Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Idempotents of large norm and homomorphisms of Fourier algebras   We provide necessary and sufficient conditions for the existence of
idempotents of arbitrarily large norms in the Fourier algebra A(G) and the
Fourier-Stieltjes algebra B(G) of a locally compact group G. We prove that the
existence of idempotents of arbitrarily large norm in B(G) implies the
existence of homomorphisms of arbitrarily large norm from A(H) into B(G) for
every locally compact group H. A partial converse is also obtained: the
existence of homomorphisms of arbitrarily large norm from A(H) into B(G) for
some amenable locally compact group H implies the existence of idempotents of
arbitrarily large norm in B(G).

22
The categories of this paper are: chao-dyn
21
The categories of this paper are: adap-org
26
The categories of this paper are: bayes-an
4
The categories of this paper are: cond-mat
3
The categories of this paper are: physics
37
The categories of this paper are: supr-con
17
The categories of this paper are: q-fin
23
The categories of this paper are: solv-int
28
The categories of this paper are: alg-geom
30
The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph
16
The categories of this paper are: stat
25
The categories of this paper are: patt-sol
1
The categories of this paper are: cs
12
The categories of this paper are: nucl-th
7
The categories of this paper are: hep-th