Category Archives: Quantum Computer
Elusive Majorana Particle Takes Major Step Towards Quantum Computing – IEEE Spectrum
An international team of researchers has fashioned a device from nanowires that may finally prove the existence oflong-theorized quasiparticles known asMajorana particles. Once these Majorana particles are identified and isolated, they could form the basis of a quantum bitor qubitthat would process information in a new kind of quantum computer with improvedstability.
Ever since 1937, when the Italian physicist Ettore Majorana first theorized the existence of the quasiparticle that takes his name, there has been much effort to prove that it really exists, withlittle to show for it. But this changed back in 2012, when researchers at Delft University of Technology (TU Delft)in the Netherlandssaw strong hints of Majoranas when they sent electrons into a semiconducting nanowire placed alongside superconducting material.
Since that 2012 Delft research, there have been a number of experiments that have reported evidence of Majoranas in a similar system. However, all of those experiments, including the original one at Delft, left open the possibility of alternative explanations for the results. So, unilnow, there has been no smoking-gun evidence of Majoranas, saidHao Zhang, a post-doc at TU Delft, in an e-mail interview with IEEE Spectrum.
There remained one definitive way to prove the existence of these Majorana particles and that was for them to exchange places along the nanowire, a phenomenon referred to as exchanging statistics of the particles. These statistics describe how the quantum mechanics of the system changewhen two indistinguishable particles switch places.
This exchange of places along the nanowire is also called braiding. These braids form the logic gates of topological quantum computers. However, no one could see how this braiding was possible because the act of getting the particles to pass each other in this nanowire would annihilate them.
If this braiding of these quasiparticles could somehow be artificially induced, researchers theorized,it would result in a far more stable method for quantum computing than employing trapped quantum particles. Thats because the systemwouldnt be susceptible to outside influences like thermal fluctuations.
In research described in the journal Nature, the researchers, from TU Delft, Eindhoven University of Technology in the Netherlands, and the University of California,Santa Barbara, created a hashtag-like device made from nanowires. It provided a four-way intersection in which two Majorana particles could exchange places in the nanowire-based structure without coming in contact with each other and annihilating each other.
These braiding experiments can give experimental results, which are unique to Majoranas, and cannot be mimicked by other alternative scenarios, says Zhang. Thus it can be treated as the smoking-gun evidence.
Braiding not only provides definitive evidence of Majoranas, but perhaps more importantly, it also proves the feasibility of topological quantum computing in which the fundamental assumption of their operation is based on the braiding phenomenon. In other words, the braiding not only proves the existence of Majoranas, but also provides the mechanism by which they could serve as the basis of a qubit for a topological quantum computer.
This means that the quantum information (qubit) can be stored and manipulated simply by braiding (swapping) of Majoranas. This process of braiding is supposed to be robust against error since the outcome only depends on the order of braiding operations, adds Zhang.
In the video below, you can see a description of how the Majoranas are formed from the combining of semiconductor nanowires with a superconductor material, and how once formed can be manipulated into serving as qubits in a topological quantum computer.
This robustness against error depends on Majornas ability to maintain superposition. In previous quantum computing proposals, the unpaired electrons of certain ions can assume either of two spin states, up or downor in terms of digital logic, 0 or 1. When these ions are hit with a microwave pulse, the unpaired electron can take on both the 0 and 1 state simultaneously. These two states constitute what is termed superposition.
Unil now, it has only been possible to maintain a superposition state for very short periods of time because the spin states of neighboring atoms quickly destroy the coherent state.This makesthe life of the qubit too short for it to perform the desired number of quantum computations.
This is the biggest advantage of Majorana qubit compared to other qubits, says Zhang. The Majorana qubit should have longer coherence time (robust against error) due to its topological protection.
Zhang says that they are already working on the engineering of a qubit based on these Majoranas that will involve the fabrication of a microwave pulse circuit.
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Elusive Majorana Particle Takes Major Step Towards Quantum Computing - IEEE Spectrum
Australia gets quantum computing company – ACS (registration)
The new Silicon Quantum Computing leadership team. Source: cqc2t.org
The NSW Government has teamed up with the University of New South Wales (UNSW) in a bid to create the worlds first quantum computer.
The governments $8.7 million investment comes as one of the first expenditures from its recently announced $26 million Quantum Computing Fund.
The funding will support a new company, Silicon Quantum Computing Pty Ltd, responsible for retaining intellectual property in Australia, supporting new industries based around quantum computing, and most importantly, creating the worlds first quantum computer.
Deputy Premier and Minister for Skills, John Barilaro, spoke about the new partnership.
NSW has an incredible and an unusual depth of talent in quantum research, and the world is watching our progress.
This new company, led by UNSW, will help to ensure we remain global leaders in the race to develop a silicon-based quantum computer.
Professor Michelle Simmons and her incredibly talented team of researchers at UNSW have put Australia ahead of the pack in the race to build the worlds first fully-functional quantum computer in silicon, he said.
The company will operate within the Centre of Excellence for Quantum Computation and Communication Technology (CQC2T), residing in the UNSW School of Physics.
CQC2T labs were opened by Prime Minister Malcolm Turnbull in April 2016, where it was announced they would accelerate Australia in the international race to build the worlds first quantum computer in silicon.
Also backed by Commonwealth Bank, Telstra and the Federal government, CQC2T believes it is on track to create an operational quantum system within 10 to 15 years.
The new company is expected to create an extra 40 jobs, including 25 post-doctoral researchers and 12 PhD students.
Quantum computing can perform complex equations that would otherwise take years to complete in just minutes, using quantum bits (qubits).
While IBM has already created a 16 and 17-qubit computer, CQC2T is hoping to process a world-first 30-qubit system, capable of outperforming a classical computer.
Minister for Industry, Innovation and Science the Hon Arthur Sinodinos spoke of the importance of quantum computing for Australia.
Quantum computers are expected to transform the way we live, work, and do business over the coming decades, creating new jobs in new industries not even imaginable today, he said.
