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Design of a silicon quantum computer chip
- 2_listerine_pls 9y agooushit
- sctb 9y agoPlease comment civilly and substantively or not at all. https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html
- ct520 9y agouh so what does this mean?
- mtgx 9y agoThat we could have quantum computing "accelerators" in our computers and maybe even smartphones by 2030, just like we're starting to see machine learning accelerators now (or GPUs for graphics processing in the 90's).
- matte_black 9y agoSo what kind of stuff can we do with that?
- jcoffland 9y agoNothing significant until we have many more qubits. With 128 qubits you could crack 128 bit RSA encryption in a few mins.
- leecarraher 9y agocitation? A theoretical understanding of bits in quantum superposition would support the notion of traversing all combinatorially related possibilities however that is not the case for any realizable quantum computer. Realizable machines are based on specific quantum logic gates. otherwise you would have to design at the electron level, a new processor for every problem.
- marcosdumay 9y agoHere's the citation: https://en.wikipedia.org/wiki/Shor%27s_algorithm https://en.wikipedia.org/wiki/Shor%27s_algorithm You do need to update yourself. There are standard gates, complete computation theories, and algorithms for lots of interesting problems. Those aren't even new.
- leecarraher 9y agoaes isn't broken by factorization of composites of prime. if the op had said rsa, sure, but they said aes (it was changed you can tell because there was never such a thing as 128bit rsa), but thanks for telling me about that "new" shor's algorithm devised in 1994.
- marcosdumay 9y agoYes, comment edition sometimes leads to misunderstanding. But there was 128bit RSA, it was in use up to the middle of the 00's.
- godelmachine 9y agoWhat would be nice book / video / web link that will give a decent intro to a novice like me?
- qubex 9y agohttp://www.clerro.com/guide/580/quantum-computing-explained http://www.clerro.com/guide/580/quantum-computing-explained
- api 9y agoI've thought for a long time that this explains why the NSA is recording so much encrypted data. When QCs are available they will be able to decrypt all the things. Imagine what they'll learn.
- qubex 9y agoThat’s a bit conspiracy-theorist-ish but unfortunately in the present climate and given that has transpired from the Snowden leaks not at all implausible. Either they have made a breakthrough in number theory that allows factorisation over finite fields, or they have a quantum computer already, or they are banking on having one soon. In any case, storage is so cheap that it makes sense to just record the traffic (which is useful for sigint anyway) and refer back to it “if and when”. Of course, much of what we consider “public-key encrypted” traffic is actually encrypted with a symmetric cipher whose encryption is impervious to Shor’s Algorithm… it is the key-exchange process that really uses the textbook public-key encryption algorithms. So much of the traffic is technically impervious to whatever advances they have made, but of course once you have captured the key-exchange “handshake” that sets up the session and exchanges the symmetric cipher keys, you’re all set to retrieve the plaintext from the intercept. There are public-key algorithms (particularly those based on lattices) that we currently hold to be secure against attack by quantum computers. I am surprised these are not seeing more adoption amongst the “enlightened paranoid cypherpunk elite”. Here is a primer on such “post-quantum cryptography” approaches, courtesy of the good folks at Wikipedia: https://en.wikipedia.org/wiki/Post-quantum_cryptography https://en.wikipedia.org/wiki/Post-quantum_cryptography
- api 9y agoIn the process they'd get key exchanges too and it's easy to correlate traffic. I thought it was a really straightforward obvious idea. I'd do it if I were them and had such deep pockets. QC is clearly coming. Lots of news lately.
- qubex 9y agoI was agreeing with you, of course if they have intercepted all traffic they have both public-key encryption key exchange and the resulting symmetrically encrypted traffic and that they could correlate it... I’m sorry if I was a bit longwinded and pedantic in my reply, I didn’t realise I was talking to virtual Hacker News nobility (with ten times the karma I do!).
- Accipitriform 9y agoOne claim is the near instant factoring of large integers...breaking a class of encryption that's widely used currently.
- vtomole 9y agoQuantum computers can be used to simulate quantum physics and approximate solutions to optimization problems.
- yeahsure 9y agoHonest question: Why would the average person want/need to do that with their smartphone or computer?
- barrkel 9y agoWhy would someone want more than 640k of RAM?
- jamesharrington 9y agoMy thoughts exactly.. We don't know we need it till its to indispensable to remove. Only god knows what we could do with quantum computers. There are some low hanging fruit with encryption and quantum simulation.. but hey maybe it can be used in random world generation for games like minecraft.
- dima_medvedev 9y agoThat's what Ballmer thought about iPhone.
