Examples of an additive category equipped with kernels and cokernels but fails to be abelian












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In all the examples of additive but nonabelian categories that I am aware of, kernels/cokernels don't exist.



I wonder if there is an additive category where morphisms have kernels and cokernels that fails to be an abelian category. i.e. not every mono/epi is the kernel/cokernel of its cokernel/kernel.










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  • $begingroup$
    See for example math.stackexchange.com/questions/2467551/….
    $endgroup$
    – Arnaud D.
    Feb 1 at 19:04
















0












$begingroup$


In all the examples of additive but nonabelian categories that I am aware of, kernels/cokernels don't exist.



I wonder if there is an additive category where morphisms have kernels and cokernels that fails to be an abelian category. i.e. not every mono/epi is the kernel/cokernel of its cokernel/kernel.










share|cite|improve this question









$endgroup$












  • $begingroup$
    See for example math.stackexchange.com/questions/2467551/….
    $endgroup$
    – Arnaud D.
    Feb 1 at 19:04














0












0








0





$begingroup$


In all the examples of additive but nonabelian categories that I am aware of, kernels/cokernels don't exist.



I wonder if there is an additive category where morphisms have kernels and cokernels that fails to be an abelian category. i.e. not every mono/epi is the kernel/cokernel of its cokernel/kernel.










share|cite|improve this question









$endgroup$




In all the examples of additive but nonabelian categories that I am aware of, kernels/cokernels don't exist.



I wonder if there is an additive category where morphisms have kernels and cokernels that fails to be an abelian category. i.e. not every mono/epi is the kernel/cokernel of its cokernel/kernel.







category-theory






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share|cite|improve this question










asked Feb 1 at 18:10









No OneNo One

2,1101519




2,1101519












  • $begingroup$
    See for example math.stackexchange.com/questions/2467551/….
    $endgroup$
    – Arnaud D.
    Feb 1 at 19:04


















  • $begingroup$
    See for example math.stackexchange.com/questions/2467551/….
    $endgroup$
    – Arnaud D.
    Feb 1 at 19:04
















$begingroup$
See for example math.stackexchange.com/questions/2467551/….
$endgroup$
– Arnaud D.
Feb 1 at 19:04




$begingroup$
See for example math.stackexchange.com/questions/2467551/….
$endgroup$
– Arnaud D.
Feb 1 at 19:04










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