Linear Algebra
Underneath everything, quantum computing is linear algebra. Gates as matrices, states as vectors, and the tensor product behind the exponential count.
Posts
-
13:47 Quantum Computing The tensor product: why 10 qubits means 1024 numbers
One humble operation builds the space that every multi-qubit state lives in, and explains the exponential. Two qubits in, four amplitudes out.
-
12:45 Quantum Computing Quantum gates are just matrices you can run by hand
X, H, Z and the rotations: applying a gate is multiplying a matrix by a vector. Literally. Worked by hand, then checked in Qiskit.
-
09:38 Milestones Three quantum ways to diagonalize a giant matrix
A surprising number of hard problems are one eigenvalue problem on a matrix too big to build. Variational, Krylov, sample based, compared