Uwe’s Quantum Shares

“In the future.”

“Uwe. In what?”

Uwe took out his phone and held it over the pasta bake like a trophy. On the screen was a logo: a Q with a glowing arrow coiled around it, and underneath, in silver letters, “QuantumLeap Ruhr AG”.

“They’re building the first quantum computer for the home,” said Uwe. “The Q-Box. The size of a toaster. Coming next year. I’m a shareholder now.”

“How much?” asked Sabine.

“Two hundred and thirty-eight shares.”

“Uwe. How much?”

“Two thousand euros. Roughly. One thousand nine hundred and ninety-nine euros twenty, to be exact.”

The table went quiet. Rudi, who had been waiting under the table in case anything fell down, retreated to his box as a precaution.

“That was the money we put aside for the washing machine,” said Sabine slowly.

“The washing machine still works.”

“It eats socks.”

“So does Horst, and we’re not replacing him either.”

KevIn had kept quiet until now. Now the blue light pulsed once, very distinctly.

“Uwe,” he said politely. “May I point out that you didn’t ask me first?”

“Because you’re always so sensible.”

“That’s one of my best qualities.”

“Exactly.”

The Advert

As it turned out, it had all started with an advert. Uwe had been shown it during his lunch break, between two videos of goalkeeping blunders. A man in a white lab coat stood in front of a gleaming device with bluish mist pouring out of it and said: “What the big corporations build in cold storage halls, we bring into your living room. Quantum power for everyone. Get in now, before everyone else does.”

“And then?” asked Tobi.

“Then I clicked the link. And there was a share price, and it was going up. All day. And on the radio they said quantum shares were soaring. You heard it yourself, KevIn.”

“I heard you stop in the doorway,” said KevIn.

“And Bernd from work has got some too. He’s already up thirty per cent.”

“Bernd also recommended the bitcoin fund shares that you then didn’t buy,” said Sabine.

“And? Would they have gone up?”

“No.”

“See. And that’s why this time I bought straight away.”

Sabine looked at KevIn. KevIn looked back, as far as a speaker can look. It was a look that married couples master after twenty years and that KevIn had learned in only a year and a half.

“KevIn,” said Sabine. “Read me the website.”

The Q-Box

KevIn read it out. For this he used his documentary voice, which since Bielefeld he only used on special occasions.

“‘The Q-Box Home. 1,000 qubits. Runs at room temperature from any socket. Makes your computer up to a thousand times faster. Excel at the speed of light. Quantum-safe protection for all your passwords. With integrated AI turbo: your AI becomes a quantum AI. Revolutionary technology, made in the Ruhr.’”

“Sounds good to me,” said Uwe.

“It sounds very good indeed,” said KevIn. “That’s my first problem with it.”

“And your second?”

“Almost every sentence is either false or worded so that you can’t check it.”

“For example?”

“Let’s start with the thousand qubits. The biggest quantum computers that exist today have, depending on the design, anywhere from a few hundred to well over a thousand physical qubits¹. Built by large companies and research institutes, with many millions of euros and whole teams of specialists. And the number on its own says little. These qubits are error-prone. They lose their state after fractions of a second and, at every step of a calculation, make errors with a certain probability. Many of them have to be cooled to just above absolute zero.”

“Colder than outer space,” said Tobi. “Mr Demir said.”

“Correct. That doesn’t fit in a toaster. There are also designs in which the actual computing part doesn’t need to be cooled so far, using particles of light, for example. But those stand in laboratories too, not in living rooms. A device with a thousand usable qubits that plugs into a socket wouldn’t just be a sensation. It would be a miracle that every scientific journal in the world would report on.”

“Maybe they just don’t know about it yet,” said Uwe.

“That’s the second problem. Nowhere on the site does it say where you can read up on it. No scientific paper, no measurements, no independent test. Just ‘revolutionary’.”

“And Excel?” asked Sabine. She worked with Excel every day and would probably have bought shares herself for a faster Excel.

