Gardens of Eden and amenability on cellular automata
The spectrum of a Gelfand pair , where is a nilpotent group, can be embedded in a Euclidean space. We prove that in general, the Schwartz functions on the spectrum are the Gelfand transforms of Schwartz -invariant functions on . We also show the converse in the case of the Gelfand pair , where is the free two-step nilpotent Lie group with three generators. This extends recent results for the Heisenberg group.
Let G be a group of automorphisms of a tree X (with set of vertices S) and H a kernel on S × S invariant under the action of G. We want to give an estimate of the -operator norm (1 ≤ r ≤ 2) of the operator associated to H in terms of a norm for H. This was obtained by U. Haagerup when G is the free group acting simply transitively on a homogeneous tree. Our result is valid when X is a locally finite tree and one of the orbits of G is the set of vertices at even distance from a given vertex; a technical...
Some extensions of the properties of invariant polynomials proved by Davis (1980), Chikuse (1980), Chikuse and Davis (1986) and Ratnarajah et al. (2005) are given for symmetric and Hermitian matrices.
The generalized notion of weak amenability, namely -weak amenability, where are continuous homomorphisms on a Banach algebra , was introduced by Bodaghi, Eshaghi Gordji and Medghalchi (2009). In this paper, the -weak amenability on the measure algebra , the group algebra and the Segal algebra , where is a locally compact group, are studied. As a typical example, the -weak amenability of a special semigroup algebra is shown as well.
In this paper, we analyze multi-dimensional quasi-asymptotically -almost periodic functions and their Stepanov generalizations as well as multi-dimensional Weyl -almost periodic type functions. We also analyze several important subclasses of the class of multi-dimensional quasi-asymptotically -almost periodic functions and reconsider the notion of semi--periodicity in the multi-dimensional setting, working in the general framework of Lebesgue spaces with variable exponent. We provide certain...
We consider various generalizations of linear homogeneous distributions on adeles and construct a number of algebras of non-linear generalized functions on adeles and totally disconnected groups such as the discrete adeles.
We investigate the amenability and its related homological notions for a class of -upper triangular matrix algebra, say , where is a Banach algebra equipped with a nonzero character. We show that is pseudo-contractible (amenable) if and only if is singleton and is pseudo-contractible (amenable), respectively. We also study pseudo-amenability and approximate biprojectivity of .