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PAR Class 23, Thurs 2020-04-16

1   Final projects

1.1   Presentations

  1. Mon April 20
    1. Sava C & Davi P & Emil V
  2. Thurs April 23
    1. Kevi M
    2. Liz C
    3. Chri H
    4. Zhep L
  3. Mon April 27
    1. Joe C & Alex Z
    2. Mike M
    3. Matt R & Skyl S
    4. Eliz C
    5. John F & Hayl R & Mish S
    6. Ross D
    7. Clar S & Garr D

1.2   Reports

Due last class day, Wed April 29.

See syllabus.

To the 2 students in the grad version: do more work.

2   Quantum computing ctd

2.1   Grover's algorithm etc

  1. Algorithms:
    1. Some, but not all, are faster.
    2. Bounded-error quantum polynomial time (BQP)
      1. "is the class of decision problems solvable by a quantum computer in polynomial time, with an error probability of at most 1/3 for all instances" - https://en.wikipedia.org/wiki/BQP
      2. Includes integer factorization and discrete log.
      3. Relation to NP is unknown (big unsolved problem).
    3. Grover's algorithm:
      1. https://en.wikipedia.org/wiki/Grover%27s_algorithm
      2. Given a black box with N inputs and 1 output.
      3. Exactly one input makes the output 1.
      4. Problem: which one?
      5. Classical solution: Try each input, T=N.
      6. Quantum: $T=\sqrt(N)$.
      7. Probabilistic.
      8. Apps: mean, median, reverse a crypto hash, find collisions, generate false blocks.
      9. Can extend to quantum partial search.
      10. Grover's algorithm is optimal.
      11. This suggests that NP is not in BQP .