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**Uniform bounds for point cohomology of $\ell^1(\mathbb Z_+)$ and related algebras.** / Choi, Yemon.

Research output: Contribution to Journal/Magazine › Journal article › peer-review

Choi, Y 2009, 'Uniform bounds for point cohomology of $\ell^1(\mathbb Z_+)$ and related algebras', *Journal of Mathematical Analysis and Applications*, vol. 358, no. 2, pp. 249-260. https://doi.org/10.1016/j.jmaa.2009.05.002

Choi, Y. (2009). Uniform bounds for point cohomology of $\ell^1(\mathbb Z_+)$ and related algebras. *Journal of Mathematical Analysis and Applications*, *358*(2), 249-260. https://doi.org/10.1016/j.jmaa.2009.05.002

Choi Y. Uniform bounds for point cohomology of $\ell^1(\mathbb Z_+)$ and related algebras. Journal of Mathematical Analysis and Applications. 2009 Oct 15;358(2):249-260. doi: 10.1016/j.jmaa.2009.05.002

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title = "Uniform bounds for point cohomology of $\ell^1(\mathbb Z_+)$ and related algebras",

abstract = "The point cohomology of the convolution algebra ℓ1(Z+) is known to vanish in degrees 2 and above. We sharpen this result by obtaining splitting maps whose norms are bounded independently of the choice of point module. Our construction is a by-product of new estimates on projectivity constants of maximal ideals in ℓ1(Z+). Analogous results are obtained for some other L1-algebras which arise from {\textquoteleft}rank one{\textquoteright} subsemigroups of R+.",

keywords = "Point cohomology, Semigroup algebra , Uniformly bounded solution of cohomology problems , Flat Banach module , Maximal ideal",

author = "Yemon Choi",

year = "2009",

month = oct,

day = "15",

doi = "10.1016/j.jmaa.2009.05.002",

language = "English",

volume = "358",

pages = "249--260",

journal = "Journal of Mathematical Analysis and Applications",

issn = "0022-247X",

publisher = "Academic Press Inc.",

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T1 - Uniform bounds for point cohomology of $\ell^1(\mathbb Z_+)$ and related algebras

AU - Choi, Yemon

PY - 2009/10/15

Y1 - 2009/10/15

N2 - The point cohomology of the convolution algebra ℓ1(Z+) is known to vanish in degrees 2 and above. We sharpen this result by obtaining splitting maps whose norms are bounded independently of the choice of point module. Our construction is a by-product of new estimates on projectivity constants of maximal ideals in ℓ1(Z+). Analogous results are obtained for some other L1-algebras which arise from ‘rank one’ subsemigroups of R+.

AB - The point cohomology of the convolution algebra ℓ1(Z+) is known to vanish in degrees 2 and above. We sharpen this result by obtaining splitting maps whose norms are bounded independently of the choice of point module. Our construction is a by-product of new estimates on projectivity constants of maximal ideals in ℓ1(Z+). Analogous results are obtained for some other L1-algebras which arise from ‘rank one’ subsemigroups of R+.

KW - Point cohomology

KW - Semigroup algebra

KW - Uniformly bounded solution of cohomology problems

KW - Flat Banach module

KW - Maximal ideal

U2 - 10.1016/j.jmaa.2009.05.002

DO - 10.1016/j.jmaa.2009.05.002

M3 - Journal article

VL - 358

SP - 249

EP - 260

JO - Journal of Mathematical Analysis and Applications

JF - Journal of Mathematical Analysis and Applications

SN - 0022-247X

IS - 2

ER -