Week 10, summary 
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Quantum communication. 

1. Classical Entropy: Entropy, joint entropy, mutual entropy, 
   and various inequalities. Quantum Von-Neumenn's entropy. 

2.  Holevo's bound, 
  showing than $n$ qubits do not carry more 
  than $n$ bit of information. 

3. quantum communication protocols: 
   The complexity is measured by the number of bits required to compute 
a function f on Alice's and Bob's inputs. We show how 
   to convert quantum algorithms (Deutch-jozsa, Grover)  to distributed 
 algorithms  computing Or with provable quadratic improvement, 
and restriced Equality with provable exponential improvement, 
in the case of exact computation.  
We mention Ran Raz's protocol which proves exponential seperation 
  between quantum and classical communication complexity, 
  in the promise problem model, without the requirement that computation 
is exact.