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Foundations of theoretical physics

About - Set Theory and Foundations of mathematics - Other topics and links
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Introductions

List of physical theories that will progressively link to other pages presenting each theory.
An exploration of physics by dimensional analysis : telling a lot of fundamental physics and the amplitudes of diverse effects mainly by multiplying quantities. Some sections have been moved to separate pages:

The speed of light and astronomical distances
The energy of nuclear reactions ; The radius of nuclei
Electromagnetism
The gravitational constant
Effects of General Relativity
The parameters of the atomic structure
The compressibility of condensed matter
The speed of the sound in condensed matter
Temperature

(to be continued)

Expositions of specific theories

Special relativity

Special Relativity theory: Minkowski geometry (improved in autumn 2016 but still incomplete, will need more developments on geometry; relativistic mechanics not written yet)

Principle of least action (draft)
Conservation laws (stub)
Comments on the Lagrangian of the electromagnetic field

For a logical transition from relativistic mechanics to statistical physics and quantum physics I would see good to insert a study of Symplectic geometry. A good book I know on the topic is Structure of dynamical systems by Jean-Marie Souriau (also in French).

General relativity:

• The different notions of curvature in geometry
• Cosmology in General Relativity (evolution of the expansion, cosmological constant)
• The Einstein field equation
• Black holes

Concepts of entropy

• Thermodynamics : classical entropy
• Entropy in information theory
• Entropy in statistical physics
• The simplest proof of the ideal gas law
• Links to other sites on entropy

Quantum physics

Introduction to quantum physics for philosophers (pdf slides, May 2019 ; assumes the above understanding of entropy) : short clarified version with figures, of the main ideas from the below previously written texts:

• Articulations between quantum and classical physics (wave/particle duality, conservation of energy)
• Geometric expression of Markov processes
• Quantum states and measurements
• Quantum correlations
• The EPR paradox
• The double-slit experiment
• Quantum entropy (old draft, to be revised later)
• Quantum decoherence
• Interpretations of quantum physics
  • Copenhagen
  • de Broglie-Bohm interpretation (Bohmian mechanics)
  • The Many-worlds interpretation
    • Notes on time orientation and the big bang
  • Spontaneous collapse theories
  • The Mind makes collapse interpretation
    • The Mind makes collapse interpretation of the EPR paradox
    • Many links
    • Problems with Stapp's views
    • More...

Other

Tensors and tensor products.
Solved physics problems (for now just one thing about gravitation)