An orchestra plays inside a giant refrigerator. The musicians are qubits, the elementary cells of a quantum computer. To play in harmony, they need silence: thermal noise drowns out the melody. That's why the heart of a quantum processor is cooled to nearly absolute zero — minus 273 degrees Celsius.
But the music must be brought out to the audience. The wires running from the cold into the warm room are like long corridors where sound gets distorted and fades. Each cable carries heat inward and destroys the delicate quantum state. The authors remind us: today's quantum processors have already proven their usefulness, but without solving the signal transmission problem, you can't assemble a big orchestra.
The solution is not just to insulate the 'windows' but to move part of the electronics right into the cold. Tiny amplifiers operating at the same minus 273 could pick up a weak signal and send it onward, already strengthened. Another path is to learn to compress information: instead of a hundred wires, run a single one, but such that the entire 'concert' travels along it at once, without confusion.
The circle closes: if the orchestra learns to play so that it can be heard beyond the refrigerator walls, quantum computers will cease to be a laboratory curiosity. They will be able to solve problems that today are beyond the combined power of all the world's supercomputers.
The temperature inside a superconducting quantum processor is hundreds of times colder than outer space — even far from stars, it's still 'warm' there: about minus 270 degrees.
In Peter Watts's novel 'Blindsight', an alien ship uses quantum computing at ultra-low temperatures, and the protagonists must work in conditions where a thought can be destroyed by a single clumsy movement.