- ajkjk 9y agoThey wouldn't.
- vtomole 9y agoThe average person would probably not find a lot of use from those applications; but researchers will.
- deleted 9y ago[deleted]
- ajkjk 9y agoYou can't just casually assume we'll suddenly figure out how to run qubits at room temperature in 13 years.
- qubex 9y agoUh finally! Thanks for explicating this so succinctly and adroitly. I'm driven spare by the “quantum computers everywhere [because] Moore's Law bla bla bla” attitude.
- detaro 9y agoFor clarification for other readers, the authors of the paper here do not make any claim towards that. They assume a setup where > the complete structure is maintained at cryogenic temperatures (∼1 K or less) inside an electron spin resonance (ESR) system, which will be used to apply qubit control pulses.
- qubex 9y agoThe authors don’t, but the previous post (apparently) implicitly assumes it (or fails to understand what maintaining quantum coherence entails, or both).
- gaze 9y agonot all that much unless you're in the field, in which case it's pretty cool.
- stevemk14ebr 9y agoDoes anyone know if this is just marketing or if they've actually solved the technical problem. If they have solved it, what's the ETA (months, years, decades)?
- mtgx 9y agoETA 2022 until a 10-qubit silicon quantum computer prototype is made. I doubt it's just marketing. UNSW is the leading university in researching silicon quantum computers and one of the best in researching quantum computers in general, too.
- jcoffland 9y agoYou cannot do anything interesting with 10 qubits. Anything you can do with 10 qubits will likely be faster on conventional computers. IBM says you need at least 50 before it gets interesting.
- philipov 9y agoWhat interesting things happen at 50 qubits?
- mtgx 9y agoWe can prove that quantum computers are faster than classical computers at solving certain problems (like simulating atom interactions). Although IBM recently moved that goal post, and proved that we can simulate 56-qubit (and probably a little more than that) with classical supercomputers. https://spectrum.ieee.org/tech-talk/computing/hardware/ibms-quantum-leap-simulates-56qubit-machine https://spectrum.ieee.org/tech-talk/computing/hardware/ibms-...
- mathgenius 9y agoIt's debatable how generic this 56-qubit simulation is. We can already "simulate" millions of qubits, with entanglement, as long as they dance in a particular way...
- visarga 9y agoI, too, have a complete design for the warp engine in my basement.
- narrator 9y agoDoes this require freezing the chip to near absolute zero like existing designs?
- vtomole 9y agoYes it does. From the paper: "We assume that the complete structure is maintained at cryogenic temperatures (∼1 K or less) inside an electron spin resonance (ESR) system, which will be used to apply qubit control pulses."
- aerovistae 9y agoDoes that mean at all times (permanently, like whenever the chip is being used) or just during manufacturing?
- jdironman 9y ago'Maintained at / in' usually means continuous or on going.I have not read the paper though, so cannot say for certain.
- marcosdumay 9y agoThat "using mostly standard silicon technology" phrase implies that cryogenic temperatures are not needed during manufacturing, only during operation.
- scentoni 9y agoIt means whenever it is being used. Manufacturing silicon chips involves temperatures from room temperature to ~1300C.
- zackmorris 9y agoNote that this is not as difficult as it sounds. Here is a video explaining how laser cooling works, by using 6 lasers pointing towards a sample with a wavelength just longer than the absorption wavelength of its atoms in order to decrease its momentum regardless of which way it's moving (details near the 2:20 mark): https://www.youtube.com/watch?v=hFkiMWrA2Bc https://www.youtube.com/watch?v=hFkiMWrA2Bc So mainstream cryogenics could be a side benefit of technologies like this. After rereading this, I'm not sure if the ESR itself can perform cooling.
- 3chelon 9y agoAbout the only ting i know about quantum computing is it will make current encryption techniques redundant. Is anyone thinking seriously about what that will mean for global e-commerce? There will be a point in time when these machines are not affordable on the mass market, but affordable by governments. At that point, presumably, we are all going to be pwned?
