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Physics
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Foundations
1.1
The Principle of Least Action
1.2
Lagrangian Mechanics
1.3
Symmetries & Conservation
1.4
Hamiltonian Mechanics
1.5
Mathematical Foundations
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Quantum Mechanics
2.1
QM Foundations
2.2
Exactly Solvable Problems
2.3
Approximation Methods
2.4
Entanglement & Measurement
2.5
Interpretations
2.6
Path Integrals
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Electromagnetism
3.1
Maxwell's Equations
3.2
Electromagnetic Waves
3.3
Gauge Invariance
3.4
Relativistic Formulation
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Special Relativity
4.1
Lorentz Transformations
4.2
Spacetime Diagrams
4.3
4-Vectors & Invariants
4.4
Relativistic Mechanics
4.5
E = mc²
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Statistical Physics
5.1
Entropy & the Second Law
5.2
Ensembles
5.3
Quantum Statistics
5.4
Phase Transitions
5.5
Information & Entropy
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General Relativity
6.1
Differential Geometry
6.2
Einstein Field Equations
6.3
Schwarzschild Solution
6.4
Black Holes
6.5
Gravitational Waves
6.6
Cosmological Solutions
▶
Quantum Field Theory
7.1
Free Fields
7.2
Interactions
7.3
Renormalization
7.4
Gauge Theories
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The Standard Model
8.1
Particle Content
8.2
Electroweak Unification
8.3
QCD
8.4
Neutrino Physics
8.5
Beyond the Standard Model
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Cosmology
9.1
The Big Bang
9.2
Inflation
9.3
CMB Physics
9.4
Dark Matter
9.5
Dark Energy
9.6
Structure Formation
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Frontiers
10.1
Quantum Gravity
10.2
Foundational Questions
10.3
Information & Physics
10.4
Cross-Field Connections
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Research Frontiers
11.1
Holography & AdS/CFT
11.2
Entanglement & Spacetime
11.3
The Island Formula
11.4
Holographic Error Correction
11.5
The Amplituhedron
11.6
The Swampland Program
11.7
Complexity & Black Holes
11.8
Topological Order & Fractons
11.9
Information Geometry
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Open Problems
12.1
Black Hole Information Paradox
12.2
The Dark Energy Problem
12.3
The Hubble Tension
12.4
Cosmic Topology
12.5
Novel Directions
Lesson 12.4 · 12. Open Problems
Cosmic Topology
← 12.3 The Hubble Tension
12.5 Novel Directions →