have made simple games for them for educational purposes or to demo the technology (in much the same way as games for conventional computers in the 1950s). I think this is a great thing people can do to get their first taste of quantum, and we've even made a dedicated game engine to help people do it.

I wrote more about this topic in this blog post.

--James

Zombi-sexual2 karma

Why is the thumbnail for this the Ever given on Portvision/ vesselfinder?

qiskit2 karma

I was wondering that too!

I think it is because the last link is to my twitter, and the last image I posted on my Twitter was of the final liberation of the Ever Given.

--James

Onlyhereforthelaughs2 karma

Um, a question from an average Joe, does it play games and stuff?

qiskit2 karma

This has been asked a few times so I'm afraid you are getting a copy/paste...

I've been looking into how quantum computers might be used for games. First it's important to stress that you won't be sending a task to a QC every frame.

I think the most likely option is to outsource some tasks in procedural generation to them (see this blog post). The QC could be used for anything from generating noise functions (for terrain generation) to solving constraint satisfiability problems (for generating levels that satisfy constraints like being completable). All this could be done during a loading screen, or even during game design, so the time taken to sumbit the quantum job over the cloud won't be a problem.

Also people have made simple games for them for educational purposes or to demo the technology (in much the same way as games for conventional computers in the 1950s). I think this is a great thing people can do to get their first taste of quantum, and we've even made a dedicated game engine to help people do it.

I wrote more about this topic in this blog post.

--James

Patamonrx2 karma

How much more effective are quantum computers at doing tasks (combinatorics) than traditional computers at a simmilar price range?

qiskit1 karma

The tasks that quantum computers are really targeted are the ones that everyone tries to work around now, since it is completely unfeasible to attempt them with less than a planet-sized supercomputer. So with that in mind, QCs are pretty cheap ;)

Of course, we are not yet at the point of being able to solve such problems with current QCs. We have gone a long way, but we have a long way to go.

--James

wallyslambanger2 karma

Do quantum computers use yardow to send questions back in time to when it was first activated in order to have time to process the answer?

qiskit4 karma

Some of the more imaginative people in quantum information science have looked at indefinite causal order, and worked out fancy things you could do if you have a black hole handy. But mostly we are limited to the normal linear nature of time.

--James

AmigaIZI2 karma

Most importantly, Can you run Doom on a quantum computer ?

qiskit6 karma

You'd need a normal computer to interface with the controls and screen. And since that computer could run Doom by itself, it would just be a question of what jobs you give the quantum computer and why.

I've been looking into using quantum computers for procedural generation. So a Doom mod with procedurally generated levels might be a semi-sensible thing to do with a QC.

--James

qiskit1 karma

This has been asked a few times so I'm afraid you are getting a copy/paste...

I've been looking into how quantum computers might be used for games. First it's important to stress that you won't be sending a task to a QC every frame.

I think the most likely option is to outsource some tasks in procedural generation to them (see this blog post). The QC could be used for anything from generating noise functions (for terrain generation) to solving constraint satisfiability problems (for generating levels that satisfy constraints like being completable). All this could be done during a loading screen, or even during game design, so the time taken to sumbit the quantum job over the cloud won't be a problem.

Also people have made simple games for them for educational purposes or to demo the technology (in much the same way as games for conventional computers in the 1950s). I think this is a great thing people can do to get their first taste of quantum, and we've even made a dedicated game engine to help people do it.

I wrote more about this topic in this blog post.

--James

invasionofsmallcubes2 karma

In terms of personal security (eg. the private key I use to ssh all the things) how should I protect myself from an attack vector that uses a quantum computer?

(Not sure if it makes sense as question, but I'm guessing cryptography will be affected)

qiskit1 karma

Fortunately, you're not at risk yet. Quantum computers are just learning to factor 15 and 21, they won't be able to factor the 2048-bit RSA integers we use for encryption for a while. If you're super paranoid (or interested), you could use longer keys which will postpone the date at which QCs can break them, or start researching into post-quantum cryptography.

