Simon Benjamin
Professor of Quantum Technologies, University of Oxford · 1 appearance on the record.
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Simon Benjamin leads the Quantum Technology Theory Group at the University of Oxford, researching quantum computing architectures and fault tolerance. In 2017, he co-founded Quantum Motion, a company developing fault-tolerant quantum processors using silicon CMOS technology.
26statements → 18claims → 14claims resolved → 100%fully supported → 3.77/5average certainty → 1.65/5average debate potential →
14 supported 0 partly supported 0 contradicted 4 not checkable as stated how the 18 claims stand · each chip opens the sources
4 predictions · 14 assertions · 2 opinions · 4 insights · 2 disclosures · every statement was checked. The predictions and assertions are the 18 claims: statements the public record can support or contradict. 14 are resolved, and 4 name no date, number or outcome precise enough to check. Everything else (opinions, insights, what ifs, disclosures) can never be settled by the record, so it carries no assessment.
The record, in short
What the tape says about how Simon argues and how the claims held up. Everything they said, and everything said about them, is in the tabs below.
Their most notable supported claim
Benjamin: 50-qubit supremacy devices will launch within a year but lack practical utility
“On the other hand, what we believe is about to happen in the coming year is that people will start to bring out qubits, ah, sorry quantum devices that are at or just a little bit over the quantum supremacy threshold. This number, a lot of people are racing to …”
Expressed certainty vs assessment result
weighted support: a fully supported claim counts one, a partly supported claim counts half. Each filled bar is clickable and opens exactly those claims; "none yet" means nothing said at that certainty level has resolved yet
Everything Simon Benjamin said on the Y Combinator Startup Podcast that made the record, most notable first. Filter by type, assessment or year in the ledger →
Benjamin: Theorists have found no useful application for a 64-qubit quantum computer
“The theorists have not worked out anything that a 64 qubit quantum computer can do that's super useful.”
Benjamin's team plans to scale using networked five-qubit modular units
“We actually are planning to build a machine, which will be made out of modules, which each one is a small quantum computer, and by the way, so small that on its own, it's not good for anything. Even as few as five qubits, right? And then we have modules, and w…”
Benjamin: Modular architecture is the only viable route to rapid quantum scaling
“And in fact, this network approach is, I think the only one that if you wanted to Manhattan project it, right, or moonshot it, you're one of these big projects that have happened in the past where you have a goal that's extremely challenging and you just decid…”
Benjamin: Ion traps are the gold standard of qubits
“So they are actually the gold standard of qubits.”
Benjamin: Quantum applications needing fewer than 50 qubits can be simulated classically
“There's no point, if you think you've got a clever idea for what to use a quantum computer for, and that's going to change the world, if your idea involves much less than 50 qubits, you're wrong. Because, ah, you may have a very nice idea, but what we would do…”
Benjamin: 50-qubit supremacy devices will launch within a year but lack practical utility
“On the other hand, what we believe is about to happen in the coming year is that people will start to bring out qubits, ah, sorry quantum devices that are at or just a little bit over the quantum supremacy threshold. This number, a lot of people are racing to …”
Benjamin: Entanglement distillation allows low-quality links to achieve high internal fidelity
“As long as your boxes have a very good memory, they do have a very good memory, as long as they have very good quality internal operations, which they do have, then you can take a poor quality link and boost it by using it a few times into effectively a very g…”
Benjamin: Quantum hardware will soon reach behaviors impossible to classically simulate
“We are now getting on the verge of getting machines that will behave in ways that cannot be predicted, cannot be simulated. We'll be in the regime where we're genuinely discovering how the machine behaves by having one.”
Benjamin: Quantum error-correction threshold is now around 99% fidelity
“So now the threshold is about 99%. If you've got 90, if things work correctly in your quantum computer, 99% of the time, that's the turning point.”
Benjamin: Oxford quantum researchers achieve 99.9% gate fidelity
“But 99.9, which is what the guys here in Oxford can do, is 10 times better than the threshold.”
Benjamin: Kitaev surface code is the go-to quantum computer architecture
“Especially something called the Kataev surface code, which is, at the moment, the go-to solution for how we would build a quantum computer.”
Benjamin: Oxford Holds World Record for Ion Trap Quantum Control
“But the one that I mentioned that we have the world record for the best control, is this thing called an ion trap, which sounds very technical.”
Benjamin: Trapped-ion qubits achieve 50-second to 10-minute coherence times
“So for the superconducting qubits that many researchers are excited, and we do do work on that here in Oxford as well the decay time, the amount of time that can go by before the wonderful zero one superposition just degrades, is the tiniest fraction of a seco…”
Benjamin: First useful quantum algorithms in the coming year will skip error correction
“Now, for the first quantum algorithms that we made, you know, the first serious ones that might do something useful, that perhaps we'll see in the coming year, ah, that's probably going to be the approach.”
Benjamin: Building million-qubit quantum computers could take over a decade
“What we've worked out on paper is stuff that needs pretty big computers, and we don't know how long it would take to get there. You know, maybe, hopefully not decades, but it could take definitely more than a decade to get to the point where we have millions o…”
Benjamin: Commercial interest in academic quantum research saw a sea change
“Just in the last three years, we've had tons more interest from companies who come to us as academics and say, look, can we jointly work on something with you? I mean, that's really been a sea change.”
Benjamin: Ancilla qubits detect errors without collapsing main quantum data
“Basically this trick of not looking for errors where they are, but looking to one side, because you've basically done a separate little calculation that now in the, what we call ancilla qubits, it tells you just one thing, the one thing you do legitimately nee…”
Benjamin: Quantum computer design must treat all hardware operations as untrustworthy
“We must assume that everything is untrustworthy. Some things are worse than others. So measurement of a single qubit might be a bit more reliable than say the two qubit gate, but they all have a number on them that says how dodgy they are.”
Benjamin: 1990s quantum fault-tolerance threshold required 99.9999% fidelity
“And now the threshold when these results were first discovered in the nineties was about 10 parts per million. So I have a many nine, 99.9999 was the kind of level of precision that you would have to have in order to control your quantum computer and take the …”
Benjamin: Topological codes brought quantum fault tolerance down to 99% threshold
“So that was responsible primarily for moving from the multiple nines to the 99% threshold.”
Benjamin: Oxford Has ~200 Quantum Researchers in World-Leading Facility
“Oxford is actually one of the biggest research facilities in the world for quantum. We've got something like 200 people working on this, and so we're working on a bunch of different stuff.”
Benjamin: Simulating 45 qubits classically requires 0.5 petabytes of RAM
“So, 45 qubits required 0.5. This wasn't my work. This was work elsewhere in the community. It required 0.5 half a petabyte of RAM, basically.”
Benjamin: Quantum codebreaking requires millions of physical qubits due to error correction
“Breaking codes is in the category of things that needs at least thousands of qubits. But because it's a big, tough, long-running task, it also needs this whole error correction thing to be going on. And that boosts the size of it, because once you say, oh, wai…”
Appearances (1)
| Episode | Date | Speaking time |
|---|---|---|
| Simon Benjamin on Architectures for Quantum Computing · Y Combinator | May 25, 2018 | 1h 8m |