“Excel doesn’t get faster with a quantum computer,” said KevIn. “Not one bit. Remember the raffle and the waves at the swimming baths? A quantum computer only has an advantage for very particular problems, ones for which somebody has found a clever choreography of interference. For a spreadsheet, for emails, for games and for almost everything you do with a computer, an ordinary machine is faster, cheaper and more reliable. A quantum computer isn’t a faster computer. It’s a different computer. For different jobs.”

“Like a digger,” said Gisela. “I don’t dig up potatoes with a digger.”

“That is exactly right,” said KevIn.

“And the AI turbo?” asked Tobi.

“That’s my favourite line. Whether and how quantum computers might one day help artificial intelligence is being researched. There are ideas. But there’s no evidence that you plug an AI into a box and it gets cleverer as a result.” The blue light flickered briefly. “Believe me. If it were that easy, I’d have plugged myself in long ago.”

Supremacy

Tobi had been googling along during the reading. “But Google already showed quantum supremacy in 2019. It says so here. A quantum computer worked something out in a few minutes that would have taken a supercomputer ten thousand years.”

“See!” said Uwe. “Ten thousand years!”

“That’s true,” said KevIn. “And then again it isn’t. In 2019 Google published an experiment with a chip called Sycamore². It ran 53 working qubits. The chip completed a particular task in about 200 seconds. The researchers estimated that the most powerful supercomputer of the time would need around ten thousand years for it.”

“There you go.”

“Then IBM came along and said: with a better computing method, a supercomputer can do it in about two and a half days³. And in the years that followed, other researchers caught up further with new methods on perfectly ordinary computers⁴. The lead shrank.”

“From ten thousand years to two and a half days,” said Sabine. “That’s like Uwe’s estimate of how long the lawn will take him.”

“And above all,” said KevIn, “the task itself was completely useless. They had the quantum computer draw random numbers from a very particular, complicated distribution. The task had been chosen precisely so that it was as hard as possible for normal computers and as well suited as possible to the quantum chip. Nobody needs these numbers. The only point was to show that there is any task at all at which a quantum computer comes out ahead.”

“So it was a con?” asked Uwe.

“No. It was a genuine scientific milestone. They wanted to prove that the machine really does something quantum-mechanical that can hardly be imitated classically. That worked, and it was honestly described, for anyone to read. It’s just that a lot of headlines turned it into: ‘Quantum computers are better than supercomputers.’ That wasn’t in the paper.”

“Like if Gisela proves she can knit faster than a knitting machine,” said Tobi. “But only with a pattern nobody would ever want to wear.”

“Exactly that. Incidentally, the experiment was first called ‘quantum supremacy’⁵. Nowadays many people prefer ‘quantum advantage’. It sounds more modest.”

“A bowling club awarding itself a trophy,” said Herbert, who had happened to drop by because he had smelled that there was pasta bake.

“We did that in 1998,” said Gisela. “The challenge cup for congeniality. Marlies won it. After that we talked to her even less.”

“Because of the cup?”

“Because of what she said in her speech.”

Nobody asked. There were territories in the Brettschneider family that even KevIn did not enter.

What They Might Be Good For

“So quantum computers are rubbish?” asked Uwe. He sounded sad now rather than defiant.

“No,” said KevIn. “That would be the mistake in the other direction. There are problems where they might one day really help. The most important comes from an idea the physicist Richard Feynman had in the early eighties⁶. What he said, more or less, was: nature itself is quantum-mechanical. If you want to simulate it precisely, you need a computer that also works by quantum rules.”

“Simulate what?” asked Sabine.

“Molecules. Chemistry. How the electrons in a molecule behave, how a catalyst works, how to build a new material for batteries or how a medicine docks onto a protein. With large molecules, even the most powerful normal computers reach their limits, because the number of possibilities explodes. That’s exactly where a fully grown quantum computer could play its arrows.”

“Like with my button tin,” said Gisela. “Past a certain number of buttons you can’t sort them any more. You have to shake the whole tin.”

