TY - GEN

T1 - Multidimensional catalytic branching random walk with regularly varying tails

AU - Bulinskaya, Ekaterina Vl

PY - 2019/7/8

Y1 - 2019/7/8

N2 - Catalytic branching random walk (CBRW) describes reproduction of particles and their movement in space. The particles may give offspring in the presence of catalysts. Consider CBRW model where the particles perform a random walk over a multidimensional lattice, without procreation outside the catalysts. The latter take a finite number of fixed positions at the lattice. We study the particles spread in case of non-extinction of population initiated by a single particle. The rate of population spread depends essentially on the distribution tails of the random walk jumps. Consider the jumps with independent (or close to independent) components having regularly varying “heavy’’ tails. The main results show that, after a proper normalization of positions, in the time limit the particles concentrate on a random set, located at the coordinate axes. For a two-dimensional case, the limiting set forms a cross, and, for any higher dimension d, it is a collection of d segments containing the origin. The joint distribution of such segments lengths is found and the time-limit is understood in the sense of weak convergence. This radically differs from the known results for both the CBRW with “light” and semi-exponential distribution tails of the random walk jumps.

AB - Catalytic branching random walk (CBRW) describes reproduction of particles and their movement in space. The particles may give offspring in the presence of catalysts. Consider CBRW model where the particles perform a random walk over a multidimensional lattice, without procreation outside the catalysts. The latter take a finite number of fixed positions at the lattice. We study the particles spread in case of non-extinction of population initiated by a single particle. The rate of population spread depends essentially on the distribution tails of the random walk jumps. Consider the jumps with independent (or close to independent) components having regularly varying “heavy’’ tails. The main results show that, after a proper normalization of positions, in the time limit the particles concentrate on a random set, located at the coordinate axes. For a two-dimensional case, the limiting set forms a cross, and, for any higher dimension d, it is a collection of d segments containing the origin. The joint distribution of such segments lengths is found and the time-limit is understood in the sense of weak convergence. This radically differs from the known results for both the CBRW with “light” and semi-exponential distribution tails of the random walk jumps.

KW - Catalytic branching random walk

KW - Heavy tails

KW - Population front

KW - Regularly varying tails

KW - Spread of population

KW - Supercritical regime

UR - http://www.scopus.com/inward/record.url?scp=85072808965&partnerID=8YFLogxK

U2 - 10.1145/3343485.3343493

DO - 10.1145/3343485.3343493

M3 - Conference contribution

AN - SCOPUS:85072808965

T3 - ACM International Conference Proceeding Series

SP - 6

EP - 13

BT - ICoMS 2019 - Proceedings of 2019 2nd International Conference on Mathematics and Statistics

PB - Association for Computing Machinery

T2 - 2nd International Conference on Mathematics and Statistics, ICoMS 2019

Y2 - 8 July 2019 through 10 July 2019

ER -