term for concrete category with initial morphism for each element












1














I need a term for a concrete category over Set with a distinguished object $i,$ such that the morphisms from $i$ correspond to elements of the other objects. More formally, for every object $o$ and every element $x in o,$ there is exactly one morphism $m_{o,x}: i to O.$ Is this an established concept, and, if so, what is the nomenclature.



Note that the terms initial and pointed already have other meanings in category theory.



The question arose while revising https://arxiv.org/abs/1801.05775










share|cite|improve this question









New contributor




shmuel is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.




















  • Hi, did you write that paper?
    – magma
    Dec 28 '18 at 14:34










  • Do you mean something like the one-point set in category Set ?
    – magma
    Dec 28 '18 at 14:35
















1














I need a term for a concrete category over Set with a distinguished object $i,$ such that the morphisms from $i$ correspond to elements of the other objects. More formally, for every object $o$ and every element $x in o,$ there is exactly one morphism $m_{o,x}: i to O.$ Is this an established concept, and, if so, what is the nomenclature.



Note that the terms initial and pointed already have other meanings in category theory.



The question arose while revising https://arxiv.org/abs/1801.05775










share|cite|improve this question









New contributor




shmuel is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.




















  • Hi, did you write that paper?
    – magma
    Dec 28 '18 at 14:34










  • Do you mean something like the one-point set in category Set ?
    – magma
    Dec 28 '18 at 14:35














1












1








1


1





I need a term for a concrete category over Set with a distinguished object $i,$ such that the morphisms from $i$ correspond to elements of the other objects. More formally, for every object $o$ and every element $x in o,$ there is exactly one morphism $m_{o,x}: i to O.$ Is this an established concept, and, if so, what is the nomenclature.



Note that the terms initial and pointed already have other meanings in category theory.



The question arose while revising https://arxiv.org/abs/1801.05775










share|cite|improve this question









New contributor




shmuel is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.











I need a term for a concrete category over Set with a distinguished object $i,$ such that the morphisms from $i$ correspond to elements of the other objects. More formally, for every object $o$ and every element $x in o,$ there is exactly one morphism $m_{o,x}: i to O.$ Is this an established concept, and, if so, what is the nomenclature.



Note that the terms initial and pointed already have other meanings in category theory.



The question arose while revising https://arxiv.org/abs/1801.05775







category-theory






share|cite|improve this question









New contributor




shmuel is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.











share|cite|improve this question









New contributor




shmuel is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.









share|cite|improve this question




share|cite|improve this question








edited Dec 26 '18 at 19:54









user376343

2,8382822




2,8382822






New contributor




shmuel is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.









asked Dec 26 '18 at 19:47









shmuel

1062




1062




New contributor




shmuel is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.





New contributor





shmuel is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.






shmuel is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.












  • Hi, did you write that paper?
    – magma
    Dec 28 '18 at 14:34










  • Do you mean something like the one-point set in category Set ?
    – magma
    Dec 28 '18 at 14:35


















  • Hi, did you write that paper?
    – magma
    Dec 28 '18 at 14:34










  • Do you mean something like the one-point set in category Set ?
    – magma
    Dec 28 '18 at 14:35
















Hi, did you write that paper?
– magma
Dec 28 '18 at 14:34




Hi, did you write that paper?
– magma
Dec 28 '18 at 14:34












Do you mean something like the one-point set in category Set ?
– magma
Dec 28 '18 at 14:35




Do you mean something like the one-point set in category Set ?
– magma
Dec 28 '18 at 14:35










1 Answer
1






active

oldest

votes


















6














If what you're after is a concrete category where $U$ is representable, then such categories are called representably concrete.






share|cite|improve this answer





















  • What I was looking for is probably the term generator (or separator.), but the definitions in ncatlab.org/nlab/show/separator and en.wikipedia.org/wiki/Generator_(category_theory) don't match. I need the term as defined in Wiki. Also, is there a term for a category with a generator?
    – shmuel
    Dec 26 '18 at 21:23










  • @shmuel - Isn't the definition in one of those just the contrapositive of the other?
    – Malice Vidrine
    Dec 26 '18 at 22:28










  • No; the nlab definition doesn't require that there be arrows from the generator to every other object.
    – shmuel
    Dec 27 '18 at 20:19











Your Answer





StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");

StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "69"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});

function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});


}
});






shmuel is a new contributor. Be nice, and check out our Code of Conduct.










draft saved

draft discarded


















StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3053247%2fterm-for-concrete-category-with-initial-morphism-for-each-element%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown

























1 Answer
1






active

oldest

votes








1 Answer
1






active

oldest

votes









active

oldest

votes






active

oldest

votes









6














If what you're after is a concrete category where $U$ is representable, then such categories are called representably concrete.






share|cite|improve this answer





















  • What I was looking for is probably the term generator (or separator.), but the definitions in ncatlab.org/nlab/show/separator and en.wikipedia.org/wiki/Generator_(category_theory) don't match. I need the term as defined in Wiki. Also, is there a term for a category with a generator?
    – shmuel
    Dec 26 '18 at 21:23










