Some questions aboutp-groups

Some Foundational Questions concerning Differential Algebraic Groups

In this paper we solve some problems posed by Kolchin about differential algebraic groups. The main result (from which the others follow) is the embeddability of any differential algebraic group in an algebraic group. A crucial intermediate result, and one of independent interest, is a generalisation of Weil’s theorem on recovering an algebraic group from birational data, to pro-algebraic groups.

Some questions on subgroups of 3-dimensional Poincaré duality groups

We state a number of open questions on 3-dimensional Poincaré duality groups and their subgroups, motivated by considerations from 3-manifold topology. AMS Subject classification (1985): Primary 57N10, Secondary 57M05, 20J05

Some Questions

These are some questions I am every interested in. Your solution to any question in this draft would be welcome. I keep updating this draft. 1. Classical recursion theory We use R to denote the partial ordering of r.e. degrees and Dn to denote the partial ordering of n-r.e. degrees. Yang and I proved thatR is not a Σ1-substructure of Dn. Question 1.1 (Khoussainov). For n > 1, is there a functio...

E-Learning: some unanswered questions

Some Questions on Unique

The simplest type of integral extension of a unique factorization domain B is obtained by adjoining to B an n-th root of one of its elements; that is, by forming the ring Bn = B[z]=(z n g), where n 2 Z and g 2 B. When n = 1, Bn = B. When n 2 it is natural to ask for what g 2 B will unique factorization be preserved? The case where B is a polynomial ring over an algebraically closed eld k immedi...