Theory of Stochastic Processes
A.A. 2024/25

Aggiornamento del 08.01.25
 

Lez.

Data

Argomento

 
L 1 (2h) 25.09.24
  • Introduction
  • Motivation
    • Brownian Motion: Einstein and Langevin description.
    • Birth-Death processes: Master equation.
    • Shot Noise: Stochastic Differential Equation.
L 2 (3h) 30.09.24
  • Motivation
    • Shot Noise: Stochastic Differential Equation.
  • Stochastic Processes
    • Definitions.
    • Bernoulli Trials.
    • Markov Processes.
    • The Chapman-Kolmogorov equation.
    • Continuous Markov processes; examples: Brownian motion and Cauchy process.
    • Differential Chapman-Kolmogorov equation.
L 3 (1h) 01.10.24
  • Markov Processes
    • The master equation: jump processes.
    • The Liouville equation: deterministic processes.
    • The Fokker-Planck equation: diffusive processes.
L 4 (2h) 02.10.24
  • Fokker-Planck Equation
    • Backward differential Chapman-Kolmogorov equation.
    • Forward Kramers-Moyal equation.
    • Stationary and homogeneous Markov Processes.
L 5 (3h) 07.10.24
  • Fokker-Planck Equation
    • The Wiener Process.
    • The Ornstein-Uhlembeck proceess.
    • The method of characteristics for quasilinear partial differential equations.
L 6 (1h) 08.10.24
  • Fokker-Planck Equation
    • Probability current and boundary conditions for the Fokker-Planck equation.
L 7 (2h) 09.10.24
  • Fokker-Planck Equation
    • Stationary solution for the one-dimensional homegeneous Fokker-Planck equation: Potential solutions.
    • Stationary solution in a gravitational field.
    • Stationary solution of the Ornstein-Uhlembeck process.
    • Stationary solution for the Brownian motion.
    • The eigenvalue method: Wiener process with absorbing and reflectin barriers.
L 8 (3h) 14.10.24
  • Fokker-Planck Equation
    • First Passage Time for homogeneous processes.
    • Escape over a potential barrier, the Arrhenius formula.
  • Stochastic Differential Equations
    • The Langevin equation and the Wiener process.
    • The stochastic integration: the Ito Integral.
    • Nonanticipating functions.
    • dW(t)2 and dW(t)2+N.
L 9 (1h) 15.10.24
  • Stochastic Differential Equations
    • The Stratonovich Integral.
    • The Ito differentiation rule.
    • The Dirac delta function and the Heaviside theta function.
L 10 (2h) 16.10.24
  • Stochastic Differential Equations
    • Numerical integration of SDE: Stochastic second order Runge-Kutta Algorithm.
L 11 (3h) 21.10.24
  • Stochastic Differential Equations
    • The Ito formula.
    • Ito SDE and Fokker-Planck equation.
    • Ito and Stratonovich SDE.
    • Stratonovich SDE and Fokker-Planck equation.
L 12 (1h) 22.10.24
  • Stochastic Differential Equations
    • Example: SDE with linear multiplicative noise.
    • Example: Linear oscillator with random frequency.
L 13 (2h) 23.10.24
  • Path Integral Methods for Stochastic Differential Equations
    • Path Integral formulation for additive white noise Langevin equations.
    • The Martin-Siggia-Rose-Janssen-de Domicis (MSRJD) Action.
    • The Onsager-Machlup-Graham-Bausch-Wegner (OMGBW) Action.
L 14 (3h) 28.10.23
  • Path Integral Methods for Stochastic Differential Equations
    • Derivation of the Fokker-Planck equation from the path integral.
    • Response functions and response fields.
    • Quadratic MSRJD action.
L 15 (1h) 29.10.24
  • Path Integral Methods for Stochastic Differential Equations
    • Example: The one dimensional Ornstein-Uhlembeck process.
L 16 (2h) 30.10.24
  • Path Integral Methods for Stochastic Differential Equations
    • Path Integral formulation for multiplicative white noise Langevin equations.
L 17 (3h) 04.11.24
  • Path Integral Methods for Stochastic Differential Equations
