Quantum computing is a concept which is still being pursued as one that can be commercially exploited. It is based upon the thought experiment of Schrödinger’s cat. Or perhaps it is better to say that Schrödinger’s cat illustrates the concept of “quantum superposition”.
In this almost unintelligible thought experiment a cat is placed inside a sealed box with radioactive material and a poison. A monitor inside the box detects radioactivity and the flask containing the poison is shattered killing the cat. An interpretation called the “Copenhagen interpretation of quantum mechanics” implies that the cat is simultaneously dead and alive. In observing the cat, it is either dead or alive and cannot be dead alive at the same time. As I understand it, “quantum superposition” is illustrated in the way that the cat is both dead and alive at the same time but this state of affairs collapses into reality at a point when the cat is alive or dead.
A Cambridge start-up – a small business with aspirations to be a large successful one and into which investors pour money in the expectation that they become rich – is pushing forward with quantum computers. Steve Brierley is the founder of a business called Riverlane. He is an expert on Schrödinger’s cat! I’m glad someone understands it. He wants to make the concept of quantum mechanics useful and is an optimist and a pragmatist. His colleagues say there is no future in quantum computing but he disagrees.
In brief, standard computing relies on “bits” that are either on or off, 1 or 0. This form of computing is limited to binary decisions. Everything is broken down into this on and off form of processing. Quantum computers use qubits. This form of computing is based upon the premise that bits can be on and off, 1 and 0, at the same time. In other words the computing equivalent of Schrödinger’s cat being dead and alive at the same time. It seems to be physically impossible.
The objective when achieved is much faster computing. In 2019 Google apparently claimed to have achieved supremacy in the world of quantum computing. Their rivals, IBM, disputed it.
Some experts believe that it is almost impossible to build the hardware to run a quantum computer and therefore it could never be exploited commercially. With this in mind Mr Brierley thought he might be developing a program that would never exist. Perhaps it existed in his mind, a thought experiment, and no more!
Commercially exploiting quantum computers appears to be very difficult. One problem is that you have to design a bespoke operating system for each computer. Brearley developed their own operating system called Deltaflow. It is apparently similar to the old DOS operating system that we had in PCs in the 1980s.
At the beginning
Brierley believes that quantum computers are a bit like the early digital cameras were: pretty poor compared to film cameras at that time. And currently quantum computers are not as good as standard laptops. But we can see how digital cameras developed and evolved into the fantastic devices that they are today. You have more computing power in a smart phone then you did on Apollo 13, far more. And digital cameras in smart phones are far superior to the old digital cameras.
Brierley regards quantum computers as “chemistry on steroids”. He hopes to make an impact on the computer industry within about five years. And he also hopes that these computers will be able to solve problems that would otherwise never be solved. Schrödinger’s cat is in the news again and will continue to be so for the foreseeable future.
My thanks to James Hurley of The Times 7 Sept 2020.