Quantum Computing

Measuring Qubits

Having settled on an understanding of qubits and quantum states, we’re ready for the next step in our journey. To get anything useful out of qubits, we control them with quantum gates, the quantum equivalent of classical gates.

To get a feel for quantum programs steering quantum states to the correct solution, imagine a magic trick where your selected card appears at the top of the deck. It may look random, but the shuffling of the deck is actually a controlled reordering of the cards to force the selected card to the top of the deck. Likewise, even though the quantum bits collapse randomly to one of the two idealized states, the quantum program applies the quantum gates in a way that forces the qubits to collapse to the desired ...