If Australia wins the global race to build a functional quantum computer, it will create new industries and job opportunities across our economy.
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Australia gets quantum computing company - ACS (registration)
Russians Lead the Quantum Computer Race With 51-Qubit Machine – Edgy Labs (blog)
An international research team successfully created and tested a record-breaking quantum supercomputer. Running on 51 qubits, the new machine surpasses the theoretical threshold of quantum supremacy.
Like Schrdingers cat, qubits, or quantum bits, are undecided and can be in two positions simultaneously. In other words, if traditional computers have bits that can take the value of 1 or 0 at a time, qubits can be either at the same time.
Hence the edge quantum computing has over classical computing in solving very complex calculations much faster.
Qubits allow the development of new computational algorithms, which are much more productive than silicon-based iterations.
The more qubits a quantum computer uses, the more processing power it has.
But most advanced quantum computational systems available today are still far behind supercomputers in terms of their practical applicationsalthough the situation is changing very fast indeed.
Theres a theoretical threshold after which quantum computers would surpass most powerful classical supercomputers. Scientists believe it should happen somewhere around 50 qubits.
Currently, the most advanced quantum chips are below 20 qubits, such as theIBM Q that uses 17 qubits.
Google also is no stranger to the quantum race, as its working on a 49-qubit 14-meter machine using superconducting circuits.
Googles 49 qubit computer was supposed to be the highlight of the ICQT 2017 (The International Conference on Quantum Technologies, held July 12th16th in Moscow).
Designed by John Martinis, a professor at University of California at Santa Barbara, Googles computer will use a chip embedded with 49 qubits (0.6 cm by 0.6 cm).
But as groundbreaking Googles machine might be, it was another machine that stole the show.
During the same day of the ICQT 2017 that Martinis was supposed to give a lecture about his quantum device, Mikhail Lukin, the co-founder of RQC, made his own announcement.
Mikhails team, including Russian and American scientists, have built the worlds most powerful functional quantum computing system, running on 51 qubits.
The new quantum system uses an array of 51 cold atoms in lieu of qubits. Locked up on laser cells, these atoms should be kept at extremely low temperatures.
we observe a novel type of robust many-body dynamics corresponding to persistent oscillations of crystalline order after a sudden quantum quench, said researchers in a paper available at arXiv.org. These observations enable new approaches for exploring many-body phenomena and open the door for realizations of novel quantum algorithms.
The model was successfully tested in the labs of Harvard University, solving physics problems that silicon chip-based supercomputers would have a hard time replicating.
Originally posted here:
Russians Lead the Quantum Computer Race With 51-Qubit Machine - Edgy Labs (blog)
Quantum Computing and Financial Trading – LeapRate
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If you have not heard of quantum computing, you are not alone.
To date, most of the work of quantum computing has been taking place in universities, where super smart tech geeks work with never-before-seen technology to change the world using algorithms that most of us cant comprehend.
If youre not a tech head or theoretical mathematician, defining quantum computing doesnt really give you an understanding of what it means and what it is likely to be able to achieve. But lets give it a go anyhow.
The difference between current computing and quantum computing is the difference between binary bits of technology, where each bit is either a binary 0 or 1, and quantum computers qubits, which can be zero, one or a quantum superposition of the qubit states. In my head, I guess it is like the difference between 2D and 3D movies, but thats just an educated assumption.
What does this mean practically?
At its basic level, quantum computers are able to figure out many of the encryptions that are not possible to the figure out on a normal computer, because of the limitations of the binary bits in traditional computing. This is just one of the practical advances, but the current level of cryptographic encryptions would not be effective defense against quantum computing, leading many in the security community to fear a cryptopocalypse (which is a pretty cool way of mixing cryptography and apocalypse, even if it is a totally scary concept).
For the financial industry, it has certain impacts. The first is obviously the need to create a more secure situation to protect money, since the current encryptions will be useless in the face of quantum computing.
The second interesting one is its potential to seriously disrupt the financial markets. Quantum computers are able to execute more complex algorithms than todays computers and execute them more quickly. It can solve issues in algorithmic trading in a way that is unfeasible by current standards of computing. This means that the capabilities of algorithmic trading will increase significantly with the advent of quantum computing. By changing the capabilities of certain types of trading, the market metrics will also change, making it a significant disruptor.
Not only are existing algorithms able to be more effectively computed, but a significant potential exists to develop new algorithms. Each development will represent a new, greater level of computational capabilities, potentially rendering the previous algorithm obsolete. Companies will focus on creating new algorithms for both profit and competitive advantage.
Quantum computing has the chance to impact security in the financial industry and develop algorithmic trading, disrupting existing market dynamics and creating a new dynamic in the process. This brave, new world of computing capabilities has the power to create new unique disruptions in a similar way to AI and machine learning. Quantum computing can harness data and create algorithms to solve problems in ways that we cannot yet fathom, and like each iteration of technology that came before it, quantum computing will have the power to change the world.
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Quantum Computing and Financial Trading - LeapRate
Bitcoin vs. The NSAs Quantum Computer Bitcoin Not Bombs
Yesterday we learned from new Snowden leaks that the NSA is working to build a quantum computer. The Washington Post broke the story with the rather sensationalist headline, NSA seeks to build quantum computer that could crack most types of encryption.
Naturally, this raised much concern among the new Bitcoiners on Reddit and Facebook. The reality, however, is there wasnt much disclosed that people didnt already know or expect. Weve known that the NSA has openly sponsored quantum computing projects in the past. The fact that it has an in-house project called Penetrating Hard Targetsis new, but not really unexpected. We learned this project has a $79.7 million budget, but quite frankly that isnt that much. And as The Post notes, the documents dont reveal how far along they are in their research andIt seems improbable that the NSA could be that far ahead of theopen world without anybody knowing it.
Nevertheless, this seems like a good time to discuss the implications of quantum computing with respect to the future of Bitcoin.
