Application To Finance
In finance, Girsanov theorem is used each time one needs to derive an asset's or rate's dynamics under a new probability measure. The most well known case is moving from historic measure P to risk neutral measure Q which is done - in Black Scholes framework - via Radon–Nikodym derivative:

where r denotes the instanteaneous risk free rate, the asset's drift and its volatility.
Other classical applications of Girsanov theorem are quanto adjustments and the calculation of forwards' drifts under LIBOR market model.
Read more about this topic: Girsanov Theorem
Famous quotes containing the words application to, application and/or finance:
“Five oclock tea is a phrase our rude forefathers, even of the last generation, would scarcely have understood, so completely is it a thing of to-day; and yet, so rapid is the March of the Mind, it has already risen into a national institution, and rivals, in its universal application to all ranks and ages, and as a specific for all the ills that flesh is heir to, the glorious Magna Charta.”
—Lewis Carroll [Charles Lutwidge Dodgson] (18321898)
“Courage is resistance to fear, mastery of fearnot absence of fear. Except a creature be part coward it is not a compliment to say it is brave; it is merely a loose application of the word. Consider the flea!incomparably the bravest of all the creatures of God, if ignorance of fear were courage.”
—Mark Twain [Samuel Langhorne Clemens] (18351910)
“There is an enormous chasm between the relatively rich and powerful people who make decisions in government, business, and finance and our poorer neighbors who must depend on these decisions to alleviate the problems caused by their lack of power and influence.”
—Jimmy Carter (James Earl Carter, Jr.)