Quantum Information in a Distributed Apparatus
  We investigate the information provided about a specified distributed apparatus of n units in the measurement of a quantum state. It is shown that, in contrast to such measurement of a classical state, which is bounded by log (n+1) bits, the information in a quantum measurement is bounded by 3.7 x n^(1/2) bits. This means that the use of quantum apparatus offers an exponential advantage over classical apparatus. 
Subhash Kak