    • From Path Integral to Fokker-Planck equation for multiplicative white noise processes: state dependent diffusion.
    • Thermodynamic equilibrium conditions for multiplicative white noise processes.
    • Fluctuation-Dissipation Theorem for additive white noise processes.
L 18 (1h) 05.11.24
  • Path Integral Methods for Stochastic Differential Equations
    • Detailed Balance condition.
L 19 (2h) 06.11.24
  • Path Integral Methods for Stochastic Differential Equations
    • Fluctuation-Dissipation Theorem for multiplicative white noise processes.
  • Dynamical Field Theory
    • The Novikov and Wick theorems.
    • Perturbation theory in the nonlinearity (interaction).
    • Equazione di Dyson dinamica e Terorema FDT.
L 20 (3h) 11.11.24
  • Dynamical Field Theory
    • Perturbative evaluation of (equilibrium) two points functions.
    • The Dyson equation.
L 21 (1h) 12.11.24
  • Dynamical Field Theory
    • The Dyson equation for the zero-dimensional λϕ4 model: first order calculation.
    • Perturbation theory in the non linearity with non zero external field.
L 22 (2h) 13.11.24
  • Dynamical Field Theory
    • Dynamical Effective potential Γ[φ,φ̂].
    • Dynamical Effective potential for the Ornstein-Uhlembeck process.
    • Loop expansion of the Dynamical Effective potential.
L 23 (3h) 18.11.24
  • Dynamical Field Theory
    • Dynamical Effective potential for the zero-dimensional λϕ4 model: zero and one loop calculation.
    • Conditional Probability Function: the φ̂ ≠ 0 solution.
L 24 (1h) 19.11.24
  • Dynamical Field Theory
    • Dynamical Effective Potential and Conditional Probability Function.
    • Arrhenius Law.
L 25 (2h) 20.11.24
  • Dynamical Field Theory
    • Quantum averages over the Close Time Path (CTP) contour.
    • Bosonic Coherent States.
L 26 (3h) 25.11.24
  • Dynamical Field Theory
    • CTP calculation of Z[0] for the bosonic system Ĥ = ω0+ b̂.
    • CTP Green function for the bosonic system Ĥ = ω0+ b̂.
L 27 (1h) 26.11.24
  • Dynamical Field Theory
    • The Keldysh formalism.
L 28 (2h) 27.11.24
  • Dynamical Field Theory
    • Quantum Harmonic Oscillator.
  • Dynamical Field Theory for disordered systems
    • Quenched disorder average in statics and dynamics.
    • Random non-symmetric two-body interaction neural network model: averaged dynamical generating function.
L 29 (3h) 02.12.24
  • Dynamical Field Theory for disordered systems
    • The spherical p-spin and 2+p-spin spin-glass models: averaged dynamical generating function and effective dynamics.
L 30 (1h) 03.12.24
  • Non fatta
L 31 (2h) 04.12.23
  • Dynamical Field Theory for disordered systems
    • Equilibrium dynamics of the spherical 2+p-spin spin-glass models.
    • Ergodic dynamics of the 2+3-spin spin-glass model: critical slowing down and continuous transition.
L 32 (3h) 09.12.24
  • Dynamical Field Theory for disordered systems
    • Ergodic dynamics of the 2+3-spin spin-glass model: critical slowing down and continuous transition.
    • Ergodic dynamics of the 2+3-spin spin-glass model: dynamical arrest and discontinuous transition.
L 33 (1h) 10.12.24
  • Non fatta
L 34 (2h) 11.12.24
  • Dynamical Field Theory for disordered systems
    • Non-ergodic dynamcis of the 2+3-spin spin-glass model: two-steps relaxation, dynamical marginal condition and 1RSB phase.
L 35 (3h) 16.12.24
  • Non fatta
L 36 (1h) 17.12.24
  • Non fatta
L 37 (2h) 18.12.24
  • Non fatta
L 38 (1h) 07.01.25
  • Non fatta
L 39 (2h) 08.01.25
  • Dynamical Field Theory for disordered systems
    • Path-Integral approach to a fully connected neural network model with random independent asymmetric couplings.
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