Girsanov theorem

Girsanov's theorem is a fundamental result in the theory of stochastic processes, particularly in the field of stochastic calculus and quantitative finance. It provides a way to change the probability measure under which a stochastic process is defined, transforming it into another process that may have different characteristics. This is particularly useful in financial mathematics for pricing derivatives and in risk management. ### Key Concepts: 1. **Stochastic Processes**: A stochastic process is a collection of random variables indexed by time or space.