Lets start with a little primer for those who are unfamiliar with quantum computing.Todays computers encode information into bits binary digits, either 0 or 1. These bits are usually stored on your computers hard disk by changing the polarity of magnetization on a tiny section of a magnetic disk, or stored in RAM or flash memory represented by two different levels of charge in a capacitor. Strings of bits can be combined to produce data that is readable by humans. For example, 01000001 represents the letter A in theextended ASCII table. Any calculations that need to be performed with the bits are done one at a time.
Quantum computers, on the other hand, use the various states of quantum particles to represent quantum bits (qubits). For example, a photon spinning vertically could represent a 1, while a photon spinning horizontally could represent a 0. But photons can also exist in a rather weird state called superposition. That is,while they can spin vertically, horizontally, and diagonally, they can also spin in all those directionsat the same time. Dont ask me how thats possible, its the bizarro world of quantum mechanics.
What this means for practical purposes is while a traditional computer can perform only one calculation at a time, a quantum computer could theoretically perform millions of calculations all at once, improving computing performance by leaps and bounds.
Now when journalists write things like, In room-size metal boxes secure against electromagnetic leaks, the National Security Agency is racing to build a computer that could break nearly every kind of encryption used to protect banking, medical, business and government records around the world, it naturally makes people think its the end of cryptography as we know it. But that isnt the case.
Lets consider the type attack most people think of when hear of quantum computersa brute force attack. This is where you just keep checking different keys until you eventually find the right one. Given enough time, you could brute force any encryption key. The problem is it would take billions or trillions of years for a modern computer to brute force a long encryption key. But surely quantum computers could do this right? This is from Bruce Schneiers 1996 book, Applied Cryptography:
One of the consequences of the second law of thermodynamics is that a certain amount of energy is necessary to represent information. To record a single bit by changing the state of a system requires an amount of energy no less than kT, where T is the absolute temperature of the system and k is the Boltzman constant. (Stick with me; the physics lesson is almost over.)
Given that k = 1.3810-16erg/Kelvin, and that the ambient temperature of the universe is 3.2Kelvin, an ideal computer running at 3.2K would consume 4.410-16ergs every time it set or cleared a bit. To run a computer any colder than the cosmic background radiation would require extra energy to run a heat pump.
Now, the annual energy output of our sun is about 1.211041ergs. This is enough to power about 2.71056single bit changes on our ideal computer; enough state changes to put a 187-bit counter through all its values. If we built a Dyson sphere around the sun and captured all its energy for 32 years, without any loss, we could power a computer to count up to 2192. Of course, it wouldnt have the energy left over to perform any useful calculations with this counter.
But thats just one star, and a measly one at that. A typical supernova releases something like 1051ergs. (About a hundred times as much energy would be released in the form of neutrinos, but let them go for now.) If all of this energy could be channeled into a single orgy of computation, a 219-bit counter could be cycled through all of its states.
These numbers have nothing to do with the technology of the devices; they are the maximums that thermodynamics will allow. And they strongly imply that brute-force attacks against 256-bit keys will beunfeasibleuntilcomputers are built from something other than matter and occupy something other than space.
To recap, if you could harness all the energy from a supernova and channel it into an ideal computer, you still couldnt brute force a typical encryption key. Needless to say, if you are going to break commercial encryption algorithms youre going to have to attack the underlying math.
Today, most public-key encryption algorithms rely on either the difficulty of integer factorization (RSA) or the difficulty of discrete logarithm problems (DSA/El Gamal, and Elliptic Curve Cryptography).In 1994, mathematician Peter Shor demonstrated an efficient quantum algorithm for factoring and calculating discrete logarithms that would break public-key encryption when used with a quantum computer. This wouldnt break all types of cryptography, however. Traditional symmetric-key cryptography and cryptographic hash functions would still be well out of range of quantum search algorithms.
Impact on Bitcoin
Bitcoin uses several cryptographic algorithmsThe Elliptic Curve Digital Signature Algorithm (ECDSA) for signing transactions and the hash functions SHA-256 and RIPEMD160. If the NSA succeeds in developing a cryptologically useful quantum computer, ECDSA would fall while SHA-256 and RIPEMD160 would remain secure.
The good news is that ECDSA should be relatively easy to swap out if/when it becomes compromised. It would be much worse if SHA-256 were to go down. If youre not in tune to the mechanics of Bitcoin, SHA-256 is used in Bitcoin mining. At the moment, billions of dollars have been spent on custom computer chips that do nothing but perform SHA-256 calculations. If SHA-256 were to go down, those custom chips would turn into expensive paperweights. If that happened suddenly (as opposed to allowing for a smooth transition to another hash function), it would be pretty catastrophic. The security in bitcoin relies on the fact that it would be too difficult and expensive for an attacker to command 51% of the processing power in the network. A sudden switch to another hash function would significantly compromise security and likely cause the price to tank. But as I mentioned, Bitcoiners can rest easy because SHA-256 isnt threatened by quantum computers (although that doesnt mean someone wont find a feasible attack in the future).
Back to ECDSA. This algorithm generates a public/private key pair. In Bitcoin, you keep the private key secret and use it sign your transactions, proving to the network that you own the bitcoins associated with a particular bitcoin address. The network verifies your signature by using the corresponding public key. A functioning quantum computer would allow the NSA to derive anyones private key from their public key. So do this mean that the NSA would be able to steal everyones bitcoins? Not exactly.
Heres the thing, in Bitcoin your public key isnt (initially) made public. While you share your Bitcoin address with others so that they can send you bitcoins, your Bitcoin address is only a hash of your public key, not the public key itself. What does that mean in English? A hash function is a one-way cryptographic function that takes an input and turns it into a cryptographic output. By one-way I mean that you cant derive the input from the output. Its kind of like encrypting something then losing the key. To demonstrate, lets calculate the RIPEMD160 hash of Hello World.
