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A Hopfield net
is composed of binary threshold units with
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recurrent
connections between them. Recurrent
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networks of
non-linear units are generally very hard to
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analyze. They
can behave in many different ways:
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Settle
to a stable state
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Oscillate
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Follow
chaotic trajectories that cannot be predicted
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far
into the future.
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But Hopfield
realized that if the connections are
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symmetric, there
is a global energy function
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Each
“configuration” of the network has an energy.
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The
binary threshold decision rule causes the network
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to
settle to an energy minimum.
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