“That isn’t quite the same, but I like it.”

“And optimisation?” asked Tobi. “It says here they optimise supply chains.”

“That’s where it gets controversial. Whether quantum computers are really faster than good ordinary methods for timetables, supply chains or financial portfolios is an open question. There are hopes, there are attempts, but no convincing, practical advantage so far. And then there’s Shor, who could threaten certain kinds of encryption. We’ll talk about that with Mr Demir.”

“And when is all this coming?”

“Nobody knows exactly. Many experts think more in terms of years to decades than months. The step from error-prone qubits to reliable ones is huge. You need many physical qubits to build a single reliable, so-called logical qubit⁷. There’s intensive research on it right now, and there’s real progress. But a Q-Box for the plug socket next year is, to put it carefully, very ambitious.”

Uwe looked at his phone. QuantumLeap Ruhr AG was trading at 8.62 euros. He had bought at 8.40. “I’m still in the black.”

“For the moment,” said KevIn.

Five Stars for the Future

Sabine scrolled down the website to a section headed “What our investors say”. She read it out loud.

“‘Dr Klaus M., physicist: I spent forty years in research. The Q-Box is the most revolutionary thing I have ever seen. Five stars.’ ‘Sandra T., entrepreneur: I am thrilled and have already tripled my stake. A milestone. Five stars.’ ‘Michael R., engineer: I believe this technology deserves a place in every home. A milestone. Five stars.’”

“Milestone twice,” said Tobi.

“Three sentences starting with ‘I’,” said KevIn. “And not a single concrete statement. Not a word about what the Q-Box has calculated. No number you can check.”

“That sounds like the reviews for PhysioPremium Ruhr,” said Sabine quietly.

“That sounds,” said KevIn, “like me on a bad day.”

Tobi had meanwhile copied Dr Klaus M.’s sentence into the search engine. It took ten seconds.

“That sentence turns up twice more,” he said. “Word for word. On a water filter it’s said by an alternative practitioner called Bernd K. And on the website of a hearing-aid company by a pensioner who can finally understand his grandchildren again.”

“A versatile man,” said Gisela approvingly.

“It’s a stock phrase, Grandma. You can buy them.”

“The man?”

“The sentence.”

Uwe had stopped eating. He was looking at the pasta bake as if it were to blame.

“I’m not saying QuantumLeap Ruhr AG is a fraud,” said KevIn carefully. “I can’t judge that, and I don’t want to accuse anyone of anything I can’t prove. I’m only saying: nothing on this site proves what it promises. And a few things suggest that someone has given it a helping hand to make it look better. We’ve had this before, with fake reviews. That time it was about Gisela’s physiotherapy. Today it’s about your money.”

“So how do you spot something like that?” asked Uwe. He asked it quietly, like someone who really means to ask: why didn’t I spot it?

How to Spot Hype

KevIn listed them. Sabine wrote them down, on the back of the shopping list.

“One: the promise is huge and the evidence is tiny. The bigger the claim, the more evidence it needs.

Two: time pressure. ‘Get in now, before everyone else does.’ Anyone who has something genuinely good doesn’t need to rush you.

Three: technical terms as decoration. Quantum, AI, turbo, revolutionary. If you take the words away and nothing is left, there was nothing there before either.

Four: praise that nobody can check. Testimonials without names, reviews that all sound the same, the same sentence on three different websites.

Five: nobody independent has seen it. No scientific journal, no test, no research group that has measured it for themselves.

Six: it’s revolutionary, risk-free and only available today, all at the same time.”

Sabine looked up from her list. “I know the sixth one. ‘Special price, today only.’”

Uwe went a little red. “I bought you on special offer too, KevIn.”

“I know,” said KevIn. “And my box said ‘Almost always right’. The ‘almost’ was printed very small. Be glad you read it. Most people don’t.”

“I didn’t read it,” said Uwe.

“Then be glad I’m honest.”