A Bitcoin address is calculated by running your public key through several hash functions as follows:
All of that is a complicated way of saying that while an attacker with a quantum computer could derive the private key from the public key, he couldnt derive the public key from the Bitcoin address since the public key was run through multiple quantum-resistant one-way hash functions.
However, you do have to broadcast your public key to the network to make a transaction, otherwise there is no way to verify your signature. What this implies is that in the face of an NSA quantum computer all Bitcoin addresses would have to be considered one-time use addresses. Whenever you make a transaction you would have to send any excess bitcoin to a newly generated address as change. If you didnt remove the entire balance from your address, the NSA could steal the remainder.While this is inconvenient, it would buy the developers enough time to swap out ECDSA for a quantum-resistant digital signature scheme.
Post-Quantum Digital Signatures
This section is going to be a little technical but hopefully not too difficult for beginners to follow. There are several different types of post-quantum public-key encryption systems: lattice-based, code-based, multivariate-quadratic, and hash-based. As I already mentioned, cryptographic hash functions are presumed to be quantum-resistant. Given that, it should be possible to build a replacement digital signature scheme for ECDSA using only hash functions. Lets take a look at these hash-based systems since they are easy to understand and the hash functions theyre based on are already widely used.
Lamport One-Time Signature Scheme (LOTSS)
To begin, were going to want to use a hash function with at least a 160-bit output to provide adequate security. RIPEMD160 or SHA-1 should work. To generate the public/private key pair, well start by generating 160 pairs of random numbers (320 numbers total). This set of random numbers will serve as the private key.
To generate the public key well take the RIPEMD160 hash of each of the 320 random numbers. (Note: Im going to have to cut the numbers in half to fit them in this table)
Now to sign a message with a Lamport signature well first create a message digest by hashing the message with RIPEMD160 (in Bitcoin we would hash the transaction) then converting the output to binary. Well once again use Hello World as an example.
Next, well match up each binary digit with each pair in our private key. If the bit is 0 we will add the first number in the pair to our signature, if it is 1 well add the second.
Finally to verify the signature is valid, youll first create a message digest using the same process as above. Then hash each of the 160 numbers in the signature with RIPEMD160. Finally, check to make sure these hashes match the hashes in the public key that correspond with the message digest.
So there you have it, a quantum-resistant digital signature scheme using only hash functions. Only the person in possession of the 320 random numbers in the private key could have generated a signature that hashes to the public key when compared to the digest. However, while his scheme does in fact work, it isnt without problems. First, as the name suggests, LOTSS signatures can only be used once. The reason for this is because you are essentially releasing half of your private key with each signature. If you were to sign multiple messages, your private key would be completely compromised. If this were used in Bitcoin, you still could only use each Bitcoin address once.
Equally problematic, the key sizes and signatures are ridiculously large. The private and public keys are 6,400 bytes compared to 32 and 64 for the ECDSA private and public keys. And the signature is 3,200 bytes compared to 71-73 bytes. Bitcoin already has issues with scalability, increasing the key and signature sizes by that much would make the problems much worse.
The Lamport private key can be dramatically reduced in size by generating the random numbers from a single random seed. To do this you would just take RIPEMD160(seed + n) where n starts at 1 and gets incremented to 320. Unfortunately, the size of the private key isnt so much the problem as is the size of the public key and signature. There is another one-time signature scheme called Winternitz signatures that has the potential to reduce key size but at the cost of hash operations. Fortunately, we arent done yet.
Merkle-Signature Scheme (MSS)
The Merkle Signature Scheme combines the one-time signature scheme (either Lamport or Winternitz) with a Merkle tree (also called a hash tree). This allows us to use one public key to sign many messages without worrying about compromising security. Lets see how this works.
Well start by generating a number of Lamport key pairs. The number well generate will be equal to the number of signatures we want to get out of a single public key. Lets just say eight as an example. Next well calculate a Merkle tree using each of the eight Lamport public keys. To do this, the public keys are paired together, hashed, then the hashes are concatenated together and hashed again. This process is repeated until something looking like an NCAA Tournament bracket is formed.
The hash at the very top of the tree (the Merkle root) is the Merkle public key. This massively reduces the public key size from 6,400 bytes in the Lamport signature to only 20 bytes, the length of a single RIPEMD160 hash.
To calculate a signature, you select one of your Lamport key pairs and sign the message digest just like before. This time, the signature will be the Lamport signature plus each one of leafs in the Merkle tree leading from the public key to the root.
In the above diagram the signature would be:
To verify the Merkle signature one would just verify the Lamport signature, then check to make sure the leafs hash to the Merkle public key. If so, the signature is valid.
There are several advantages of the MSS over LOTSS. First, the public and private keys are reduced to 20 bytes from 6,400 bytes. Also, you can create multiple signatures per public key. But there is still a major draw back. The more messages you want to sign with your public key, the larger the Merkle tree needs to be. The larger the tree, the larger the signature. Eventually the signature starts to become impractically large, especially for use in Bitcoin. This leads us to the final post-quantum signature schemes well discuss.
CMSS And GMSS
MSS has been known for over 30 years and has remained essentially unscathed despite extensive cryptanalysis. However, most of the improvements to it have come in the last five years or so. In my brief survey of the literature, it seems a couple signature schemes by Buchmann, Dahmen, Klintsevich, et. al., are the most promising of the lot. These are the Improve Merkle Signature Scheme (CMSS) and Generalized Merkle Signature Scheme (GMSS) (Links to the academic papers can be found here and here). Two of the cryptographers behind this signature scheme are authors of a textbook on post-quantum cryptography.
Both CMSS and GMSS offer substantially improved signature capacity with reasonable signature lengths and verification times. GMSS in particular offers virtually unlimited signature capacity at 280 signatures but with slower performance in others areas compared to CMSS. They accomplishes this by breaking the system up into separate Merkle trees of 2n leafs. A signature from the root tree is used to sign the public key of the tree below it which signs the tree below it and so on.
