This eve I clicked a few things, pieced together a simple quantum computing circuit and ran it on a quantum computer – an actual quantum computer(!), IBM Quantum’s ibm_nairobi.
Here’s the circuit, the Deutsch algorithm with \(U_{f_2}\) slotted in as the function to test. Pretend you can’t see what function it is – the result of the algorithm will tell us (something about) which it is.
In hindsight, I could have simplified it…
Wait a bit…
Then finally, a result!
The zeroth bit (least significant bit) is (almost always) zero, so the function is balanced.