Experimental Quantum Physics Lab

Quantum
Codex

Where Physics Becomes Interactive Thought.
Explore quantum wavefunctions, tunnelling, orbitals, and uncertainty states.

Learn Quantum
Mechanics

An interactive journey from classical crisis to quantum reality. Each lesson builds on the last, guiding you from intuition to formalism.

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Quantum Roadmap
See how every concept connects as an interactive knowledge graph.
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Computational Physics
as a living medium

Physics equations live on paper. Quantum Codex makes them inhabitable.

This is an evolving experimental project — a personal lab notebook rendered interactive. Each simulation is built from mathematical first principles, not borrowed libraries or pre-baked demos.

The goal is simple: to let curious minds encounter physics as something you can touch, rotate, break, and rebuild — not just read about.

3D / 2D WebGL & Canvas Engine
5 Interactive Quantum Labs
100% Mathematical Fidelity
60 FPS Native GPU Performance

Quantum Roadmap

Every concept in quantum mechanics connects to others. Click any node to jump to that lesson.

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Quantum Mechanics · Lesson 03

The Bohr Model

In 1913, a young Danish physicist proposed something radical: electrons can only exist at specific, quantized distances from the nucleus — and nothing in between.

14 min read
Foundational

What You'll Learn

The Bohr Model was a pivotal step in the development of quantum mechanics. It introduced the idea that electrons occupy discrete energy levels and that transitions between these levels produce or absorb specific wavelengths of light.

Prerequisite Wave-Particle Duality
Duration 14 min read
Simulation 3D Bohr Model Lab
Difficulty Foundational

A Crisis in Classical Physics

By 1900, classical physics had hit a wall. The prevailing model of the atom — Thomson's "plum pudding" — and later Rutherford's nuclear model could not explain why atoms emit light in discrete spectral lines instead of a continuous rainbow.

1897
Discovery of the Electron

J.J. Thomson discovers the electron, shattering the idea of the indivisible atom.

1911
Rutherford's Nuclear Model

Ernest Rutherford proves the atom has a dense positive nucleus. But why don't electrons spiral inward?

1913
Bohr Postulates Quantized Orbits

Niels Bohr proposes that electrons occupy fixed, quantized orbits and emit photons when jumping between them.

Quantized Energy Levels

Bohr's radical postulate was that electrons don't just orbit anywhere — they can only exist in specific, allowed orbits. Each orbit corresponds to a discrete energy level, labelled by the principal quantum number n.

💡

The key insight: Between orbits, there is no in-between. An electron does not smoothly drift from one level to another — it makes an instantaneous quantum leap.

When an electron falls from a higher orbit (n=2) to a lower one (n=1), the energy difference is released as a photon with a precise wavelength. This is why hydrogen emits specific spectral lines, not a smeared spectrum.

The energy of orbit n in hydrogen is given by Eₙ = −13.6 eV / n². Higher n means higher (less negative) energy. The ground state (n=1) at −13.6 eV is the most tightly bound configuration.

Explore the Energy Levels

Adjust the principal quantum number n and atomic number Z to see how the orbital radius and energy change — live, with the electron orbit and energy ladder updating as you drag.

Bohr Energy Calculator

The Energy Formula

Bohr Energy Levels
\(Z\) = atomic number  ·  \(n\) = principal quantum number \((1, 2, 3\ldots)\)

The negative sign indicates a bound state — energy must be added to remove the electron. As \(n\) increases, the electron is farther from the nucleus and less tightly bound.

What People Often Get Wrong

⚠️

Misconception: Electrons physically travel between orbits during a quantum leap.

Reality: There is no trajectory. The electron simply “is” in one state, then “is” in another. There is no in-between path to describe.

⚠️

Misconception: The Bohr Model is correct quantum mechanics.

Reality: It is a historical approximation. It fails for multi-electron atoms and cannot predict spectral fine structure. The Schrödinger equation supersedes it.

Where This Matters

🔬

Spectroscopy: Every element emits a unique spectral fingerprint. Astronomers use the Bohr Model’s predictions to identify elements in distant stars.

💡

Lasers: The population inversion mechanism exploits electron transitions between discrete energy levels — a direct consequence of quantized orbits.

See It In 3D

Now that you understand the theory, explore the Bohr atom in a fully interactive 3D simulation. Adjust electron shells, atomic number, and rotation speed.

Open Simulation
3D Bohr Model Lab
Rotate the atom, change quantum numbers, and watch electron transitions happen in real time.
✦ Key Takeaways
  • Electrons in an atom can only occupy specific, quantized energy levels — there is no continuum.
  • The principal quantum number n determines the energy and radius of each orbit.
  • When an electron transitions between levels, it emits or absorbs a photon with exactly the right energy to bridge the gap.
  • The Bohr Model correctly predicts hydrogen’s spectral lines but is a stepping stone to the full quantum mechanical picture.

Design System Showcase

A comprehensive overview of the Quantum Codex component library.

Content Cards

Information Card

Used for general scientific facts or contextual information.

Wavefunction (ψ)

A mathematical description of the quantum state of an isolated quantum system.

Core Concept

Focuses the user's attention on the fundamental principle of the lesson.

Key Insight

Highlights a profound realization or mathematical consequence.

Key Takeaway

The user should remember this specific point before proceeding.

Common Misconception

Electrons do not orbit the nucleus like planets around a star.

Historical Timeline

1913

Bohr Model Proposed

Niels Bohr proposes that electrons travel in quantized orbits.

1926

Schrödinger Equation

Erwin Schrödinger formulates wave mechanics.

Interactive Components

Interactive Demonstration Container

Schrödinger Solver

Solve 1D potentials numerically.

iℏ ∂ψ/∂t = Ĥψ
Quantum Codex / Simulations / Bohr Model

Bohr Model

Interactive 3D simulation of Niels Bohr's atomic model. Electrons orbit the nucleus in quantised shells — each shell at radius r₀ · n². Hover over orbits for quantum data. Scroll to zoom. Drag to rotate.

Quantum Mechanics WebGL · Three.js
Bohr Model · n = 1–5
— fps

Theory coming soon…

Theoretical derivations, formulas, and educational explanations will be added in a future update.

Quantum Codex / Simulations / Schrödinger Orbital

Schrödinger Orbital

3D probability density clouds of hydrogen-like atomic orbitals computed from Laguerre polynomials and spherical harmonics using Monte Carlo sampling.

Wave Mechanics WebGL · Three.js
Orbital: 2p (m=0)
— fps
Ready

Theory coming soon…

Theoretical derivations, formulas, and educational explanations will be added in a future update.

Quantum Codex / Simulations / Schrödinger Solver

Schrödinger Solver

1D Finite Difference Eigensolver & Wavefunction Visualizer. Computes exact discrete Hamiltonian matrix eigenvalues and eigenstate amplitudes for particle in a box.

1D Eigensolver Canvas 2D · Native JS

Theory coming soon…

Theoretical derivations, formulas, and educational explanations will be added in a future update.

Quantum Codex / Simulations / Quantum Tunnelling

Quantum Tunnelling

Static bound state penetration & dynamic wavepacket reflection/transmission through potential barriers.

Barrier Penetration Canvas 2D · Native JS

Theory coming soon…

Theoretical derivations, formulas, and educational explanations will be added in a future update.

Quantum Codex / Simulations / Heisenberg Principle

Heisenberg Principle Simulation

Visualise trade-offs between position and velocity precision with spectral expansion and live stats overlay.

Uncertainty Principle Canvas 2D · Native JS

Theory coming soon…

Theoretical derivations, formulas, and educational explanations will be added in a future update.