So it seems to me that either of these signature schemes would be a serious candidate to replace Bitcoins ECDSA in a post-quantum world. But why not just go ahead and implement it now and rather than wait until the NSA springs a surprise on us? Lets do a little comparison and take a look at the time (t) and memory (m) requirements for each. CMSS variants have signature capacities of 220, 230, and 240 while GMSS has signature capacities of 240 and 280. I would assume that 240 if not 230 would be plenty for Bitcoin as I cant imagine someone would make more than a billion or trillion transactions from a single address. Also, GMSS can be optimized for faster verification times but at the expense of a 25% larger signature.
So from the table we can see that CMSS and GMSS actually perform better than ECDSA in public key size and signature time. However, in the critical variable that will affect scalability, signature size, they dont perform nearly as well. Verification time for CMSS is actually better than ECDSA which would actually improve scalability and the optimized variant of GMSS is relatively close, but signature size for both would definitely be an issue. Consider some very rough estimates: the average transactions size is currently about 500 bytes, either CMSS or GMSS would push it up over 4000 bytes. That means you could be looking at an increase in the size of the block chain of upwards of 700%. The block chain is currently at 12.7 gigabytes. Had Bitcoin employed either of these signature schemes from the beginning, it would be over 100 gigabytes right now. Signature and key size isnt a problem that is unique to hash-based signature schemes either, most of the others are in the same ballpark.
Also, note the insane keygen time for GMSS. If you left your computer running for 24 straight hours you would have only generated 3 bitcoin address and thats using the optimized variant with larger signatures! I suspect, however, that an ASIC hardware wallet would significantly improve that performance. Keygen for CMSS isnt that bad.
So in other words, Bitcoin cant adopt one of these signature schemes at the moment if we want to scale beyond present capacity. However, by the time quantum computers become viable, Moores law will likely have brought the cost of storage and processing power down to the point where CMSS, GMSS or one of the other types of post-quantum signature schemes could easily be merged into Bitcoin. Until then, lets not lose any sleep over Penetrating Hard Targets.
Original content by Chris, copyleft, tips welcome
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Excerpt from:
Bitcoin vs. The NSAs Quantum Computer Bitcoin Not Bombs
qBitcoin: A Way of Making Bitcoin Quantum-Computer Proof? – IEEE Spectrum
A new quantum cryptography-based Bitcoin standard has been proposed that could harden the popular cryptocurrency against the advent of full-fledged quantum computers. Bitcoin as it now exists involves traditional public key cryptography and thus could conceivably be hacked by a future quantum computer strong enough to break it. However, quantum cryptography, which is based not on difficult math problems but the fundamental laws of physics, is expected to be strong enough to withstand even quantum computer-powered attacks.
The proposal, dubbed qBitcoin, posits transmission of quantum cryptographic keys between a remitter and a receiver of the eponomous named cryptocurrency, qBitcoin. The system would use provably secure protocols such as theBB84quantum key distribution scheme.
To exchange qBitcoin, then, requires that there be a transmission network in place that can send and receive bits of quantum information, qubits. And that is no mean feat, considering it typically involves preserving the polarization states of individual photons across thousands of kilometers. To date, there are five knownquantum key distributionnetworks in the United States, Switzerland, Austria, and Japan. China is working ontheir ownmassive 2000-km link, as well. And a number of satellite-to-satellite and satellite-to-ground quantum key distribution networks are alsobeingdevelopedandprototyped.
Which is to say that qBitcoin or something like it could not be scaled up today. But if the quantum computer singularity is approaching, in which a powerful enough machinecould threaten existing cryptography standards, quantum cryptography would be an essential ingredient of the post-Y2Q age. So existing quantum key distribution networks might at least serve as outposts in a burgeoning global quantum network, like Western Union stations in the early days of the telegraph.
Some things about qBitcoin might appear the same to any Bitcoin user today. Bitcoin is a peer to peer system, and qBitcoin is also peer to peer, says Kazuki Ikeda, qBitcoins creator and PhD student in physics at Osaka University in Japan.Hesays compared to Bitcoin, qBitcoin would offer comparable or perhaps enhanced levels of privacy, anonymity, and security. (That said, his paper that makes this claim is still under peer review.)
However, the lucrative profession ofBitcoin mining, under Ikedas protocol, would be very different than what it is today. Transactions would still need to be verified and secured. Butinstead of todays system of acryptographic puzzles, qBitcoins security would rely on a 2001proposalfor creating aquantum digital signature.Such a signature would rely on the laws of quantum physics to secure the qBitcoin ledger from tampering or hacking.
Ikeda's proposal is certainly not the first to suggest a quantum-cryptographic improvement onclassical-cryptography-based digital currencies. Other proposals in2010,2016,and evenearlier this yearhave also offered up variations on the theme. All work to mitigate against the danger large-scale quantum computers would represent to Bitcoin.
Of course, not every solution to the quantum singularity is as promising as every other. A person going by the handle amluto criticized Ikedas qBitcoin proposal onaprominent message boardlast week. (amluto claimed to be author of one of aprevious quantum currency proposalsfrom 2010presumably the 2010 proposals co-author Andrew Lutomirski, althoughIEEE Spectrumwas unable to confirm this supposition at press time.)
This is nonsense It's like saying that you can transmit a file by mailing a USB stick, which absolutely guarantees that you, the sender, no longer have the original file. That's wrongall that mailing a USB stick guarantees is that you don't have the USB stick any more, not that you didn't keep a copy of the contents. Similarly, quantum teleportation eats the input state but says nothing about any other copies of the input state that may exist.
Ikeda says he disagrees with the analogy. The point, he says, is that there are no other copies of the input state as it's called abovein other words of the quantum keys that secure qBitcoin. So, Ikeda says, qBitcoin is safe just like Bitcoin is safe today.
But one day, thanks to quantum computers, Bitcoin, will no longer be safe. Someone will needto save it. And, no matter who devises the winning protocol, the thing that threatens Bitcoinmay in fact also be the thing that comes to its rescue: The cagey qubit.