- volkk 9y agonot all encryption techniques-- off the top of my head, only RSA (algos that depend on prime number factorization)
- pcl 9y agoHere's a good starting point to learn more: https://en.wikipedia.org/wiki/Post-quantum_cryptography https://en.wikipedia.org/wiki/Post-quantum_cryptography Also, there's some related discussion in the amazing cinematographic masterpiece that is Sneakers: http://www.imdb.com/title/tt0105435/ http://www.imdb.com/title/tt0105435/
- deleted 9y ago[deleted]
- sebular 9y agoI think you mean "obsolete" and not "redundant" but yes, the common asymmetric encryption methods used for things like HTTPS are trivially cracked with a powerful enough quantum computer. The good news is that people have been anticipating this for a while, and there's a lot of study in the field of post-quantum encryption. From what I understand, people have come up with techniques that work (meaning nobody's discovered a reason why they wouldn't work). The bad news is that this does nothing for the data that we're currently encrypting. There's nothing to stop someone from storing today's encrypted web traffic and decoding it in the future when working quantum computers are capable. Thanks to Edward Snowden and others, we know that the US government is already hoarding and sifting through data, so I have no doubt that there are plenty of agencies planning on doing this exact thing.
- fauria 9y agoPreviously on HN, Quantum Computing Explained: https://www.clerro.com/guide/580/quantum-computing-explained https://www.clerro.com/guide/580/quantum-computing-explained
- ianopolous 9y agoThe important bit: "The UNSW team has struck a A$83 million deal between UNSW, Telstra, Commonwealth Bank and the Australian and New South Wales governments to develop, by 2022, a 10-qubit prototype silicon quantum integrated circuit – the first step in building the world’s first quantum computer in silicon." So no, they haven't built a many-qubit general quantum computer.
- vtomole 9y agoThere has been some slow but noticeable progress in building quantum computers using semiconductors. Researchers at Princeton were recently able to implement a two-qubit quantum gate in silicon [0]. [0]: https://arxiv.org/pdf/1708.03530.pdf https://arxiv.org/pdf/1708.03530.pdf
- huslage 9y agoI'm pretty sure that's not slow progress.
- vtomole 9y agoIt depends on what we mean by "slow progress". The physical implementation of a quantum computer in silicon was proposed in 1998 [0] and a two-qubit gate was recently performed on it. This is in contrast to the ion trap quantum computer, where a two-qubit gate was proposed and performed in 1995 [1]. On the other hand, superconducting quantum computers followed the same road that silicon is on right now. It took a couple of years for superconducting qubits to be robust enough to perform universal quantum computation, but it's progress has accelerated in the past couple of years. So this says nothing of how fast silicon quantum computers will progress in the future. [0]: https://en.wikipedia.org/wiki/Loss%E2%80%93DiVincenzo_quantum_computer https://en.wikipedia.org/wiki/Loss%E2%80%93DiVincenzo_quantu... [1]: https://en.wikipedia.org/wiki/Trapped_ion_quantum_computer#History_of_trapped_ion_quantum_computing https://en.wikipedia.org/wiki/Trapped_ion_quantum_computer#H...
- Evelyn65 9y ago
- naskwo 9y agoGiven the order-of-magnitude increase in speed (https://www.theregister.co.uk/2016/04/18/d_wave_demystifies_... https://www.theregister.co.uk/2016/04/18/d_wave_demystifies_...) combined with the assumption that the price of these chips will go down as commercialization becomes more viable, isn't it naive to even consider the viability of cryptocurrency? I mean, if the core underlying value of this "asset class" is the fact that there is a scarcity of numbers (like collector baseball cards) combined with ease and anonymity of transactions (like diamonds), then unlimited computing power will demolish the value of cryptocurrencies as much as alchemy would diminish the value of Au.
- tempestn 9y agoOrder of magnitude increase =/= unlimited, right? Also, it's my understanding that there is already plenty of work done on post-quantum cryptography. I don't know if it's entirely a solved problem, but my understanding is that it's at least solvable. Perhaps someone with more domain experience can weigh in.
- flignats 9y agoThere are several quantum resistant crypto currencies. I.e. IOTA
- banderman 9y agoCan you please explain what makes it quantum resistant?
- flignats 9y ago"IOTA uses hash-based signatures (https://www.imperialviolet.org/2013/07/18/hashsig.html https://www.imperialviolet.org/2013/07/18/hashsig.html) instead of elliptic curve cryptography (ECC). Not only is hash-based signatures a lot faster than ECC, but it also greatly simplifies the overall protocol (signing and verification). What actually makes IOTA quantum-secure is the fact that we use Winternitz signatures. IOTA's ternary hash function is called Curl."
- 9y ago
- philipkglass 9y agoRemarkable as they are, today’s computer chips cannot harness the quantum effects needed to solve the really important problems that quantum computers will. To solve problems that address major global challenges – like climate change or complex diseases like cancer – it’s generally accepted we will need millions of qubits working in tandem. Are there non-classical algorithms with theoretical advantages for biological or climate simulations? Or is this just more hype-nonsense courtesy of the press office?
