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visits member for 4 years, 6 months
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Mar
31
reviewed Edit suggested edit on Is there a purely group-theoretic reformulation of an equivalence of subgroups?
Mar
31
revised Is there a purely group-theoretic reformulation of an equivalence of subgroups?
I've added a link to a video of a conference of M. Izumi on this subject.
Mar
31
comment Given a 2-category, is the hammock localization wrt the equivalences equivalent to taking the hom-wise nerve of the maximal subgroupoids?
@Zhen Lin : This helped me. Thanks again!
Mar
31
comment Given a 2-category, is the hammock localization wrt the equivalences equivalent to taking the hom-wise nerve of the maximal subgroupoids?
Thank you for this example! You are right that the hammock localization cannot distinguish different 2-isomorphisms. Now if the hom-categories are preorders, the answer could still be affirmative. Any thoughts on this?
Mar
30
asked Given a 2-category, is the hammock localization wrt the equivalences equivalent to taking the hom-wise nerve of the maximal subgroupoids?
Mar
30
awarded  Electorate
Mar
20
awarded  Custodian
Mar
20
reviewed Approve suggested edit on Order homomorphism functions on $\omega_1$
Mar
20
comment The most unexpected and/or the least natural category theory theorem?
But in order to get an interpretation of logic in an elementary topos you need to know that it has finite colimits, don't you?
Mar
16
awarded  Nice Question
Mar
16
comment Pseudonyms of famous mathematicians
According to that homepage Rhineghost was a group five people. Rhineghost wrote 58 reviews for math.sci.net - some of them about articles of his own members, see numbers 11 and 22 on the list of reviews
Mar
16
comment Pseudonyms of famous mathematicians
Y.T. Rhineghost has a great homepage: csupomona.edu/~hlord/geist
Mar
14
awarded  Populist
Mar
13
comment Sheaffication using a $\lambda$-transfinite colimit
I would love to do this. Maybe it works out some time...
Mar
12
answered Sheaffication using a $\lambda$-transfinite colimit
Feb
27
awarded  Custodian
Jan
25
awarded  Popular Question
Jan
23
awarded  Nice Answer
Jan
12
awarded  Revival
Jan
12
answered What is about J. v. Neumann's “Continuous geometry”?