From Wikipedia, the free encyclopedia
Theorem of mathematics
In mathematics, the Cohen–Hewitt factorization theorem states that if is a left module over a Banach algebra
with a left approximate unit
, then an element
of
can be factorized as a product
(for some
and
) whenever
. The theorem was introduced by Paul Cohen (1959) and Edwin Hewitt (1964).
References
[edit]- Cohen, Paul J. (1959), "Factorization in group algebras", Duke Mathematical Journal, 26 (2): 199–205, doi:10.1215/s0012-7094-59-02620-1, MR 0104982
- Hewitt, Edwin (1964), "The ranges of certain convolution operators", Mathematica Scandinavica, 15: 147–155, doi:10.7146/math.scand.a-10738, MR 0187016
- Mortini, Raymond (May 2019), "A Simpler Proof of Cohen's Factorization Theorem", The American Mathematical Monthly, 126 (5): 459–463
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