Quanta are sensitive little beings. Under the influence of peer pressure, they behave completely differently when someone is watching. Quantum mechanical measurements behave completely differently from classical measurements, i.e. the ones we know from everyday life. That’s what we’re going to talk about today: The pitfalls and subtleties of quantum mechanical measurement – and why they are so fascinating!
I recently read the book “The Circle” by Dave Eggers. It’s about a Facebook-Twitter-like Internet company called “The Circle” that wants to create complete transparency and networking – privacy, unfortunately, falls by the wayside. The quote above is by one of the Circle bosses and he uses it to justify his ubiquitous surveillance. I am sure that we would all answer this question affirmatively. We behave differently under surveillance than when we are alone. So does that mean that pure observation influences our behaviour?
It may surprise you: quantum technology is more than just quantum computing. I like to get upset that quantum technology is often equated with quantum computing because there are many ways to improve technology using quantum physics. Here, I want to talk about quantum computing’s big, modest sister: quantum simulation. They are closely related, and…
As Andy Williams sang: It’s the most wonderful time of the year! No, not Christmas – the Nobel Prizes were awarded! This year, the Nobel Prize Committee had a special gift for us: A Nobel Prize for Quantum Physics! Exactly 10 years after the last big Nobel Prize was awarded to the quantum physicists Serge Haroche and David Wineland. No question that we have to take a closer look.
Even scientists are only human. That’s why success stories often read like a comic book: great heroes fighting for the good of humanity. From another perspective, however, it sometimes seems more like the nagging of old white men arguing over who is right. We have already seen a few examples of this: Boltzmann and Planck fighting over entropy, Thomson and Rutherford decoding the atom, Newton and the rest of the world racking their brains over the nature of light. And the Stern-Gerlach experiment, which celebrated its hundredth anniversary this month and which is a milestone of quantum physics, was ultimately the invention of a scientist who desperately wanted to be right.
Polar ice, the moon, the quantum world – what do these places have in common? There is no Wi-Fi? Possibly. It’s uncomfortable? Probably. They are uninhabited? Not at all! All these places have (allegedly) already been seen by a certain living being. Sometimes by choice, sometimes by design, sometimes by accident. What kind of creature is it that hangs around in such exotic, hostile places? It is small, chubby and it’s name: Tardigrade! In 2014, tardigrades were found in the Arctic that had been “hibernating” for over 30 years. Since a crash landing of an Israeli space probe in 2019, a few tardigrades have been lying on the moon. And according to a group of researchers, tardigrades have now also made the leap into the quantum world! But is that really true?
Santa’s gift tour is a headache for children every year: How does he manage to visit every child in the world in a single night? But Santa’s travel speed is not the only problem. I wonder: how does he know if the child whose chimney, balcony or front door he is standing in front of has been naughty or nice? Does he carry around the naughty-nice-list in paper form? Is he in radio contact with the North Pole? Or does he have a completely different method? We will ask the question: Is communication faster than the speed of light possible?
Everyone is talking about quantum computers. Do you sometimes feel like you’ve missed the boat and no longer dare to ask how a quantum computer actually works and what it’s supposed to be good for? Then my blog series “FAQ: Quantum Computer” is for you! Many news articles on quantum computing do not (or no longer) go into sufficient detail about the new quantum machines, which quickly leads to misunderstandings and confusion.
I have gone into the details of the “miracle machines” in three articles. Here you will find an overview of the questions I have tried to answer – including a short version of the answer.
The quantum computer as the holy grail: with it everything will be better, everything will be faster, unsolvable problems will become child’s play, banks beware – your encryption is finished! Is that really the case? In what are quantum computers really better than classical computers and in what are they perhaps not? In my series “FAQ: Quantum Computers” series, I try to clear up common misconceptions and erase question marks. This is the last part of the series and it’s about the differences between classical and quantum computers.
Many articles on quantum computing are rushing quite a lot. “A qubit can be in the states 0 and 1 at the same time, and that’s why quantum computers are better than classical ones.” Sure…? Um, no, that was a bit too quick. In my series “FAQ: Quantum computer” I try to clear up common misconceptions and erase question marks. This article is about how to make a quantum computer out of many qubits.