(Disclaimer: I am not a security expert so take this with a pinch of salt)

-- Frank

klparrot2 karma

Would you say this competes with, or could be complementary to, or is just really a different thing than what Amazon Braket offers?

qiskit2 karma

They are definitely aiming for the same thing, so it would be fair to say that they are a competitor. But since it's still very much an emerging technology that we are all working on the development of, I'd prefer to think of us as all being on team QC.

--James

JimmyTheHuman2 karma

Do super conductors play a role in quantum computing?

qiskit2 karma

Our qubits (the quantum version of bits at the heart of quantum computers) are made from oscillators in superconducting circuits. Other ways to build qubits might not use superconductors. So the answer (as you might expect from quantum) is yes and no!

--James

liarandathief2 karma

How much would room temperature superconductors change your field?

qiskit3 karma

For our superconducting qubits, I don't think much would change. We still need them to be really, really cold to suppress noise, regardless of the temp required for superconductivity.

For other approaches, for example photonic qubits where superconductors as used in detection devices, I'm sure it would make things easier.

--James

meh6792 karma

I seem to be pretty late to this party but I figure I might as well ask. This isn't a dig at you guys I'm just curious, per your title, how do you help people try out quantum computers? The links you provided are just information on them but if I were to be interested in actual quantum computing how would I actually get into this?

I really hope this doesn't come off as sarcastic or accusatory, I'm just genuinely curious.

Edit: okay admittedly I didn't look into the links thoroughly enough to see the guides on accessing the website providing quantum computing, I guess I'd still be interested in an answer to the question but consider me shorthanded in actually looking through the provided materials

qiskit1 karma

The quick answer to how to actually use a quantum computer is to go to our cloud service here, and click some buttons. Pretty soon you'll be able to make a quantum program and send it to run on one of our real devices.

The trouble is that you probably won't have any idea of what your quantum program does, or why it gives the results it gives. So now the main barrier to entry is not access to the devices, but the knowledge of what to do. That's why we have created our textbook, and why we just launched the new specific learning path for complete newbies.

slugma1231 karma

How can I try Quantum Computers, really?

qiskit1 karma

There's this website where you can just push a few buttons to send a job to one of our quantum computers. But to help you understand what you are doing, that's what our new introductory course is about.

--James

Dizzy_Scar1 karma

Could you game on one of these? If so how would it preform?

qiskit6 karma

I've been looking into how they might be used for games, and I think the most likely option is to outsource some tasks in procedural generation to them (see this blog post).

Also people have made simple games for them for educational purposes or to demo the technology (in much the same way as games for conventional computers in the 1950s). I wrote about all that in this blog post.

--James

Diethkart1 karma

Why do you focus on this unnachievable technology?

qiskit3 karma

Well I don't see it as unachievable, of course. Just challenging enough to be interesting!

--James

Tanro1 karma

When can i expect QC to affect gaming, what kinda fps we talking?

qiskit1 karma

This has been asked a few times so I'm afraid you are getting a copy/paste...

I've been looking into how quantum computers might be used for games. First it's important to stress that you won't be sending a task to a QC every frame.

I think the most likely option is to outsource some tasks in procedural generation to them (see this blog post). The QC could be used for anything from generating noise functions (for terrain generation) to solving constraint satisfiability problems (for generating levels that satisfy constraints like being completable). All this could be done during a loading screen, or even during game design, so the time taken to sumbit the quantum job over the cloud won't be a problem.

Also people have made simple games for them for educational purposes or to demo the technology (in much the same way as games for conventional computers in the 1950s). I think this is a great thing people can do to get their first taste of quantum, and we've even made a dedicated game engine to help people do it.

I wrote more about this topic in this blog post.

--James

TheD1v1s1on50 karma

Is it good for mining bitcoin?

qiskit26 karma

Not now. And by the time quantum computers become useful for relevant cryptographic problems, I would hope that planet burning cryptocurrencies will be long gone.

--James