Quantum Class 10, Thu 20220929
1 IEEE Quantum Week 2022
This conference was last week. It was expensive but you can get something for free thus. Look at https://qce.quantum.ieee.org/2022/home/program/keynotes/
to see current important topics. Then google the speakers and titles to look for free versions of their presentations.
You could also pay for virtual access for 3 months.
E.g. Fred Chong: Closing the Gap Between Quantum Algorithms and Hardware.
https://www.youtube.com/watch?v=VNX4RLtbFeA
https://people.cs.uchicago.edu/~ftchong/ChongQCUCLA19.pdf
They lead to https://nwquantum.com/events/
2 Quantum properties  Phase
You cannot measure the phase of qbit.
You can measure the relative phase of 2 qbits.
Many algorithms encode the answer as a phase shift of a qbit.
Phase kickback means that a gate that runs one way, e.g., the control bit affects an output bit, can be made to run the other way, e.g., the control bit is changed, by making the other bit a Hadamad basis.
3 Deutsch Jozsa Algorithm, ctd
The problem is artificial and uninteresting by itself. Its importance is that it was the first problem with a faster quantum algorithm (than its classical algorithm). It's a proof of principle.
 This is a nice detailed description:

https://en.wikipedia.org/wiki/Deutsch%E2%80%93Jozsa_algorithm
We're following: https://qiskit.org/textbook/chalgorithms/deutschjozsa.html
Another view: Deutsch Jozsa Algorithm  Quantum Computer Programming w/ Qiskit p.3.
Then the next step is to find a more interesting problem that can be sped up.
4 BernsteinVazirani Algorithm
This would be that next step.
https://qiskit.org/textbook/chalgorithms/bernsteinvazirani.html
5 Simon's periodicity
Blackbox $F: \{0,1\}^n \to \{0,1\}^n$
For some unknown $c$, $F(x\oplus c) = F(x)$.
Determine $c$.