1 Quantum jokes

of varying quality... https://upjoke.com/quantum-jokes

2 Final project presentations

1. Everyone who requested a specific date, got it. I assigned the others to even out the calendar.

2. Do any of the Dec 1 people want to move to Dec 5? The first two who email me can do that.

3. Other changes that don't overload particular days might be ok.

4. No matter when you talk, you have until Fri Dec 9 to submit your project.

3 Final project presentations

1. Everyone who requested a specific date, got it. I assigned the others to even out the calendar.

2. Do any of the Dec 1 people want to move to Dec 5? The first two who email me can do that.

3. Other changes that don't overload particular days might be ok.

4. No matter when you talk, you have until Fri Dec 9 to submit your project.

5. Updated list is on class 22.

4 Jochen Rao on Molecules

1. This fits together with the variational quantum eigensolver talk.

2. 22.Molecules 9:50 Dec 11, 2020

5 Measurement-based computation, aka One way quantum computation

This is an alternative to the quantum logic gate model that uses reversible unitary gates in a quantum circuit.

Since performing a measurement changes the measured qbits, use it.

1. https://www.quantiki.org/wiki/one-way-computation :

   "One way quantum computation (1WQC) uses an initially highly entangled state (called a cluster state), and then a pattern of single qubit measurements along different directions, together with feed-forward based on the results, in order to drive a quantum computation. The final result of the computation is obtained by measuring the last remaining qubits in the computational basis..."

2. https://en.wikipedia.org/wiki/One-way_quantum_computer

   1. This is a one-way computer.

   2. Operations:

      1. Supplement the input/output qbits with some auxillary qbits.

      2. Entangle some of them.

      3. Measure some of the auxillary qbits wrt some bases. This affects the output qbits since they are entangled.

      4. Depending on the measurement results, perform further operations on the output qbits. These are called corrections.

   3. Repeat.

3. This has equivalent formal power to reversible gates.

4. It may be better suited to certain HW.

5. One-way Quantum Computation - a tutorial introduction Dan E. Browne, Hans J. Briegel.

6. How the excellent Jochen Rau presents it:

   14. Measurement-based computation 36:44. Nov 27, 2020

7. So now you've seen 3 models of quantum computation.

6 MaxCut

https://en.wikipedia.org/wiki/Maximum_cut

Rao again, since he's excellent.

21.Classical optimization: MaxCut problem 14:47