Module 3:Branching process, Application of Markov chains, Markov Processes with discrete and                 continuous state space
  Lecture 12:Weiner Process
 


In order to find the differential equations of Weiner process we are interestd to find the infinitesimal shift in the particle's position as time progresses. Assume the probabilities of  and  are independent of  and . Then using Taylor series expansion we have:

Here we consider
Thus:

(3.10)

We also know that

(3.11)

Using (3.9), (3.10) and (3.11) and after some simplification along with the fact that ,  we obtain

(3.12)