Quantum robots were first investigated in the late 1990s by Paul Benioff, a remarkably original thinker at Argonne National Laboratory in Illinois.
Benioff is currently occupied in holding a candle for a theory of everything based on quantum numbers (more or less single handedly).
So a team of Chinese physicists led by Daoyi Dong at the University of Science and Technology of China in Hefei , China, has taken up the challenge to develop our ideas about quantum robotics a little further.
Benioff’s work explored the way in which a quantum robot might explore a 2D or 3D space using the laws of quantum mechanics to speed up the search. If memory serves, there is a decent speed up in two dimensions but not in three (which has interesting implications for molecular building machines). But he gave no thought to the internal structure of his robots or how they might be constructed.
The Chinese team have now given form to this structure. Quantum robots, they say, will consist of three parts:
i. an information processor consisting of one or several quantum computers
ii. some kind of quantum actuator that interacts with the environment to carry out a task
iii. a quantum sensor which monitors the environment, such as a SQUID (superconducting quantum interference device) which detects magnetic fields.
The team has mysteriously omitted a quantum communication module to send and receive data from their classical masters.
So what can a quantum robot do that, say, a classical robot attached to quantum sensors cannot?
That’s not entirely clear. Daoyi and co say that most planning and control problems in robotics can be posed as search problems. So Grover’s search algorithm gives a significant speed up in the time it takes to solve these problems. But presumably the same would be true of a classical robot controlled by a quantum computer.
Where they might prosper is in size. Presumably quantum robots will operate at a scale that is not accessible to classical robots. And this raises the prospect of a world beneath our own populated by quantum machines operating on entirely different principles to ours. All this needs some fleshing out.
The China team’s vision is far more sanguine, having dreamt up the following predictable applications. They say:
“Quantum robots have many potentially important applications in military affairs, national defense, aviation and spaceflight, biomedicine, scientific research, safety engineering and other daily life tasks.”
(It must have taken them weeks to think up that list.)
Now all they have to do is build one of these guys.
Ref: arxiv.org/abs/0810.3283: Quantum robot: structure, algorithms and applications