DEF CON 33 - Post Quantum Panic: When Will the Cracking Begin, & Can We Detect it? - K Karagiannis
Due to recently published algorithmic improvements (1399 qubits @ 2048 bit key length for Shor’s) and leaps being made in quantum computing hardware (IBM Starling @ 200 logical qubits in 2029, and IBM Blue Jay @ 2000 logical quibits from 2033 and on), encryption is in danger of State-sponsored and high end-criminal attacks as soon as 2030. Particularly susceptible are crypto-currencies like Bitcoin, which rely on the Elliptic Curve Discrete Logarithm Problem (ECDLP) and are attackable by Shor’s factoring capability on a predictably feasible quantum computer.
Its 2025 and to my knowledge we have a total of zero quantum computers that can even do basic first grade math.
There was a paper recently about a stable 6100-qubit system, so the trajectory is plausible. If 1399 qubits is needed for 2048-bit Shor’s, this would already meet that by a wide margin – though obviously this is a research system that AFAIK cannot do actual computations.
https://www.livescience.com/technology/computing/quantum-record-smashed-as-scientists-build-mammoth-6-000-qubit-system-and-it-works-at-room-temperature
As you said, this research isnt functional. The TLDR of all of the following is that to my understanding the record holding quantum computer currently has 4 (four) qubits.
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From the original source (caltech)
So yeah, they arent at the step where they can actually do anything with the qubits they created. 6100 physical qubits also doesnt equal 6100 logical qubits. https://en.wikipedia.org/wiki/Physical_and_logical_qubits
Im a total non expert on quantum things, but from the looks of it, the most efficient systems (at Microsoft) still need many times the amount of physical to create a single logical qubit.
Its also impossible to read up on this stuff, because lots of research for “quantum computers” actually just algorithmically simulates the logical qubits on standard non quantum hardware. So if you search just for “largest logical qubit system” you get lots of garbage and searching for physical qubits gives you research like this 6,100 number that cant be converted into a realistic number of logical qubits, because the overhead needed for error correction varies drastically between techniques.
What you really wanna know is the largest set of functional logical qubits that actually relies on physical qubits. And the answer to that seems to be 4. Whats needed to break RSA-2048 is probably multiple thousands of those stable, error free logical qubits.
https://en.wikipedia.org/wiki/Quantinuum#H-Series
Even if it’s 8 physical qubits to 1 logical qubit, 6100 qubits would get you 762 logical cubits.
All I’m saying is that the technology seems to be on a trajectory of the number of qubits improving by an order of magnitude every few years, and as such it’s plausible that in another 5-10 years it could have the necessary thousands of logical qubits to start doing useful computations. Mere 5 years ago the most physical qubits in a quantum computer was still measured in the tens rather than the hundreds, and 10 years ago I’m pretty sure they hadn’t even broken ten.
Its really not on that trajectory tho. Huge inflated numbers of nonfunctional physical qubits are just a way to get funding. Its like AI bros boasting about how much data their LLM model sucked in. The number of usable qubits hasnt changed at all basically. They are still in the stage of figuring out how it even works. Compared to traditional computers, they are at the stage of trying to invent the transistor. Yes in 20-30 years it will maybe be useful, but only if they dont hit physical limitations that prevent scaling. And then the question is FOR WHAT? Dead people cant make use of quantum computers and dead people is what we will be if we dont figure out solutions to some much more imminent, catastrophic problems in the next 10 years.
I mean, the number of logical qubits has gone from basically zero not too long ago to what it is now. The whole error correction thing has really only taken off in the past ~5 years. That Microsoft computer you mentioned that got 4 logical qubits out of 30 physical qubits represents a 3-fold increase over the apparently previous best of 12 logical qubits to 288 physical ones (published earlier the same year), which undoubtedly was a big improvement over whatever they had before.
Strange thing to say. There’s enough people on the planet to work on more than one problem at a time. Useful quantum computing will probably help solve many problems in the future too.