# Extensions of covariantly finite subcategories revisited

Czechoslovak Mathematical Journal (2019)

- Volume: 69, Issue: 2, page 403-415
- ISSN: 0011-4642

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topHe, Jing. "Extensions of covariantly finite subcategories revisited." Czechoslovak Mathematical Journal 69.2 (2019): 403-415. <http://eudml.org/doc/294451>.

@article{He2019,

abstract = {Extriangulated categories were introduced by Nakaoka and Palu by extracting the similarities between exact categories and triangulated categories. A notion of homotopy cartesian square in an extriangulated category is defined in this article. We prove that in an extriangulated category with enough projective objects, the extension subcategory of two covariantly finite subcategories is covariantly finite. As an application, we give a simultaneous generalization of a result of X. W. Chen (2009) and of a result of R. Gentle, G. Todorov (1996).},

author = {He, Jing},

journal = {Czechoslovak Mathematical Journal},

keywords = {extriangulated category; covariantly finite subcategory},

language = {eng},

number = {2},

pages = {403-415},

publisher = {Institute of Mathematics, Academy of Sciences of the Czech Republic},

title = {Extensions of covariantly finite subcategories revisited},

url = {http://eudml.org/doc/294451},

volume = {69},

year = {2019},

}

TY - JOUR

AU - He, Jing

TI - Extensions of covariantly finite subcategories revisited

JO - Czechoslovak Mathematical Journal

PY - 2019

PB - Institute of Mathematics, Academy of Sciences of the Czech Republic

VL - 69

IS - 2

SP - 403

EP - 415

AB - Extriangulated categories were introduced by Nakaoka and Palu by extracting the similarities between exact categories and triangulated categories. A notion of homotopy cartesian square in an extriangulated category is defined in this article. We prove that in an extriangulated category with enough projective objects, the extension subcategory of two covariantly finite subcategories is covariantly finite. As an application, we give a simultaneous generalization of a result of X. W. Chen (2009) and of a result of R. Gentle, G. Todorov (1996).

LA - eng

KW - extriangulated category; covariantly finite subcategory

UR - http://eudml.org/doc/294451

ER -

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