Quantum Zeno effect  From Wikipedia, the free encyclopedia Jump
to: navigation, search  The quantum Zeno effect is a situation
in which an unstable particle, if observed continuously, will
never decay.[1] The term was coined by George Sudarshan and
Baidyanath Misra of the University of Texas in 1977. One can
"freeze" the evolution of the system by measuring it frequently
enough in its (known) initial state. The meaning of the term has
since expanded, leading to a more technical definition in which
time evolution can be suppressed not only by measurement: the
quantum Zeno effect is the suppression of unitary time evolution
caused by quantum decoherence in quantum systems provided by a
variety of sources: measurement, interactions with the
environment, stochastic fields, and so on.[2] As an outgrowth of
study of the quantum Zeno effect, it has become clear that
applying a series of sufficiently strong and fast pulses with
appropriate symmetry can also decouple a system from its
decohering environment.[3]  The n