🔬 Discovery

Itô stochastic calculus

Cálculo estocástico de Itô

Date
1944 · confidence high
Place
Tokyo, Japan
Credited to
Kiyosi Itô; Wiener's Brownian motion (1923)
People
👤 Kiyoshi Itō1915–2008
Field
Knowledge & symbols

What was discovered

An integral with respect to Brownian motion and Itô's formula (the chain rule for random processes), which makes it possible to set up stochastic differential equations. The basis of financial mathematics and signal filtering.

Published in Japanese during the war, it took years to become known in the West.

What it led to

  • stochastic differential equations
  • the Black-Scholes model
  • the Kalman-Bucy filter
  • statistical physics
🕸️ View in the graph

Built on

  • Kolmogorov axioms
  • Wiener process
  • Bachelier (1900)

Made possible

Links