Foundations

Measure-Theoretic Probability

  • Measure Theory Notes
    • Measure Spaces
    • Sample spaces, Events, Probability Spaces
    • σ-algebras and Measurable spaces
    • Probability measures and axioms (Kolmogorov’s axioms)
  • Random Variables and Distributions
    • Measurable functions, distribution functions
  • Expectation and Moments
  • Random Variable Convergence
    • Convergence Almost Surely, Mean, Probability, Law
    • Borel-Cantelli Lemma
    • Uniform Integrability
    • Skorohod’s Representation Theorem
  • Convergence Theorems
    • Monotone Convergence Theorem
    • Dominated Convergence Theorem
  • Lp Spaces
  • Limit Theorems
  • Large Deviations
    • Cramér Theorem
    • Sanov Theorem
  • Functional Limit Theorems
    • Donsker Invariance Principle
    • Prohorov Theorem (tightness)
  • Conditional Expectation
    • Hilbert Spaces
    • Projection Theorem

Discrete-Time Stochastic Processes

  • Markov Chains 1
    • Transition matrices
    • Chapman-Kolmogorov equations
    • Classification of states (recurrent, transient, ergodic)
    • Stationary distributions and convergence
  • Martingale Theory
    • Filtrations & Adapted Processes
    • Martingale convergence theorem
    • Optional stopping theorem
      • Stopping Times
    • Doob’s decomposition and inequalities
  • Renewal Theory
    • Renewal function, renewal reward processes
    • Elementary and key renewal theorems
    • Applications: queues, reliability theory
  • Branching Processes
    • Galton-Watson Branching Process
    • Extinction Probabilities
  • Random Walks
    • Hitting Probabilities

Continuous-Time Stochastic Processes


  • Poisson Processes
    • Inter-arrival times, memoryless property
    • Compound Poisson processes
  • Continuous-Time Markov Chains
    • Infinitesimal generator,
    • Kolmogorov
      • Kolmogorov Forward Equation
      • Kolmogorov Backward Equation
    • Birth-death processes
  • Brownian Motion
    • Construction and properties (scaling, Markov, Gaussianity)
    • Reflection principle, hitting times
    • Functional CLT → Brownian motion as scaling limit

Stochastic Calculus


  • Stochastic Calculus
  • Itô Integration
    • Itô isometry
    • Itô’s Lemma
      • Multidimensional version
      • Change-of-variable formula
    • P-Variation
  • Stochastic Differential Equations (SDEs)
  • Girsanov’s Theorem
    • Change of measure
    • Radon–Nikodym derivative
    • Risk-neutral pricing in finance
  • Optimal Stopping and Control
    • Snell envelope
    • Hamilton–Jacobi–Bellman equations
    • Dynamic programming principle
  • Mean Field Games and McKean-Vlasov SDEs
    • Nash equilibria in continuum agent models
    • Forward-backward SDEs

Advanced Topics


  • Interacting Particle Systems and Mean Field Models
    • Propagation of chaos
    • McKean–Vlasov equations
  • Queuing Theory
    • M/M/1, M/G/1, G/G/1 queues
    • Little’s Law, heavy traffic approximations
  • Large Deviations and Rare Event Simulation
    • Importance sampling, importance splitting
    • Freidlin–Wentzell theory for SDEs
  • Connections with PDEs
    • Probabilistic representations (Feynman–Kac, Dynkin’s formula)
    • Stochastic representations for solutions to elliptic and parabolic PDEs
  • Measure-Valued and Distribution-Valued Processes
    • Superprocesses, stochastic PDEs
    • Applications in population dynamics and filtering
  • Stochastic Partial Differential Equations (SPDEs)
    • Regularity structures (Hairer)
    • Paracontrolled calculus
  • Stochastic Topology and Random Geometry
    • Stochastic homology, random graphs, and geometric complexes
  • Interplay with Functional Analysis
    • Dirichlet forms, Gaussian Hilbert spaces
    • Infinite-dimensional stochastic analysis (Malliavin calculus)