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TheCatsters
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TheCatsters
Style: Educational
Joined: September 13, 2007
Last Sign In: 1 week ago
Videos Watched: 977
Subscribers: 639
Channel Views: 39,525
Videos on various topics in category theory.

These are probably best viewed in full-screen mode.
Country: United Kingdom
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Recent Activity  
TheCatsters uploaded a new video (4 months ago)
Statement of Yoneda lemma and explanation of "why" it is true
 
 
TheCatsters uploaded a new video (4 months ago)
Further explanation of the Yoneda embedding (including calling it that, ...   more
 
 
TheCatsters uploaded a new video (4 months ago)
Definition of representable functors and the Yoneda embedding (though wi...   more
 
 
TheCatsters uploaded a new video (7 months ago)
Definition of comma categories D over and under F for a functor F, and F...   more
 
 
TheCatsters uploaded a new video (8 months ago)
Definition of slice categories C/X and X/C, products in C/X as pullbacks...   more
 
Channel Comments (18)
akhcarubehc (3 months ago)
Yes, please, for people without background, a suggestion of order would be helpful.
sigfpe (4 months ago)
Here's my request list:

Dinatural transformations
Ends
Coends
Kan Extensions
All of the above done with string diagrams
TheCatsters (4 months ago)
henrylaxen, there is no order. There are many people with different backgrounds tuning in, so it is difficult to be prescriptive. We certainly do not have any order in mind. However, if anyone out there has suggestions for an ordering, do let us know.
henrylaxen (4 months ago)
Dear Catsters,
Now that there are over 70 videos, is there any chance of you posting some kind of order in which we should watch them if we want to start at the beginning and proceed in a logical sequence. youtube only gives approximate dates (1 year ago) which isn't very helpful in determining an order. Thanks.
Henry Laxen
stubbedtoe9 (5 months ago)
I'm just getting comfortable with the language of category theory, so I guess I'll have to come back to these videos later. It seems like you start about 30 minutes ahead of where I am (measured in your lecture time).

I look forward to watching these. Thanks for your work.
aurinkona (6 months ago)
yes, i agree with philippechaput: a lecture or two on the Yoneda lemma would be awesome!
grokodile (6 months ago)
love your stuff, thanks. I don't suppose you know anything about toposes (topoi) that you'd like to share?
shadowsc15 (7 months ago)
\o/ hooray for you!
simonterrington (7 months ago)
Thank you so much for doing this guys. It's really well explained and very helpful
Shindashi (8 months ago)
All Hail.
Your style and content are truly mouthwatering.
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Playlists
Adjunctions
7 videos
Adjunctions 7 Videos
Some videos introducting adjunctions and their relationship to monads.
String diagrams, adjunctions and monads
5 videos
String diagrams for functors and natural transformations are introduced, then we show how adjunctions and monads have a very simple and natural description in this language.
Limits and colimits
13 videos
Limits and colimits, starting with specific examples of common (co)limits that have special names, then formal definition of limit and colimit over an arbitrary diagram. Universal properties.
Representables and Yoneda 3
8:18
Statement of Yoneda lemma and explanation of "why" it is true
4 months ago 684 views TheCatsters
Representables and Yoneda 2
8:07
Further explanation of the Yoneda embedding (including calling it that, but not ye...
4 months ago 284 views TheCatsters
Representables and Yoneda 1
9:52
Definition of representable functors and the Yoneda embedding (though without call...
4 months ago 537 views TheCatsters
Slice and comma categories 2
9:16
Definition of comma categories D over and under F for a functor F, and F over and ...
7 months ago 713 views TheCatsters
Slice and comma categories 1
9:43
Definition of slice categories C/X and X/C, products in C/X as pullbacks in C
8 months ago 730 views TheCatsters
Coequalisers 2
7:47
[TRANSLATED] Coequalisers 2
[TRANSLATED] Coequalisers 2
Quotient groups as coequalisers in the category of groups
9 months ago 286 views TheCatsters
Coequalisers 1
8:26
[TRANSLATED] Coequalisers 1
[TRANSLATED] Coequalisers 1
Definition of coequaliser, examples in Set: coequalisers can be constructed as equ...
9 months ago 410 views TheCatsters
Adjunctions from morphisms 5
9:23
Description of the left adjoint to the pull-back
9 months ago 268 views TheCatsters
Adjunctions from morphisms 4
9:14
A proof that the push-forward is right adjont to pull-back.
9 months ago 237 views TheCatsters