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IS NOKIA destined to dominate the mobile phone industry? Clues to questions
like this may lie in the behaviour of ultra-cold gases.

Networks such as business markets are mathematically identical to gases of
certain atoms, says Albert-Laszlo Barabasi from the University of Notre Dame in
Indiana. So the quantum behaviour of these gases could help explain the
emergence of industrial monopolies.

When cooled to near absolute zero, atoms such as rubidium crowd into the
single lowest-energy quantum state, a process called Bose-Einstein condensation.
Barabasi and his colleague Ginestra Bianconi say that this is analogous to a
single node dominating a network, when it captures most of the links that
usually join a host of nodes together. If the nodes represent businesses and the
links their sales, the winning node could be a firm with a monopoly.

The researchers generated networks on a computer, adding nodes and giving
each a random 鈥渇itness鈥� score. Each new node extended links to the others,
trying to connect with the fitter ones. The researchers then applied a
鈥渢emperature鈥� to the network to adjust the spread of fitness among the nodes. At
high temperatures鈥攚hich level out the scores鈥攖he fitter nodes get
more links, but no single node dominates. As the temperature drops and the
scores widen, the fitter nodes gather more and more links. Eventually a single
node will suddenly grab a sizeable fraction of the links鈥攁nalogous to the
collapse of the cold gas鈥攁nd emerge the clear winner.

A real network such as a business market has a fitness distribution that is
very hard to manipulate, Barabasi says, so the challenge is to find out what
that distribution is and decide whether it predisposes the network to have a
dominant node or not.