QAOA: The Quantum Approximate Optimization Algorithm
How QAOA works: alternating cost and mixer operators, a classical optimizer in the loop, and applications to logistics, finance and energy.
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Quantum Phase Estimation (QPE) Step by Step
Quantum phase estimation step by step: controlled unitaries, the inverse QFT, precision, error sources and its use in Shor’s algorithm and chemistry.
Quantum Fourier Transform (QFT): What It Does
The quantum Fourier transform explained: its circuit, its role in phase estimation and Shor’s algorithm, and how it differs from the classical FFT.
Grover’s Algorithm: Quantum Search, Explained
How Grover’s algorithm searches an unsorted list in about √N steps using an oracle and amplitude amplification, and its effect on cryptography.
Shor’s Algorithm: How Quantum Factoring Works
How Shor’s algorithm factors integers: period finding, modular exponentiation, the quantum Fourier transform and the circuit it needs.
Quantum Computing for Beginners: Start Here
A starting point for beginners: the quantum physics behind quantum computing, including duality, superposition, entanglement and uncertainty.
Quantum AI Stocks: What Investors Should Check
What to check before buying quantum AI stocks: who the companies are, market trends, risks, regulation and how to judge growth forecasts.
Quantum AI: What It Means and What It Does Not
What quantum AI means: quantum machine learning and quantum neural networks, the hardware and software involved, and claims that go too far.
Who Invented Quantum Physics? The People and Dates
Who created quantum physics: Planck, Einstein, Bohr, Heisenberg, Schrödinger, Dirac, Pauli, de Broglie, Born and others, with their key ideas.
How Do Quantum Computers Work?
How quantum computers work: qubits, superposition, interference, entanglement, gates and circuits, algorithms, and the problem of decoherence.
Are Quantum Computers Faster Than Classical Ones?
When quantum computers are faster than classical ones and when they are not, with Shor’s and Grover’s algorithms as worked examples.
Is Quantum Physics Real? What the Evidence Shows
The experimental evidence for quantum physics, from the double slit and Bell tests to tunneling and the technologies built on quantum effects.