Collaborate Disseminate
Physicists at the Max Planck Institute have developed an efficient new method to drive the quantum entanglement of photons, and demonstrated it by entangling a record number of photons. The technique could be a boon for quantum computers.Continue Readi… Continue reading Quantum entanglement record set with largest cluster of photons so far
And THIS is why you don’t knit your own home-made encryption algorithms and hope no one looks at them. Continue reading Post-quantum cryptography – new algorithm “gone in 60 minutes”
Researchers in Germany have demonstrated quantum entanglement of two atoms separated by 33 km (20.5 miles) of fiber optics. This is a record distance for this kind of communication and marks a breakthrough towards a fast and secure quantum internet.Con… Continue reading Record-setting quantum entanglement connects two atoms across 20 miles
Scientists have created a “quantum flute” that can coax photons to move in sync and interact with each other, which they almost never do in nature. The device could help improve future quantum computer designs.Continue ReadingCategory: Physics, Science… Continue reading “Quantum flute” gets light moving in way never seen before
Engineers in Sydney have demonstrated a quantum integrated circuit made up of just a few atoms. By precisely controlling the quantum states of the atoms, the new processor can simulate the structure and properties of molecules in a way that could unloc… Continue reading Atomic-scale quantum circuit marks major quantum computer breakthrough
Quantum computing may have just taken a major step forward, as a supercomputer facility in Australia becomes the first to have a quantum computer integrated into it. The quantum processor, developed by German-Australian start-up Quantum Brilliance, run… Continue reading Diamond-based quantum computer paired with supercomputers for first time
Scientists in the Netherlands have made a major step towards quantum computer networks by teleporting quantum information between two nodes that didn’t have a direct link to each other. The breakthrough heralds a faster and more secure communication sy… Continue reading Quantum teleportation achieved between non-adjacent network nodes
DNA is known to mutate regularly, for better or worse, driving both evolution and disease. Researchers at the University of Surrey have now found evidence that some of these spontaneous mutations could be caused by the spooky realm of quantum mechanics… Continue reading Quantum tunneling could drive random DNA mutations, says new study
A TU Delft team has demonstrated a one-way superconductor that gives zero resistance in one direction, but blocks current completely in the other. The discovery, long thought impossible, heralds a 400x leap in computing speed and huge energy savings.Co… Continue reading One-way superconducting diode has massive implications for electronics
Answers to question RSA key length vs. Shor’s algorithm suggest that e.g. 2048 bit RSA encryption would be trivially broken with 4099 qubit quantum computer using Shor’s algorithm (best known implementation of the algorithm requiring 2n+3 qubits).
Is this really true? If I’ve understood correctly, the number of gates (logically quantum operations) needed would be around log(2^2048)^2×log(log(2^2048))×log(log(log(2^2048))) which is roughly 2.9×10⁷. Considering that not even classical computers can execute any operations with 2.9×10⁷ gates using single piece of input data it really doesn’t make sense to assume that such a high number of gates could be operated by quantum computer in non-trivial time.
I would assume that for quantum computer to execute one step executing the Shor’s algorithm would need to pass (logically) one input through all those gates which would be analogous to classical computer executing enough computer code to pass one 2048 bit input through 2.9×10⁷ gates. Because information cannot travel faster than speed of light and gates have non-zero dimensions, this cannot happen in trivial time. And if you use photons for qubits in the quantum computer, wavelength probably sets minimum dimensions for a gate regardless of manufacturing abilities.
And if you need any error correction between the gates, that will require extra space and hence increase latency, too.
In addition, if I’ve understood correctly, to actually factor big numbers with Shor’s algorithm you need to use classical computer to generate a random guess and Shor’s algorithm will then use that guess to maybe emit the data need to compute the factors. How many guesses on average you would actually need for factoring numbers used in 2048 bit RSA?
Has there been research about potential practical runtime of a big physical quantum computer trying to execute Shor’s algorithm for factoring big numbers? Does that really support the interpretation that you can simply ignore the processing time regardless of the size of the numbers?