Abstract:
Generalized Honda formal groups are the next step in a chain of generalizations the multiplicative formal group – Lubin-Tate formal groups — relative Lubin-Tate formal groups — Honda formal groups. This paper continues the study of properties of this class of formal groups focusing on their homomorphisms. In particular, we show that every homomorphism of generalized Honda formal groups can be expressed as a composition of a chain of distinguished isogenies and an isomorphism. It implies that for any generalized Honda formal group of finite height an isogeny class contains only a finite number of isomorphism classes. The results obtained give an idea of the structure of homomorphisms of formal groups over an arbitrary $p$-adic ring of integers.
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