inclusion functor of FinSet into Top












3














I was reading Codensity and Stone spaces by Andrei Sipos where the author defines an inclusion functor from FinSet to Top without (or perhaps I missed it) specifying the topological structure we would endow on finite sets. Does any one know if there is a canonical choice of topological structure associated with a given finite set?










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  • 5




    The discrete topology is standard. It's the only Hausdorff one, at least.
    – anomaly
    Nov 20 '18 at 20:52










  • Probably the discrete topology, but I can't say for sure
    – Max
    Nov 20 '18 at 20:53






  • 1




    @anomaly thanks! The observation that only the discrete topology is helpful! Since the claim is the algebra category associated with the induced codensity monad given by the inclusion functor from FinSet into Top is the category of Stone spaces, the Hausdorff structure is probably necessary.
    – discretizer
    Nov 20 '18 at 21:01










  • @Max thanks a lot!
    – discretizer
    Nov 20 '18 at 21:02
















3














I was reading Codensity and Stone spaces by Andrei Sipos where the author defines an inclusion functor from FinSet to Top without (or perhaps I missed it) specifying the topological structure we would endow on finite sets. Does any one know if there is a canonical choice of topological structure associated with a given finite set?










share|cite|improve this question




















  • 5




    The discrete topology is standard. It's the only Hausdorff one, at least.
    – anomaly
    Nov 20 '18 at 20:52










  • Probably the discrete topology, but I can't say for sure
    – Max
    Nov 20 '18 at 20:53






  • 1




    @anomaly thanks! The observation that only the discrete topology is helpful! Since the claim is the algebra category associated with the induced codensity monad given by the inclusion functor from FinSet into Top is the category of Stone spaces, the Hausdorff structure is probably necessary.
    – discretizer
    Nov 20 '18 at 21:01










  • @Max thanks a lot!
    – discretizer
    Nov 20 '18 at 21:02














3












3








3







I was reading Codensity and Stone spaces by Andrei Sipos where the author defines an inclusion functor from FinSet to Top without (or perhaps I missed it) specifying the topological structure we would endow on finite sets. Does any one know if there is a canonical choice of topological structure associated with a given finite set?










share|cite|improve this question















I was reading Codensity and Stone spaces by Andrei Sipos where the author defines an inclusion functor from FinSet to Top without (or perhaps I missed it) specifying the topological structure we would endow on finite sets. Does any one know if there is a canonical choice of topological structure associated with a given finite set?







category-theory






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share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Nov 20 '18 at 21:03









Derek Elkins

16.2k11337




16.2k11337










asked Nov 20 '18 at 20:48









discretizer

1377




1377








  • 5




    The discrete topology is standard. It's the only Hausdorff one, at least.
    – anomaly
    Nov 20 '18 at 20:52










  • Probably the discrete topology, but I can't say for sure
    – Max
    Nov 20 '18 at 20:53






  • 1




    @anomaly thanks! The observation that only the discrete topology is helpful! Since the claim is the algebra category associated with the induced codensity monad given by the inclusion functor from FinSet into Top is the category of Stone spaces, the Hausdorff structure is probably necessary.
    – discretizer
    Nov 20 '18 at 21:01










  • @Max thanks a lot!
    – discretizer
    Nov 20 '18 at 21:02














  • 5




    The discrete topology is standard. It's the only Hausdorff one, at least.
    – anomaly
    Nov 20 '18 at 20:52










  • Probably the discrete topology, but I can't say for sure
    – Max
    Nov 20 '18 at 20:53






  • 1




    @anomaly thanks! The observation that only the discrete topology is helpful! Since the claim is the algebra category associated with the induced codensity monad given by the inclusion functor from FinSet into Top is the category of Stone spaces, the Hausdorff structure is probably necessary.
    – discretizer
    Nov 20 '18 at 21:01










  • @Max thanks a lot!
    – discretizer
    Nov 20 '18 at 21:02








5




5




The discrete topology is standard. It's the only Hausdorff one, at least.
– anomaly
Nov 20 '18 at 20:52




The discrete topology is standard. It's the only Hausdorff one, at least.
– anomaly
Nov 20 '18 at 20:52












Probably the discrete topology, but I can't say for sure
– Max
Nov 20 '18 at 20:53




Probably the discrete topology, but I can't say for sure
– Max
Nov 20 '18 at 20:53




1




1




@anomaly thanks! The observation that only the discrete topology is helpful! Since the claim is the algebra category associated with the induced codensity monad given by the inclusion functor from FinSet into Top is the category of Stone spaces, the Hausdorff structure is probably necessary.
– discretizer
Nov 20 '18 at 21:01




@anomaly thanks! The observation that only the discrete topology is helpful! Since the claim is the algebra category associated with the induced codensity monad given by the inclusion functor from FinSet into Top is the category of Stone spaces, the Hausdorff structure is probably necessary.
– discretizer
Nov 20 '18 at 21:01












@Max thanks a lot!
– discretizer
Nov 20 '18 at 21:02




@Max thanks a lot!
– discretizer
Nov 20 '18 at 21:02










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