- SolarNet 9y agoProtein folding and fluid simulations theoretically rely on these sorts of quantum calculations. I don't think any directly relevant algorithms have been developed because the hardware deosn't exist for it in the first place.
- philipkglass 9y agoGood point about protein folding. Right now it's simulated with classical physics on conventional computers; quantum chemistry algorithms on classical computers scale too poorly for use with macromolecules. But a many-qubit computer could be excellent for that and other molecular-scale calculations. (Not that getting good protein folding models would cure cancer, but it's reasonably likely to aid biological research.)
- abecedarius 9y agoAb-initio quantum chemistry calculations certainly could scale much better on quantum computers -- I skimmed a paper once, which made it sound not easy but definitely worth working on -- and that's bound to help with bioscience once they're big enough. I'm surprised at protein folding or fluid dynamics, though -- what's the general idea on how it'd help with those? Added: that is, I thought protein conformation energy was pretty well approximated with classical molecular-mechanics models, except during actual chemical reactions, and the difficulty was the sheer amount of time it takes this huge molecule to settle down to an energy minimum that's only a little below that of many alternative conformations. Is the biggest problem rather that we can't efficiently compute a consistent-enough approximation to the energy of a given conformation, so we can't distinguish the best conformation of the ones we simulated?
- IndrekR 9y agoI think it is worth to mention that their team at UNSW is hiring and has PhD scholarships available. About 30 positions are open. I am not affiliated them, but noticed the listings at http://www.cqc2t.org/employment http://www.cqc2t.org/employment
- Gatsky 9y agoThis is interesting - they plan to deliver a revolutionary device in 5 years and are about to hire 30 new people. Is that really feasible? I suppose the funding cycles mean you have no choice, because it is not possible to maintain a large dedicated research workforce for prolonged periods.
- tagrun 9y agoBefore anyone gets excited about getting a practical quantum computer soon, it should be emphasized that while they're experimentalists, this news is only about a design they have in mind to use with their SiMOS quantum dots. There's a gap between that design and the status quo of their physical quantum gates in their lab. Their gates (both single and two qubit gates) are slow and their fidelities currently are below the threshold required for surface codes. There're also big questions about the readout fidelities (which is way low at the moment) and suppressing crosstalk. That being said, quantum dots in Si/SiGE and SiMOS is a very exciting field these days.
- turndown 9y agoAre there any good introductory pieces on quantum computing? I feel like I've heard so much about the subject, yet have not found a good paper to read that outlines the essential concepts/topics involved with it.
- vtomole 9y agoThe standard text for the field is Nielsen and Chuang: https://www.amazon.com/Quantum-Computation-Information-10th-Anniversary/dp/1107002176 https://www.amazon.com/Quantum-Computation-Information-10th-...
- sharp11 9y agoMichael Nielsen also has a really nice, accessible series of intro videos: http://michaelnielsen.org/blog/quantum-computing-for-the-determined/ http://michaelnielsen.org/blog/quantum-computing-for-the-det...
- Ice_cream_suit 9y agoThe actual article ( shorn of the breathless "oh my gosh" university PR department hype ) is: Silicon CMOS architecture for a spin-based quantum computer M. Veldhorst, H. G. J. Eenink, C. H. Yang & A. S. Dzurak Nature Communications 8, Article number: 1766 (2017) doi:10.1038/s41467-017-01905-6 It can be found free at: https://www.nature.com/articles/s41467-017-01905-6 https://www.nature.com/articles/s41467-017-01905-6 ABSTRACT: "Recent advances in quantum error correction codes for fault-tolerant quantum computing and physical realizations of high-fidelity qubits in multiple platforms give promise for the construction of a quantum computer based on millions of interacting qubits. However, the classical-quantum interface remains a nascent field of exploration. Here, we propose an architecture for a silicon-based quantum computer processor based on complementary metal-oxide-semiconductor (CMOS) technology. We show how a transistor-based control circuit together with charge-storage electrodes can be used to operate a dense and scalable two-dimensional qubit system. The qubits are defined by the spin state of a single electron confined in quantum dots, coupled via exchange interactions, controlled using a microwave cavity, and measured via gate-based dispersive readout. We implement a spin qubit surface code, showing the prospects for universal quantum computation. We discuss the challenges and focus areas that need to be addressed, providing a path for large-scale quantum computing."
- maga_2020 9y agowould somebody be able to compare this design with Microsoft's topological qubit design? which one has better unwanted interference/error correction potential, also are there any foundational operations that one design could do, but the other will not be able to ?
- cyberpunk0 9y agoWhy silicon and not something like graphene