Unlearn Everything.
Then Learn Quantum.
Reality is weirder than you think. Quantum mechanics breaks every rule you know— and it's the real physics running the universe. Ready to see how deep the rabbit hole goes?
Welcome to Quantum Weirdness
Everything you think you know about reality is about to change
Measurement Creates Reality
A quantum particle literally doesn't have a position until you look at it. No philosophy—just physics.
Superposition ≠ Uncertainty
A qubit isn't secretly 0 or 1. It's genuinely BOTH. This isn't ignorance—it's nature's actual behavior.
Spooky Action at a Distance
Two particles can be so connected that measuring one instantly affects the other—even across the universe.
No Classical Analogy Works
Forget everything. Classical physics is just a special case. Quantum is the real deal, and it's bizarre.
Learning Path
Progress from quantum foundations to advanced algorithms
Mental Model Reset
Wave-Particle Duality
The double-slit experiment reveals quantum reality
Destroy Your Assumptions
What you MUST unlearn before starting
Why a Qubit is NOT a Faster Bit
The fundamental difference that changes everything
Measurement Creates Reality
Why observation is a physical interaction
Qubits & The Bloch Sphere
Quantum Algorithms
Deutsch-Jozsa Algorithm
Toy problem showing quantum speedup exists (exponential advantage for specific oracle problems)
Grover's Search
Quadratic speedup for unstructured search—practical for database lookups and optimization
Shor's Algorithm
Breaks RSA encryption—why governments are racing to build quantum computers NOW
Advanced Topics
Coming SoonReady to Break Your Brain? 🤯
Start by seeing quantum reality through the double-slit experiment. Then we'll destroy your classical assumptions.
Begin: Wave-Particle Duality 🌿 Quantum in NatureWhy Does Quantum Computing Matter?
Quantum mechanics isn't just theoretical physics—it's already powering real-world breakthroughs:
Drug Discovery & Chemistry
Simulating molecular interactions that are impossible for classical computers. Quantum computers can model protein folding and chemical reactions at the atomic level.
Cryptography
Shor's algorithm can break RSA encryption. Post-quantum cryptography is being developed right now to secure future communications.
Optimization Problems
Supply chain logistics, financial modeling, traffic routing—problems with exponentially large solution spaces that classical algorithms struggle with.
Machine Learning
Quantum machine learning algorithms can process high-dimensional data in ways classical neural networks cannot.
About QbitsOnly
QbitsOnly is a free, open-source quantum computing education platform that destroys classical assumptions and rebuilds quantum intuition from scratch.
Created by Sushant Mamgain
A quantum computing enthusiast passionate about making complex quantum concepts accessible to everyone. This platform was born from a belief that quantum computing education should be free, practical, and focused on deep understanding rather than surface-level explanations.
✅ Success Criteria: Are You Ready to Move Forward?
Here's how to know you've truly mastered each phase—not just read the content, but can actually USE quantum computing concepts.
Phase 0: Mental Model Reset
You've completed Phase 0 when you can:
- ✓ Explain why a qubit is not a faster bit (without using the word "superposition" as magic)
- ✓ Describe why measurement destroys quantum information (and why this matters for QA/debugging)
- ✓ Understand that quantum probability is fundamentally different from classical randomness
- ✓ Recognize when someone is misusing quantum terms (e.g., "quantum AI" marketing BS)
Can you explain to a friend why quantum computers aren't just "faster at searching"? If yes, you're ready for Phase 1.
Phase 1: Qubits & Gates
You've completed Phase 1 when you can:
- ✓ Visualize any single-qubit state on the Bloch sphere (given angles θ and φ)
- ✓ Describe what the H, X, Z, Y gates do (as rotations, not just "flip" or "phase")
- ✓ Implement a Bell state (entangled pair) from scratch in Qiskit
- ✓ Explain why entanglement is not "spooky action at a distance" (no faster-than-light communication)
- ✓ Know when to use CNOT vs CZ vs SWAP gates
Build a 2-qubit circuit that creates superposition + entanglement, then measure. Run it on IBM Quantum. If you can predict the measurement probabilities, you're ready for Phase 2.
Phase 2: Quantum Algorithms
You've completed Phase 2 when you can:
- ✓ Implement Deutsch-Jozsa for n=3 qubits with a custom oracle
- ✓ Explain how Grover's algorithm amplifies target states (without hand-waving "quantum magic")
- ✓ Calculate the optimal number of Grover iterations for a given search space size
- ✓ Describe why Shor's algorithm threatens RSA (period finding → factoring)
- ✓ Know when to use classical vs quantum approaches (e.g., why sorted data doesn't need Grover's)
- ✓ Build a simple oracle for Grover's search that finds a specific 3-bit string
Pick a real-world problem (e.g., database search, optimization). Can you determine whether Deutsch-Jozsa, Grover's, or Shor's applies (or if classical is better)? If yes, you've mastered Phase 2.
🎓 What's Next After Phase 2?
Future phases will cover advanced topics: Quantum Error Correction, Variational Algorithms (VQE/QAOA), Quantum Machine Learning, and real-world implementations.
You're ready when:
✓ You can build circuits, not just read about them
✓ You know when quantum helps vs when classical is better
✓ You understand the math isn't magic—it's rotations + interference
Pro Tip: Don't rush! Most people take 2-3 months to truly master Phase 1 & 2. Build projects, break circuits, ask "why" constantly. That's how you actually learn quantum computing.