What are they doing about error correction? Not that it makes this any less impressive (everything starts somewhere), are they simply ignoring the problem?
IBM Q system in development with working 50 qubit processor
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Re: IBM Q system in development with working 50 qubit processor
#22At what point do we no longer trust public key cryptography (RSA)? Where's the break point?
If I remember correctly, it takes a quantum computer with roughly 2N qubits to break N-bit RSA. So we should be ok until thousand-qubit systems are being developed. Increasing key lengths is a short-term workaround, but the real solution is post-quantum public key encryption, which is currently an area of active research.
Do you know what the implications are for symmetric ciphers or [elliptic curve] Diffie-Hellman key exchange? I.e. will forward secrecy still hold up against such future quantum computing?
Re: IBM Q system in development with working 50 qubit processor
#23The article appears to be saying that they are offering an actual quantum computer as a service, but as I recall, their previous offering was a simulation of a quantum computing environment. Yet, this same article refers to that thing as if it were a real QC. This makes me skeptical that the thing being offered here is a real quantum computer...Anyone here have any insight into whether this is legitimate?
The last news from IBM on HN about their quantum offering was that they had optimised the memory required for simulating quantum computers. 50-qubits seemed to the the upper limit before, but they managed to simulate a 56-qubit circuit. It was a good read: https://arxiv.org/abs/1710.05867
They've had real hardware for a while, though, and they have 5-qubit and 16-qubit machines that anyone can try via IBM Q experience.
So this is 100% legit as far as I'm concerned.
Re: IBM Q system in development with working 50 qubit processor
#24The article appears to be saying that they are offering an actual quantum computer as a service, but as I recall, their previous offering was a simulation of a quantum computing environment. Yet, this same article refers to that thing as if it were a real QC. This makes me skeptical that the thing being offered here is a real quantum computer...Anyone here have any insight into whether this is legitimate?
Not an expert, but I do find some of the phrasing weird. Early on they talk about improvements to connectivity and packaging, which would seem to only be relevant to real, live, physical quantum computers. There's also the professor talking about having students run programs on real quantum computers, without any qualifiers (that were included here, anyway) about how it's actually a simulation. Later it talks about software tools, including a Jupyter notebook for heaven's sake, without mentioning the vast gulf between that and what they seem to claim at the top of the article. I'm tempted to say that the author of this press release simply doesn't understand the difference.
Re: IBM Q system in development with working 50 qubit processor
#25The article appears to be saying that they are offering an actual quantum computer as a service, but as I recall, their previous offering was a simulation of a quantum computing environment. Yet, this same article refers to that thing as if it were a real QC. This makes me skeptical that the thing being offered here is a real quantum computer...Anyone here have any insight into whether this is legitimate?
Their previous offerings have been 2 physical quantum computers that can be accessed over the cloud. One with 5 qubits, and another with 16 qubits[0]. These computers have had thousands of users who have run millions of quantum algorithms [1].
[0]: https://www-03.ibm.com/press/us/en/pressrelease/52403.wss
[1]:https://www.engadget.com/2017/11/10/ibm-50-qubit-quantum-com...
Re: IBM Q system in development with working 50 qubit processor
#26Earlier quoted context omitted.
IBM isn't a software-only company: they do research in advanced materials and semiconductor physics, low-level computer architecture, integrated circuit testing, and so on. When you look at the bigger picture, IBM Research has been doing amazing things.
What stands out to you in the last 20 years?
IBM has been awarded more patents per year than any other company for the last 24 years[1]. In 2016 alone, IBM published ~22 patents per day, and ended up being ~2500 patents ahead of Samsung (#2).
[1]: http://www-03.ibm.com/press/us/en/pressrelease/51353.wss
Re: IBM Q system in development with working 50 qubit processor
#27Earlier quoted context omitted.
It's interesting to imagine what connected planet with no reliable encryption would be like. Although I guess we can always fall back on one-time pads.
Quantum computers don't break all encryption. There's no risk of that, fortunately.
Please expand on that. What encryption is vulnerable and what isn't?
Re: IBM Q system in development with working 50 qubit processor
#28At what point do we no longer trust public key cryptography (RSA)? Where's the break point?
It's interesting to imagine what connected planet with no reliable encryption would be like. Although I guess we can always fall back on one-time pads.
> It's interesting to imagine what connected planet with no reliable encryption would be like.
How do you know we're not already living on such a planet?
Re: IBM Q system in development with working 50 qubit processor
#29Earlier quoted context omitted.
If I remember correctly, it takes a quantum computer with roughly 2N qubits to break N-bit RSA. So we should be ok until thousand-qubit systems are being developed. Increasing key lengths is a short-term workaround, but the real solution is post-quantum public key encryption, which is currently an area of active research.
Do you know what the implications are for symmetric ciphers or [elliptic curve] Diffie-Hellman key exchange? I.e. will forward secrecy still hold up against such future quantum computing?
The implication for symmetric ciphers is that key lengths will need to be doubled. 128-bit ciphers like standard AES have 64-bit security against a quantum attack. I expect to see 256-bit keys adopted widely in the not-too-distant future.
I don't know off the top of my head what the implication for key exchange would be, but I know that anything that depends on the discrete logarithm problem for security is vulnerable to a quantum attack. I believe that includes all forms of Diffie-Hellman.
Re: IBM Q system in development with working 50 qubit processor
#30Earlier quoted context omitted.
Quantum computers don't break all encryption. There's no risk of that, fortunately.
Please expand on that. What encryption is vulnerable and what isn't?
I don't know a lot about it, only just enough to know what search term to look for, and Wikipedia had an article that probably fits the bill: https://en.m.wikipedia.org/wiki/Post-quantum_cryptography