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Scientists Break Quantum Entanglement Record At 18 Qubits (zmescience.com)
hackingbear writes: Researchers at the Chinese University of Science and Technology have demonstrated stable quantum entanglement with 18 qubits, surpassing the previous world record of 10, also held by the same team. This represents a step toward realizing large-scale quantum computing, according to a recent study published in the journal Physical Review Letters. Physicist Pan Jianwei and his colleagues achieved the new record by simultaneously exploiting three different degrees of freedom-paths, polarization and orbital angular momentum of six photons, the fundamental particle of light. The outcome combination resulted in a stable 18-qubit state. Full control over the number of entangled particles determines the fundamental ability for quantum information processing, according to the study. There are early-stage quantum computers out there that argue more qubits -- such as IBM's 50-qubit machine and Google's 72-qubit Bristlecone, but in those cases, the individual quantum states of the qubits aren't (fully) controllable. "The team's next step will be to realize a 50-qubit entanglement and manipulation," according to Wang Xilin, a member of the team. The same research team also held the world record on quantum communication distance as well as operating the world's first quantum communication satellite.
The bigger the system you can stabilise, the bigger the questions you can answer immediately (i.e. factorise this 2048-bit number), and you can answer ALL such questions in that same timeframe (so once you can break one 2048-bit key instantly, you can break them all instantly).
That is simply not true.
http://www.quantumforquants.org/quantum-computing/limits-of-quantum-computing/
"Classical" is the term use by physicists to refer to pre-GR and pre-QM physical theories. That you don't know it it's not his fault.
Actually quite a few more. Even to break an ECC modulus, they need about 300 more. With the scaling of around 1Qbit/year since 2001 (when they factored 15 on a 7 Qbit machine), my guess would be that it will take a few centuries to get there.
Silicon scaled exponentially almost from the beginning and continued to do so for a long time. That is what makes it powerful today. QCs have never scaled better than linearly and are still at a ridiculously useless size as a consequence, after about 30 years of applied research. They may also well scale sub-linearly. The whole thing would have been dropped as a dead-end a while ago, except that many humans run after every hype that tickles their fantasy.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
The answer is immediate. O(1). Not O(n) or worse as in any classical system.
I'm not sure how you could have come to believe this ... but it's incorrect. Quantum computers can use algorithms that scale better than classical ones - say, scaling as O(n^2) rather than O(e^n) - but they don't generate an answer *immediately*.
For example, Shor's algorithm for factorisation runs in O((logN)^2 * loglogN * logloglogN) time, while the classical general field number sieve which does the same thing runs in (roughly) O(e^(1.9 * (logN)^0.33 * (loglogN)^0.66) time. That's a massive improvement - going from subexponential to polynomial time - but it's still not instant.