.. title: Quantum Class 10, Thu 2022-09-29
.. slug: class10
.. date: 2022-09-29
.. tags: class
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.. contents:: Table of contents
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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/Chong-QC-UCLA19.pdf
They lead to https://nwquantum.com/events/
`NQN Seminar Series – Hybrid Classical-Quantum Algorithms `_.
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.
#. `Phase Kickback V Abhijith Rao `_
#. `Qiskit Phase Kickback `_
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/ch-algorithms/deutsch-jozsa.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.
Bernstein-Vazirani Algorithm
============================
This would be that next step.
https://qiskit.org/textbook/ch-algorithms/bernstein-vazirani.html
Simon's periodicity
===================
Blackbox $F: \\{0,1\\}^n \\to \\{0,1\\}^n$
For some unknown $c$, $F(x\\oplus c) = F(x)$.
Determine $c$.