#12892: Toric fibration morphisms
--------------------------------------+-------------------------------------
Reporter: vbraun | Owner: AlexGhitza
Type: enhancement | Status: needs_work
Priority: major | Milestone: sage-5.3
Component: algebraic geometry | Resolution:
Keywords: sd40.5 | Work issues: comments and rebasing
Report Upstream: N/A | Reviewers: Andrey Novoseltsev
Authors: Volker Braun | Merged in:
Dependencies: #12361, #13023 | Stopgaps:
--------------------------------------+-------------------------------------
Comment (by novoselt):
Replying to [comment:19 vbraun]:
> It seems like there is a natural way to factor a morphism into a
surjection and an injection, first map to the image fan and then embed the
image in the codomain.
That's what you have suggested earlier and this is also the factorization
used in HLY paper. The intermediate variety is clearly defined: intersect
the codomain fan with the linear subspace spanned by the map of lattices.
Works fine when both fans of domain/codomain are complete.
Now for the blowup chart you propose to replace a map between two affine
varieties induced by the identity matrix with a reverse factorization -
first inclusion, then surjection, going through an intermediate non-affine
variety. How is this intermediate variety defined/constructed in general?
--
Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/12892#comment:25>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica,
and MATLAB
--
You received this message because you are subscribed to the Google Groups
"sage-trac" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/sage-trac?hl=en.
