Interactive Notes · Quantum Computing · 2026

From Zero to
Quantum Computing

Self-contained interactive notes covering linear algebra, quantum mechanics, entanglement and quantum circuits — with live visualizations, exercises and a circuit simulator.

8 notes · 60+ sections Circuit sandbox
Section 01

The Notes

Note 01 · Linear Algebra for Quantum

Linear Algebra for Quantum

Vectors, complex numbers, inner products, Dirac notation, matrices and eigenvalues — everything needed to understand qubits from scratch.

10 sections
Note 02 · Basic Concepts of Quantum Computing

Basic Concepts of Quantum Computing

Introduction to the fundamental ideas of quantum mechanics and quantum computing, with a focus on the postulates of quantum mechanics, the qubit, measurement, and quantum gates.

10 sections
Note 03 · Composite Quantum Systems

Composite Quantum Systems

How to describe joint quantum systems? Introduction to the tensor product, computing basis states of composite systems, and visualizing two-qubit states.

6 sections
Note 04 · Quantum Circuits

Quantum Circuits

Introduction to quantum circuits, the standard model of quantum computation. How to represent quantum algorithms as sequences of gates, and how to visualize them with the circuit diagram notation.

9 sections
Note 05 · Quantum Fourier Transform

Quantum Fourier Transform

From the classical Discrete Fourier Transform to its quantum analogue: how the QFT maps amplitudes, how to implement it with H and controlled-phase gates, and why it is exponentially faster than the FFT.

6 sections
Note 06 · Shor's Algorithm

Shor's Algorithm

From the first quantum algorithm ever — Deutsch's — to Shor's factoring algorithm that can break RSA encryption. Covers quantum parallelism, period finding, the Quantum Fourier Transform, and the exponential speedup over classical computers.

9 sections
Note 07 · Quantum Communications

Quantum Communications

Quantum Key Distribution, the BB84 protocol, eavesdropper detection, post-processing and privacy amplification — how quantum mechanics makes cryptography unconditionally secure.

5 sections
Note 08 · Quantum Error Correction

Quantum Error Correction

Classical vs quantum error correction, the quantum repetition code, stabilizer formalism, syndrome extraction — how to protect quantum information without ever measuring it directly.

5 sections
Interactive Lab

⚛ Circuit Sandbox

Drag-and-drop quantum circuit editor — up to 4 qubits, 8 moments. Live probability outcomes, preset circuits, Bloch sphere display.

Launch Sandbox ↗
Section 02

Key Concepts Index

Vectors Note 01 · §1 Space and Norm Note 01 · §2 Complex Numbers Note 01 · §3 Inner Product Note 01 · §4 Dirac Notation Note 01 · §5 Why |0⟩=(1,0)? Note 01 · §6 The Qubit Note 01 · §7 Measurement Note 01 · §8 Matrices & Gates Note 01 · §9 Eigenvalues Note 01 · §10 QM Postulates Note 02 · §1 Pauli Matrices Note 02 · §1b Measurement Bases Note 02 · §1c The Qubit Note 02 · §2 Measuring a Qubit Note 02 · §3 Transforming a Qubit Note 02 · §4 Quantum Gates Note 02 · §5 Basis Change Note 02 · §6 Measurement in Arbitrary Basis Note 02 · §7 Tricks & Summary Note 02 · §8 Composite Systems Note 03 · §1 Two-Qubit States Note 03 · §2 Entangled States Note 03 · §3 CHSH Game Note 03 · §4 Multi-Qubit Gates Note 03 · §5 Mixed States Note 03 · §6 Quantum Computing Note 04 · §1 Boolean Functions Note 04 · §2 Quantum Parallelism Note 04 · §3 State Transformation Note 04 · §4 Generating α|0⟩+β|1⟩ Note 04 · §5 No-Cloning Theorem Note 04 · §6 Bell Basis Measurement Note 04 · §7 Quantum Teleportation Note 04 · §8 Quantum Tomography Note 04 · §9 Classical DFT Note 05 · §1 Quantum Variant Note 05 · §2 QFT on Basis States Note 05 · §3 N=4 Circuit (2 qubits) Note 05 · §4 N=8 Circuit (3 qubits) Note 05 · §5 Complexity Note 05 · §6 Deutsch's Algorithm Note 06 · §1 Factorization = Order Finding Note 06 · §2 Order Finding = Period Finding Note 06 · §3 Period Finding with FT Note 06 · §4 Classical Period Finding Note 06 · §5 Order Finding with QFT (Shor) Note 06 · §6 QFT of First Register Note 06 · §7 Complexity Analysis Note 06 · §8 Full Example: Factor 15 Note 06 · §9 Why QKD? Note 07 · §1 BB84 Protocol Note 07 · §2 Eavesdropper Detection Note 07 · §3 BB84 Analysis Note 07 · §4 Post-Processing Note 07 · §5 Classical Error Correction Note 08 · §1 QEC Challenges Note 08 · §2 Quantum Repetition Code Note 08 · §3 Stabilizer Formalism Note 08 · §4 Syndrome Extraction Note 08 · §5
Section 03

How to Use These Notes

1

Start with Note 01 if you are new to linear algebra. Otherwise jump directly to any section from the sidebar.

2

Read the theory boxes, then work through the exercises. Hints are hidden — always try first!

3

Use the interactive canvases to build intuition — click, drag and adjust sliders.

4

Open the Circuit Sandbox to experiment freely with quantum gates and see live probability outcomes.

No prerequisites. Each note starts from absolute basics. All maths is introduced step-by-step with worked examples and interactive visualizations.