The world is on the brink of a quantum revolution - or is it perhaps already here?
Per Delsing has spent nearly 40 years exploring the boundaries and possibilities of quantum mechanics. In his William Chalmers Lecture, “Why is everyone talking about quantum computers?”, he will be talking about how quantum computers will affect our everyday lives, how Sweden can be made a front runner in quantum technology and when we can expect the great quantum revolution to begin.
Per Delsing decided to venture into the unknown landscape of science and technology as a nine-year-old as the black-and-white images from history's first moon landing captivated him from the childhood home TV sofa. Today, he’s the leader of Sweden's largest quantum technology venture, the Wallenberg Center for Quantum Technology, and is seen as a national pioneer in the field.
The 1,5 billion SEK investment aims to put Sweden at the forefront of quantum technology. In the limelight is the building of a quantum computer that today has reached 25 qubits but will eventually go up to 100.
“Now we’re working hard to make it work properly. At the same time, our theoreticians are working on a number of problems that we will solve once the computer works,” says Per.
Being in two places - at the same time
But what exactly is quantum mechanics and how does a quantum computer work? Two tricky questions, to say the least, that Per will be answering in the course of the 45-minute lecture.
“Don't you sometimes wish you could be in two places at the same time? Of course, you can't, but a quantum system can,” says Per.
The difference between quantum computers and ordinary computers lies in their building blocks. An ordinary computer's smallest information carrier is called a bit and can either have the value of 1 or 0. Quantum computers' quantum bits can have both the value 1 and 0 - at the same time.
“The phenomenon is called superposition and means that the total number of possible states is doubled for each qubit, with an exponential increase. This means that if you have a quantum computer with 300 qubits, you can represent more numbers than there are particles in the Universe,” explains Per.
Can solve difficult optimization problems
The computing power of such a quantum computer will be enormous and make it capable of tackling complex mathematical problems that no supercomputer today can handle. The areas of application in society are many, and important.
“With such computing power, quantum computers can solve very difficult combinatorial optimization problems where you have few variables but many ways to solve the problem. One example is the optimization of air traffic, where quantum computers can develop an algorithm that provides the best and cheapest way to plan the logistics for a given number of routes and aircraft. It may also be about protein folding, i.e. how to get proteins to "curl" together, which is important when trying to understand certain diseases,” explains Per.
On a par with the 20th century's IT revolution
So, the world is on the brink of a quantum revolution - in fact the second one of its kind. The first quantum revolution took off a century ago and paved the way for the transistor in 1947. Just over ten years later, the laser saw the light of day and soon after that also the atomic clock, which laid the foundation for GPS. Fantastic technical innovations that would fundamentally change society. What was not understood at the time was that quantum mechanics had even more potential. And it’s this power that - when unleashed - will pave the way for a second quantum revolution.
“This is a very exciting development in society. One can compare it with the 20th century's IT revolution and how it affected society. I believe that this quantum revolution will have the same kind of impact on our lives,” says Per.
Welcome to the lecture
The William Chalmers Lecture 2023 is held in Swedish and takes place on 7 November at 18 – 19:30 in Runan, Chalmers Kårhus. Read more about the lecture and register.