Bálint Tóth:

Conjugate Diffusions on R_+ and Generalized Ray-Knight processes

We define the notion of conjugacy of a pair of diffusions on the positive half-line R_+. Typical examples of conjugate diffusions are pairs of squared Bessel processes of generalized dimension δ, respectively 2-δ (the latter one being stopped at first hitting of 0). Using pairs of conjugate diffusions we construct processes with a structure similar to the processes arising in the Ray-Knight description of Brownian local time. These generalized Ray-Knight processes arise naturally as scaling limits of the local time of non-Markovian Random walks. The main technical result of the paper sheds light on the intimate probabilistic content of conjugacy.

balint@math-inst.hu