Doxa: July 2024

Wednesday, July 3, 2024

The Deutsch-Jozsa algorithm seeks to create an appreciation of how supersposition

results in at-a-glance results in the case of an oracle ie a simple binary function that

outputs 0 or 1. One is trying to see if the function is constant or balanced, outputting

either always the same output be it 0 or 1, or an equal number of each.

Crucial here, is the notion of register: a group of one or more qubits is a register. We

will need two registers, the second having only 1 qubit.

* * *

A constant oracle can be created with a simple two one-qubit registers. If the function

inputs 0, one adds the identity gate to register 2. If it inputs 1, one adds aan X gate.

We're seeing 0 in the second register in all cases.

For a balanced output, ta CNOT gate with the last qubit as target will work:

For example:

The fully elaborated model for a balanced outcome:

Trying to get clear on the Hadamard:

* * *

Getting ready to get trough Sarma 13, the Deutsch-Jozsa algorithm, tomorrow.

It was first defined in 1992 to illustrate that quantum superiority is possibe.