Read more:
qBitcoin: A Way of Making Bitcoin Quantum-Computer Proof? - IEEE Spectrum
Hype and cash are muddying public understanding of quantum … – Phys.Org
An ion trap used for quantum computing research in the Quantum Control Laboratory at the University of Sydney. Michael Biercuk, Author provided Special piping and wiring supports quantum research in the Sydney Nanoscience Hub. Credit: AINST, Author provided
It's no surprise that quantum computing has become a media obsession. A functional and useful quantum computer would represent one of the century's most profound technical achievements.
For researchers like me, the excitement is welcome, but some claims appearing in popular outlets can be baffling.
A recent infusion of cash and attention from the tech giants has woken the interest of analysts, who are now eager to proclaim a breakthrough moment in the development of this extraordinary technology.
Quantum computing is described as "just around the corner", simply awaiting the engineering prowess and entrepreneurial spirit of the tech sector to realise its full potential.
What's the truth? Are we really just a few years away from having quantum computers that can break all online security systems? Now that the technology giants are engaged, do we sit back and wait for them to deliver? Is it now all "just engineering"?
Why do we care so much about quantum computing?
Quantum computers are machines that use the rules of quantum physics in other words, the physics of very small things to encode and process information in new ways.
They exploit the unusual physics we find on these tiny scales, physics that defies our daily experience, in order to solve problems that are exceptionally challenging for "classical" computers. Don't just think of quantum computers as faster versions of today's computers think of them as computers that function in a totally new way. The two are as different as an abacus and a PC.
They can (in principle) solve hard, high-impact questions in fields such as codebreaking, search, chemistry and physics.
Chief among these is "factoring": finding the two prime numbers, divisible only by one and themselves, which when multiplied together reach a target number. For instance, the prime factors of 15 are 3 and 5.
As simple as it looks, when the number to be factored becomes large, say 1,000 digits long, the problem is effectively impossible for a classical computer. The fact that this problem is so hard for any conventional computer is how we secure most internet communications, such as through public-key encryption.
Some quantum computers are known to perform factoring exponentially faster than any classical supercomputer. But competing with a supercomputer will still require a pretty sizeable quantum computer.
Money changes everything
Quantum computing began as a unique discipline in the late 1990s when the US government, aware of the newly discovered potential of these machines for codebreaking, began investing in university research
The field drew together teams from all over the world, including Australia, where we now have two Centres of Excellence in quantum technology (the author is part of of the Centre of Excellence for Engineered Quantum Systems).
But the academic focus is now shifting, in part, to industry.
IBM has long had a basic research program in the field. It was recently joined by Google, who invested in a University of California team, and Microsoft, which has partnered with academics globally, including the University of Sydney.
Seemingly smelling blood in the water, Silicon Valley venture capitalists also recently began investing in new startups working to build quantum computers.
The media has mistakenly seen the entry of commercial players as the genesis of recent technological acceleration, rather than a response to these advances.
So now we find a variety of competing claims about the state of the art in the field, where the field is going, and who will get to the end goal a large-scale quantum computer first.
The state of the art in the strangest of technologies
Conventional computer microprocessors can have more than one billion fundamental logic elements, known as transistors. In quantum systems, the fundamental quantum logic units are known as qubits, and for now, they mostly number in the range of a dozen.
Such devices are exceptionally exciting to researchers and represent huge progress, but they are little more than toys from a practical perspective. They are not near what's required for factoring or any other application they're too small and suffer too many errors, despite what the frantic headlines may promise.
For instance, it's not even easy to answer the question of which system has the best qubits right now.
Consider the two dominant technologies. Teams using trapped ions have qubits that are resistant to errors, but relatively slow. Teams using superconducting qubits (including IBM and Google) have relatively error-prone qubits that are much faster, and may be easier to replicate in the near term.
Which is better? There's no straightforward answer. A quantum computer with many qubits that suffer from lots of errors is not necessarily more useful than a very small machine with very stable qubits.
Because quantum computers can also take different forms (general purpose versus tailored to one application), we can't even reach agreement on which system currently has the greatest set of capabilities.
Similarly, there's now seemingly endless competition over simplified metrics such as the number of qubits. Five, 16, soon 49! The question of whether a quantum computer is useful is defined by much more than this.
Where to from here?
There's been a media focus lately on achieving "quantum supremacy". This is the point where a quantum computer outperforms its best classical counterpart, and reaching this would absolutely mark an important conceptual advance in quantum computing.
But don't confuse "quantum supremacy" with "utility".
Some quantum computer researchers are seeking to devise slightly arcane problems that might allow quantum supremacy to be reached with, say, 50-100 qubits numbers reachable within the next several years.
Achieving quantum supremacy does not mean either that those machines will be useful, or that the path to large-scale machines will become clear.
Moreover, we still need to figure out how to deal with errors. Classical computers rarely suffer hardware faults the "blue screen of death" generally comes from software bugs, rather than hardware failures. The likelihood of hardware failure is usually less than something like one in a billion-quadrillion, or 10-24 in scientific notation.
The best quantum computer hardware, on the other hand, typically achieves only about one in 10,000, or 10-4. That's 20 orders of magnitude worse.
Is it all just engineering?
We're seeing a slow creep up in the number of qubits in the most advanced systems, and clever scientists are thinking about problems that might be usefully addressed with small quantum computers containing just a few hundred qubits.
But we still face many fundamental questions about how to build, operate or even validate the performance of the large-scale systems we sometimes hear are just around the corner.
As an example, if we built a fully "error-corrected" quantum computer at the scale of the millions of qubits required for useful factoring, as far as we can tell, it would represent a totally new state of matter. That's pretty fundamental.
At this stage, there's no clear path to the millions of error-corrected qubits we believe are required to build a useful factoring machine. Current global efforts (in which this author is a participant) are seeking to build just one error-corrected qubit to be delivered about five years from now.
At the end of the day, none of the teams mentioned above are likely to build a useful quantum computer in 2017 or 2018. But that shouldn't cause concern when there are so many exciting questions to answer along the way.