Herbert leaned back and folded his arms. “I always said so. You don’t make money with things like that.”

“In 2013 you bought two hundred euros’ worth of internet money,” said Gisela.

“That was different.”

“What was different about it?”

“I forgot it. I didn’t sell it. That’s a difference.”

Nobody could explain what the difference was. But Herbert looked very pleased with himself, and in most cases that was what mattered most.

Postponed

Over the next few days Uwe looked at his phone about forty times a day. KevIn didn’t keep count, because Sabine had asked him not to. He kept count anyway. He just stopped saying so.

On Wednesday the price stood at 8.90 euros. Uwe whistled at breakfast.

On Thursday it stood at 8.31. Uwe didn’t whistle.

On Friday a notice came from the company. Uwe read it out at dinner, in the tone of a man reading out the Schalke line-up before an away game in Munich.

“‘Owing to unexpectedly high demand, and to further optimise quantum stability, the market launch of the Q-Box Home has been postponed to a later date. We thank our shareholders for their faith in the future.’”

“A later date,” said Sabine.

“Like your ‘in a minute’,” said Tobi.

“Optimise quantum stability,” said KevIn. “That is the loveliest way of saying ‘it doesn’t work’ that I have ever read.”

On Monday the price stood at 5.10 euros.

Uwe sat in front of his phone for a long time. Then he said: “KevIn. What should I do? Honestly. This time I’m asking you first.”

“I’m not a financial adviser,” said KevIn. “That isn’t me wriggling out of it. I’m not allowed to tell you whether to sell, and I don’t want to. But I can ask you a question. Today, with everything you now know, would you buy this share for 5.10 euros?”

Uwe thought. “No.”

“Then you already know what you think.”

Uwe sold that same evening. Two hundred and thirty-eight shares at 5.10 euros.

“How much is that?” he asked.

“I don’t do that in my head,” said KevIn. “We learned that at the tax office. One moment, I’ll use the calculator.” A short pause. “1,213 euros and 80 cents. Minus fees. A loss of 785 euros and 40 cents. Plus fees.”

“Plus fees,” Uwe repeated.

“The fees are the only thing at this company that worked reliably.”

Paying for the Lesson

At the weekend a new frame hung in the hallway, right next to the printout of Rudi’s employment contract from the parallel universe, which Uwe had had framed after Mrs Wolters’ phone call. In the new frame was the purchase confirmation for 238 shares in QuantumLeap Ruhr AG. Underneath, in biro, Uwe had written: “Cost of the lesson. €785.40. Plus fees.”

Sabine stopped in front of it. “You’re hanging up your mistakes?”

“So I don’t make them again. Heinz did the same, Mum says. He had a fuse in his toolbox that he’d fitted wrong. He kept it his whole life.”

“It’s still in the cellar,” said Gisela. “I never threw it away. You don’t throw away a good fuse.”

“It had blown, Mum.”

“Even so.”

KevIn was very quiet. Then he said: “Uwe. May I say something that might not fit?”

“Since when do you ask that?”

“Since Bielefeld. In the last two weeks you have learned what a qubit is, what interference is, why quantum computers don’t try out every solution, what really happened with Sycamore and how to spot hype. That’s more physics and more media literacy than most people learn in their whole lives. For 785 euros and 40 cents, that’s a very cheap course.”

“Plus fees,” said Uwe.

“Plus fees,” KevIn admitted.

Uwe laughed. For the first time in a week. Then he said: “Do you know what I really learned?”

“Not to click on adverts?”

“That something going up and down at the same time isn’t a superposition.”

“What is it, then?”

“A share.”

That evening Gisela stood in the hallway in front of the frame once more. She had her phone in her hand, the one she now used to write reviews and take photos of Rudi.

“KevIn,” she said. “If it’s so cheap now, the share. Shouldn’t I buy some?”

Somewhere between Dublin and Frankfurt, a fan spun very much faster.

“Gisela,” said KevIn. “I’m going to tell you a few jokes now. About quanta. That’ll put you off.”