Interior multiple spikes in the shadow Gierer-Meinhardt system by Michal Kowalczyk, University of Utah 320 JTB, 3:20pm Monday, November 10, 1997 Abstract The Gierer-Mienhardt system models biochemical reactions of activator-inhibitor type. In such reactions spatial patterns of "islands" of high concentration of activator (spike layers) within the "sea" of essentially uniformly distributed inhibitor are present. The difference between the rates of diffusion of the reagents plays crucial role in forming of such patterns. In this talk I will discuss the existence of stationary spike layers in the case when the diffusion of the inhibitor is fast (the shadow G-M system). Mathematically we will be dealing with a singularly perturbed semilinear elliptic problem. In particular the geometric conditions for the location of spike layers will be given. Request for preprints and reprints to kowalcyk@math.utah.edu. This information can be found at http://www.math.utah.edu/research/