Explore further: Developing quantum algorithms for optimization problems
This article was originally published on The Conversation. Read the original article.
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Hype and cash are muddying public understanding of quantum ... - Phys.Org
Silicon Quantum Computing launched to commercialise UNSW … – ZDNet
A new company dubbed Silicon Quantum Computing (SQC) has been launched to take advantage of and commercialise the work done by the University of New South Wales (UNSW) in the quantum space.
SQC will work out of new laboratories within the Centre for Quantum Computation and Communication Technology (CQC2T) at UNSW, and is slated to hire 40 staff members -- made up in part by 25 post-doctoral researchers and 12 PhD students.
The board for SQC will consist of professor Michelle Simmons, who has been the driving force behind CQC2T; Telstra chief scientist Hugh Bradlow; Commonwealth Bank of Australia (CBA) CIO David Whiteing; and Secretary of the federal Department of Industry, Innovation and Science Glenys Beauchamp, with corporate lawyer Stephen Menzies to serve as its interim chair.
Announced on Wednesday as a new shareholder, but not taking a board seat, was the NSW government, which funded the company to the tune of AU$8.7 million from its Quantum Computing Fund.
The state government funding follows CBA investing AU$14 million, Telstra injecting AU$10 million, the federal government allocating AU$25 million over four years, and UNSW putting $25 million towards CQC2T.
SQC is targeting having a 10-qubit machine commercialised by 2022.
Menzies told ZDNet that the creation of the company would shorten the time to market by three years, and allow for a patent portfolio to be built. He said the company is seeking three more investors to fund it at similar levels to Telstra and CBA, and is currently on the hunt for a CEO.
"We will fund hardware, but from that we will develop a patent pool which we hope will be without peer in the world," Menzies said during the launch.
"In the first five years, we are very focused, the business plan is focused on the patents associated with an engineered 10-qubit device. But beyond that, we see that we have a stage on which we develop across Australia and across Australian institutions, a broad quantum industry."
Minister for Industry, Innovation and Science Arthur Sinodinos said quantum computing was important to the country's future.
"Whatever sector of innovation, we want to be really good in, we need to be world beaters," he said on Wednesday.
"We want to be able to create a competitive advantage, command a premium, and you do that by doing something new, something that others find it hard to replicate, or it takes them time to replicate and by the time they have replicated it, you've moved on to something else."
Previously, Simmons said she believes the work completed by CQC2T to develop silicon-based qubits will win out in the race to a 30-qubit system.
"We do believe that silicon is the one that has longevity; it's a manufacturable material, and it has some of the highest-quality qubits that are out there," Simmons said in June.
"That's why it's very exciting for Australia. We actually believe this can go all the way, and we believe we can build it in Australia."
Telstra chief scientist Bradlow reiterated on Wednesday that Telstra sees itself offering quantum computing as a service.
"I can assure you they are not going to walk in on day one and know how to use these things," he said previously.
"We want to be able to offer it as-a-service to them ... they will need a lot of hand holding, and they are not going to run the equipment themselves, it's complicated."
For its part, CBA is preparing for a quantum future by using a quantum computing simulator from QxBranch.
"The difference between the emulator of a quantum computer and the real hardware is that we run the simulator on classical computers, so we don't get the benefit of the speed up that you get from quantum, but we can simulate its behaviour and some of the broad characteristics of what the eventual hardware will do," QxBranch CEO Michael Brett told ZDNet in April.
"What we provide is the ability for people to explore and validate the applications of quantum computing so that as soon as the hardware is ready, they'll be able to apply those applications and get the benefit immediately of the unique advantages of quantum computing."
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Silicon Quantum Computing launched to commercialise UNSW ... - ZDNet
Introducing Australia’s first quantum computing hardware company – CIO Australia
Australia's first quantum computing hardware company launched today, with the goal of producing a 10 qubit integrated circuit prototype by 2022.
Silicon Quantum Computing (SQC) Pty Ltd will develop and commercialise a prototype circuit, which will serve as a "forerunner to a silicon-based quantum computer" the company said.
The company has been formed by existing investors into the Centre for Quantum Computation and Communication Technology (CQC2T); namely USNW (which has invested $25 million into the centre), Commonwealth Bank of Australia ($14m), Telstra ($10m) and the Federal Government ($25m over five years as part of the National Innovation and Science Agenda).
The NSW Government today said it had pledged $8.7m towards the venture, the money coming from its Quantum Computing Fund which wasannounced in July.
SQCs board is made up of Michelle Simmons, UNSW Professor of Physics and director of the CQC2T; Hugh Bradlow, Telstras chief scientist; David Whiteing, Commonwealth Bank of Australias chief information officer; and Glenys Beauchamp, secretary of the Department of Industry, Innovation and Science.
Corporate lawyer and company director Stephen Menzies will act as interim chair.
We have a board which is very corporately focused, on developing and funding the engineering work to develop a ten qubit device. We will fund hardware. From that we will develop a patent pool which we hope will be without peer in the world, Menzies said.
In the first five years were very focused, the business plan is focused, on the patents associated with an engineered 10 quibit device. But beyond that we see that we have a stage on which we can develop across Australia, and Australian institutions, a broad quantum industry.
The company is seeking a further three shareholders to bring the total investment up to $100m.
The company will need additional moneys, and the business plan contemplates it will have additional shareholders who will join. All of whom we hope will bring strategic focus to the business and company, and also will bring their own enthusiasm and passion for quantum technologies, Menzies added.
SQC which will operate within the Centre for QTC at UNSW in Sydney has already started recruiting for forty roles, including 25 postdoctoral researchers, 12 PhD students, and a number of lab technicians.
Huge potential
Telstras Hugh Bradlow reiterated the telcos aim, revealed in June, to offer quantum computing to customers as-a-service.
