Making use of the famous Schrödinger’s cat, Arjen presents to us the concepts of normalization and quantum probabilities, and how together they can help us understand the Born Rule. The Born Rule is a mathematical trick that helps us know how likely the possible outcomes are when we measure a qubit.  This is a widely used trick for any study of the mathematics of a  quantum measurement.

Main Takeaways

• Any single-qubit quantum state can be written as α|0⟩+β|1⟩, where the coefficients are complex numbers.
• The Born Rule states that the probability of measuring |0⟩(|1⟩) is the absolute value of α(β) squared.
• The sum of the absolute values of α and β squared needs to equal 1 for the quantum state to be normalized.