# Start a new discussion

## Not signed in

Want to take part in these discussions? Sign in if you have an account, or apply for one below

## Discussion Tag Cloud

Vanilla 1.1.10 is a product of Lussumo. More Information: Documentation, Community Support.

• CommentRowNumber1.
• CommentAuthorUrs
• CommentTimeMay 30th 2013

I am starting an entry Poincaré duality algebra, but it still needs some attention

• CommentRowNumber2.
• CommentAuthorjim_stasheff
• CommentTimeMay 30th 2013
surely there are many other Poincaré duality algebras

jim
• CommentRowNumber3.
• CommentAuthorUrs
• CommentTimeMay 30th 2013

• CommentRowNumber4.
• CommentAuthorUrs
• CommentTimeJul 7th 2013
• (edited Jul 7th 2013)

• two more references on the $C^\ast$-case;

• remarks highlighting that the $C^\ast$-case is about duality in K-theory as opposed to in ordinary cohomology;

• a remark that for twisted groupoid convolution algebras the fact that the Poincaré duality is to the opposite algebra corresponds to keeping the same groupoid (up to equivalence) but inverting the twist

(this is no hard to see, but if anyone knows a place where this is remarked in the literature, I’d be grateful for a pointer.)

• CommentRowNumber5.
• CommentAuthorUrs
• CommentTimeJul 8th 2013

I have added at K-orientation and Umkehr maps discussion of push-forward in twisted K-theory.

Essentially the same discussion I have (with slight editorial changes) also copied to

Also added more related references to all these entries.

• CommentRowNumber6.
• CommentAuthorUrs
• CommentTimeJul 16th 2013

related discussion on MO here