British scientists have taken the first steps towards building a real-life version of Deep Thought, the supercomputer programmed to solve the "ultimate question of life, the universe, and everything" in The Hitchhiker's Guide To The Galaxy.

The team has come up with the first practical blueprint for constructing a giant quantum computer, a thinking device capable of rapidly providing answers to problems that would take an ordinary computer billions of years to solve.

A proof-of-concept early prototype is planned within two years at the University of Sussex.

But the ground-breaking modular design could theoretically pave the way to a machine as large as a football field with undreamed of levels of computing power.

While Deep Thought's solution to the meaning of life was "42", the Sussex scientists hope their creation will prove a lot more useful than the supercomputer in Douglas Adams's comic space opera.

Quantum computers, which harness weird effects influencing the nature of reality at the subatomic level, have the potential to unravel the deepest cosmological mysteries, create life-saving medicines, transform weather forecasting, and take encryption to new levels.

Until now, quantum computing has largely been a theoretical concept with enormous potential but little in the way of practical development.

The new design idea, described in the journal Science Advances, is seen as a game changer because it allows connection speeds between individual quantum computing modules 100,000 times faster than any previously envisaged.

Professor Winfried Hensinger, head of the Ion Quantum Technology Group at the University of Sussex, said: "For many years, people said that it was completely impossible to construct an actual quantum computer.

"With our work we have not only shown that it can be done, but now we are delivering a nuts and bolts construction plan to build an actual large-scale machine."

The key to a quantum computer is its ability to operate on the basis of a circuit not only being "on" or "off" but occupying a state that is both "on" and "off" at the same time.

This is in accordance with the laws of quantum mechanics, which allow very small particles to exist in multiple "superposition" states until they are observed or disturbed.

In a similar way, a coin spun in the air cannot be said to occupy a "heads" or "tails" state until it is caught.

While a classical computer has "bits" made up of zeros and ones, a quantum computer has "qubits" which can take on the value of zero or one or both simultaneously.

Previously, scientists proposed using fibre optic connections to link quantum computer modules. The new concept introduces electric field connections that allow charged atoms, or ions, to be transported from one module to another.

Prof Hensinger leads a team that includes US colleagues from Google, Aarhus University in Denmark, the Riken institute in Japan, and Siegen University in Germany.

Prof Hensinger added: "The availability of a universal quantum computer may have a fundamental impact on society as a whole.

"Without doubt it is still challenging to build a large-scale machine, but now is the time to translate academic excellence into actual application building on the UK's strengths in this ground-breaking technology. I am very excited to work with industry and government to make this happen."