api: YAML JSON TOON Database
version: 1.0.0
format: json
dataset:
  id: 68
  slug: quantum-mechanics-basics
  title: "Quantum Mechanics: Core Principles and Phenomena"
  description: "Foundations of quantum mechanics: wave-particle duality, Schrödinger equation, Heisenberg uncertainty, quantum superposition, entanglement, and measurement problem."
  summary: "The central principles of quantum mechanics and the phenomena that illustrate them: wave-particle duality, the Schrodinger equation, the uncertainty principle, superposition, entanglement and measurement, each with key experiments, a formula and its significance."
  use_when:
    - You need an accurate one-paragraph statement of a quantum principle.
    - You are connecting a principle to the experiment that demonstrated it.
  caveats:
    - Quantum mechanics is mathematically settled but its interpretation (what measurement means) is still debated.
    - Popular descriptions of superposition and entanglement often overstate what they imply; prefer the formal statement.
  related:
    - classical-mechanics
    - electromagnetism-basics
    - optics-fundamentals
  category: Physics
  category_slug: physics
  tags: physics,quantum-mechanics,schrodinger,heisenberg,superposition,entanglement,wave-particle-duality
  view_count: 0
  created_at: 1778695229
  updated_at: 1778695229
  entry_count: 7
  fields:
    - section: principles
      field: name
      type: string
      example: Wave-Particle Duality
    - section: principles
      field: description
      type: string
      example: Matter and light exhibit both wave and particle…
    - section: principles
      field: key_experiments
      type: array
      example: "[3 items]"
    - section: principles
      field: formula
      type: string
      example: "de Broglie wavelength: λ = h/p"
    - section: principles
      field: significance
      type: string
      example: Fundamental departure from classical physics; a…
    - section: principles
      field: interpretation
      type: string
      example: "|ψ(x)|² gives probability density of finding pa…"
    - section: principles
      field: implications
      type: string
      example: Explains atomic stability (electron can't colla…
    - section: principles
      field: famous_example
      type: string
      example: Schrödinger's cat thought experiment (cat simul…
    - section: principles
      field: experimental_verification
      type: string
      example: Aspect experiment (1982) confirmed Bell inequal…
    - section: principles
      field: interpretations
      type: array
      example: "[3 items]"
    - section: principles
      field: applies_to
      type: string
      example: Fermions (electrons, protons, neutrons, quarks)…
data:
  principles:
    - name: Wave-Particle Duality
      description: Matter and light exhibit both wave and particle properties depending on experimental setup
      key_experiments:
        - Double-slit experiment (interference pattern for electrons/photons)
        - Photoelectric effect (light as particles/photons)
        - Davisson-Germer experiment (electron diffraction)
      formula: "de Broglie wavelength: λ = h/p"
      significance: Fundamental departure from classical physics; all matter has wave nature
    - name: Schrödinger Equation
      description: Fundamental equation of non-relativistic quantum mechanics; describes evolution of quantum state
      formula: iℏ ∂ψ/∂t = Ĥψ (time-dependent); Ĥψ = Eψ (time-independent)
      significance: Predicts probability amplitudes; solutions (wavefunctions) give energy levels and spatial distributions
      interpretation: "|ψ(x)|² gives probability density of finding particle at position x"
    - name: Heisenberg Uncertainty Principle
      description: Fundamental limit on simultaneous precision of complementary observables
      formula: Δx · Δp ≥ ℏ/2; ΔE · Δt ≥ ℏ/2
      significance: Not a measurement limitation but intrinsic property of quantum systems; conjugate variables cannot be simultaneously sharp
      implications: Explains atomic stability (electron can't collapse into nucleus), zero-point energy
    - name: Quantum Superposition
      description: Quantum system exists in all possible states simultaneously until measured
      formula: "|ψ⟩ = α|0⟩ + β|1⟩ where |α|² + |β|² = 1"
      significance: Basis of quantum computing (qubits); demonstrated by double-slit interference
      famous_example: Schrödinger's cat thought experiment (cat simultaneously alive and dead)
    - name: Quantum Entanglement
      description: Two or more particles share a quantum state; measurement of one instantaneously affects the other regardless of distance
      formula: "|ψ⟩ = (|00⟩ + |11⟩)/√2 (Bell state)"
      significance: Violates local realism (Bell's theorem); basis for quantum cryptography and teleportation
      experimental_verification: Aspect experiment (1982) confirmed Bell inequality violation; 2022 Nobel Prize
    - name: Quantum Measurement (Collapse)
      description: Measurement causes wavefunction to collapse to an eigenstate of the measured observable
      interpretations:
        - name: Copenhagen
          description: Collapse is fundamental; measurement creates reality
        - name: Many-Worlds
          description: No collapse; all outcomes realized in branching universes
        - name: Decoherence
          description: Apparent collapse due to entanglement with environment
      significance: Measurement problem remains unresolved; central mystery of quantum foundations
    - name: Pauli Exclusion Principle
      description: No two identical fermions can occupy the same quantum state simultaneously
      formula: ψ(r₁,r₂) = -ψ(r₂,r₁) (antisymmetric wavefunction for fermions)
      significance: Explains electron shell structure, periodic table, stability of matter, neutron star degeneracy pressure
      applies_to: Fermions (electrons, protons, neutrons, quarks); not bosons (photons, gluons)