Everyone knows that Telstra aims to be a globally leading technology company and if were going to do that we have to be at the forefront of 21st Century computing. [When realised] our customers are going to have access to a computer of unprecedented power and theyre not going to have the faintest idea of how to use it. So its Telstras aim to be in a position that, when that happens, we are skilled and knowledgeable about how to deliver those services to our customers. We look forward to taking [SQCs] products and putting them into our cloud services offerings in the future, he said.
Dilan Rajasingham, head of emerging technologies at Commonwealth Bank of Australia spoke of the huge potential of the technology.
Quantum computing is a revolutionary technology. It will transform the world as we know it. Weve invested more than $14m in quantum computing, because we believe in its future promise, we believe in its future capability, we believe in its potential as a differentiator. Not just for those of us involved, but also for Australia in general, he said.
We believe that quantum computing could be the foundation of a new high-tech ecosystem that can comes from Australia, our home, our biggest market and a key part of our identity. More than that though we are creating something newEven though the machine is still a few years away, the time for investment is now.
Senator Arthur Sinodinos, Minister for Industry, Innovation and Science, said the company would help give Australia a competitive advantage over the rest of the world.
"As a country we punch above our weight when it comes to knowledge creation but we really need to be doing more when it comes to commercialising our great ideas here in Australia. Its very important we do that. Thats not to say we commercialise every idea in this country but too many ideas do go offshore, Sinodinos said.
"Whatever sector of innovation we want to be really good in, we want to be world beaters. We want to create a competitive advantage, command a premium. And you do that by doing something new, something others find it hard to replicate or it takes them time to replicate, and by the time theyve replicated it youve moved on to something else. This is what this is all about, creating a world competitive advantage that we can build on with great upstream and downstream effects over time.
Global race
The SQC is now part ofa global race to build a quantum computer, building on the silicon-based approach of the CQC2T.
That race is hotting up. In July Microsoft cemented its long-standing quantum computing research relationship with the University of Sydney, with the signing of a multi-year investment deal understood to be in the multiple millions.
While nobody has yet built a proven quantum computer, a number of firms have already announced plans to make the technology commercially available.
Researchers at Googles Quantum AI Laboratory said in aMarchNatureeditorialthat the company would commercialise quantum technologies within five years. In the same month, IBM announcedits commercial'Q' quantum computing programwould deliver paid quantum computing services via the cloud to usersbefore the end of the year.
Microsoft, however, told Computerworld in July that it was still trying to figure out a business model for the technology.
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Tags Centre for Quantum Computation and Communication Technology (CQC2T)Arthur SinodinosNSW GovernmentCBAUNSWSilicon Quantum ComputingCommonwealth Bank of AustraliaHugh BradlowTelstraDilan Rajasinghamuniversity of new south wales
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Introducing Australia's first quantum computing hardware company - CIO Australia
IEEE Approves Standards Project for Quantum Computing … – Business Wire (press release)
PISCATAWAY, N.J.--(BUSINESS WIRE)--IEEE,the world's largest technical professional organization dedicated to advancingtechnology for humanity, and the IEEE Standards Association (IEEE-SA), today announced the approval of the IEEE P7130Standard for Quantum Computing Definitions project. Thenew standards project aims to make Quantum Computing more accessible to a larger group of contributors, including developers of software and hardware, materials scientists, mathematicians, physicists, engineers, climate scientists, biologists and geneticists.
IEEE P7130 will define terms related to the physics of quantum computing including quantum tunneling, super position, quantum entanglement, as well as other related terms and terminology that will be updated as technological advances are made.
"While Quantum Computing is poised for significant growth and advancement, the emergent industry is currently fragmented and lacks a common communications framework, said Whurley (William Hurley), chair, IEEE Quantum Computing Working Group. IEEE P7130 marks an important milestone in the development of Quantum Computing by building consensus on a nomenclature that will bring the benefits of standardization, reduce confusion, and foster a more broadly accepted understanding for all stakeholders involved in advancing technology and solutions in the space.
"IBM is part of quantum information's history, since its foundation more than 30 years ago. And we've been championing important terms, metrics, and scientific methods ever since," said Jerry Chow, manager, Experimental Quantum Computing, IBM Research and IEEE P7130 working group participant. "This standards project will help anyone from students to seasoned quantum scientists nucleate around a common language, while keeping up with the field's rapid pace of change, and further accelerate pioneering experiments and explorations in quantum computing."
"1QBit works with a variety of classical,quantumand otherwise non-standard processors, which necessitates communication between multiple external teams, across a wide range of industries, discussing many different types of computing systems, said Andrew Fursman, CEO 1Qbit and IEEE P7130 working group participant.IEEE P7130 "Standard for QuantumComputing Definitions"provides a valuable service to 1QBit, our partners inquantum computing, and the many industries with which we intersect."
Confusions exist on what quantum computing or a quantum computer means, added Professor Hidetoshi Nishimori of the Tokyo Institute of Technology and IEEE P7130 working group participant. This partly originates in the existence of a few different models of quantum computing. It is urgently necessary to define each key word.
To learn more about IEEE P7130, please visit the Quantum Computing Working Group landing page.
To learn more about IEEE-SA, visit us on Facebook, follow us on Twitter, connect with us on LinkedIn or on the Standards Insight Blog.
About the IEEE Standards Association
The IEEE Standards Association, a globally recognized standards-setting body within IEEE, develops consensus standards through an open process that engages industry and brings together a broad stakeholder community. IEEE standards set specifications and best practices based on current scientific and technological knowledge. The IEEE-SA has a portfolio of over 1,200 active standards and over 650 standards under development. For more information visit http://standards.ieee.org.
About IEEE
IEEE is the largest technical professional organization dedicated to advancing technology for the benefit of humanity. Through its highly cited publications, conferences, technology standards, and professional and educational activities, IEEE is the trusted voice in a wide variety of areas ranging from aerospace systems, computers, and telecommunications to biomedical engineering, electric power, and consumer electronics. Learn more athttp://www.ieee.org.
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IEEE Approves Standards Project for Quantum Computing ... - Business Wire (press release)