  • @shmuel - Isn't the definition in one of those just the contrapositive of the other?
    – Malice Vidrine
    Dec 26 '18 at 22:28










  • No; the nlab definition doesn't require that there be arrows from the generator to every other object.
    – shmuel
    Dec 27 '18 at 20:19
















6














If what you're after is a concrete category where $U$ is representable, then such categories are called representably concrete.






share|cite|improve this answer





















  • What I was looking for is probably the term generator (or separator.), but the definitions in ncatlab.org/nlab/show/separator and en.wikipedia.org/wiki/Generator_(category_theory) don't match. I need the term as defined in Wiki. Also, is there a term for a category with a generator?
    – shmuel
    Dec 26 '18 at 21:23










  • @shmuel - Isn't the definition in one of those just the contrapositive of the other?
    – Malice Vidrine
    Dec 26 '18 at 22:28










  • No; the nlab definition doesn't require that there be arrows from the generator to every other object.
    – shmuel
    Dec 27 '18 at 20:19














6












6








6






If what you're after is a concrete category where $U$ is representable, then such categories are called representably concrete.






share|cite|improve this answer












If what you're after is a concrete category where $U$ is representable, then such categories are called representably concrete.







share|cite|improve this answer












share|cite|improve this answer



share|cite|improve this answer










answered Dec 26 '18 at 19:55









Ittay Weiss

63.6k6101183




63.6k6101183












  • What I was looking for is probably the term generator (or separator.), but the definitions in ncatlab.org/nlab/show/separator and en.wikipedia.org/wiki/Generator_(category_theory) don't match. I need the term as defined in Wiki. Also, is there a term for a category with a generator?
    – shmuel
    Dec 26 '18 at 21:23










  • @shmuel - Isn't the definition in one of those just the contrapositive of the other?
    – Malice Vidrine
    Dec 26 '18 at 22:28










  • No; the nlab definition doesn't require that there be arrows from the generator to every other object.
    – shmuel
    Dec 27 '18 at 20:19


















  • What I was looking for is probably the term generator (or separator.), but the definitions in ncatlab.org/nlab/show/separator and en.wikipedia.org/wiki/Generator_(category_theory) don't match. I need the term as defined in Wiki. Also, is there a term for a category with a generator?
    – shmuel
    Dec 26 '18 at 21:23










  • @shmuel - Isn't the definition in one of those just the contrapositive of the other?
    – Malice Vidrine
    Dec 26 '18 at 22:28










  • No; the nlab definition doesn't require that there be arrows from the generator to every other object.
    – shmuel
    Dec 27 '18 at 20:19
















What I was looking for is probably the term generator (or separator.), but the definitions in ncatlab.org/nlab/show/separator and en.wikipedia.org/wiki/Generator_(category_theory) don't match. I need the term as defined in Wiki. Also, is there a term for a category with a generator?
– shmuel
Dec 26 '18 at 21:23




What I was looking for is probably the term generator (or separator.), but the definitions in ncatlab.org/nlab/show/separator and en.wikipedia.org/wiki/Generator_(category_theory) don't match. I need the term as defined in Wiki. Also, is there a term for a category with a generator?
– shmuel
Dec 26 '18 at 21:23












@shmuel - Isn't the definition in one of those just the contrapositive of the other?
– Malice Vidrine
Dec 26 '18 at 22:28




@shmuel - Isn't the definition in one of those just the contrapositive of the other?
– Malice Vidrine
Dec 26 '18 at 22:28












No; the nlab definition doesn't require that there be arrows from the generator to every other object.
– shmuel
Dec 27 '18 at 20:19




No; the nlab definition doesn't require that there be arrows from the generator to every other object.
– shmuel
Dec 27 '18 at 20:19










shmuel is a new contributor. Be nice, and check out our Code of Conduct.










draft saved

draft discarded


















shmuel is a new contributor. Be nice, and check out our Code of Conduct.













shmuel is a new contributor. Be nice, and check out our Code of Conduct.












shmuel is a new contributor. Be nice, and check out our Code of Conduct.
















Thanks for contributing an answer to Mathematics Stack Exchange!


  • Please be sure to answer the question. Provide details and share your research!

But avoid



  • Asking for help, clarification, or responding to other answers.

  • Making statements based on opinion; back them up with references or personal experience.


Use MathJax to format equations. MathJax reference.


To learn more, see our tips on writing great answers.





Some of your past answers have not been well-received, and you're in danger of being blocked from answering.


Please pay close attention to the following guidance:


  • Please be sure to answer the question. Provide details and share your research!

But avoid



  • Asking for help, clarification, or responding to other answers.

  • Making statements based on opinion; back them up with references or personal experience.


To learn more, see our tips on writing great answers.




draft saved


draft discarded














StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3053247%2fterm-for-concrete-category-with-initial-morphism-for-each-element%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown





















































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown

































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown







Popular posts from this blog

Questions related to Moebius Transform of Characteristic Function of the Primes

List of scandals in India

Can not write log (Is /dev/pts mounted?) - openpty in Ubuntu-on-Windows?