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## gbvy[W > ߋ̃Z~i[ > 2011Nx㐔wZ~i[

### 2011Nx

(9)
@ : 24 N2 3 () 15:00 --
@ : Lww B701
u : ߐ{Oa iCwj
^Cg : RPDl̏̋Ȑ̕ό`Qɂ
AuXgNgFMumford3ˉeԓً̔ȐHilbertXL[
IɔłȂ(generically non-reduced)񐬕Ƃ.
䎁Ƃ̋ł͂̔񐬕ʉ, ͊ȈՉ邱
ɂ, ̒PD3ˉel̂ɑ΂, ً̏̔Ȑ
HilbertXL[IɔłȂ񐬕Ƃ.
܂̒, 3l̏̋Ȑɑ΂, Ȑ1ʖό`
Q󂯂ׂ̏\ꂽ. {uł͂̌ʂɂďЉ
Ƌ, 4ȏ̑l̏̋Ȑ̔Qό`̗ɂĂ
Љ.

(8)
@ : 24 N1 27 () 15:00 --
@ : Lww B701
u : Lcl @(w)
^CgFK3ȉ~ȖʂMordell-WeilQ̐ɂ
AuXgNgFʂK3ȉ~Ȗʂ̓Iɗ^ꂽ
AMordell-WeilQ̐肷邱Ƃ͗eՂł͂
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mĂA͂납18̓ƗȌ猩
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ł炭ł낤Ǝv̂邱Ƃ
̂ł񍐂B܂AK3ȉ~ȖʂMordell-Weil
QƂ̌Ɋւʘ_̊T͂߁Ȃȉ~Ȗ
̓Mordell-WeilQ߂ۂ̖_ɂďqׂB

(7)
@ : 23 N12 16 () 15:00 --
@ : Lww B701
u : R Y (kw)
@ : p-i_Ɛ_

(6) ( 2 u܂. jEԂiƈقȂ̂łӂ.)
@ : 23 N11 21 () 13:00 -- 16:30
@ : Lww B701
u : Timothy Logvinenko (the University of Warwick)
u@1 : 13:00 -- 14:30
@1 : Derived Reid's recipe for threefold singularities
AugNg1 : The classical McKay correspondence matches the irreducible
representations of finite G \subset SL_2(C) with
the irreducible exceptional curves on the minimal resolution
Y of C^2/G. This correspondence was realised as a natural
K-theory isomorphism by Gonzales-Sprinberg and Verdier, and
then generalised to the famous derived category equivalence
by Bridgeland, King and Reid (BKR), which holds for all
finite subgroups G of SL_3(C), as well as SL_2(C).
I explain how we can extract from BKR equivalence
a more geometrical correspondence which we call "derived
Reid's recipe": to every representation of G it assigns
a subvariety of the exceptional set of Y. In dimension 2
this gives precisely the classical McKay correspondence.
In dimension 3, this gives a new, previously unknown
correspondence. For an abelian G we prove it to be governed
completely by an old toric geometry calculation known as
"Reid's recipe".

u@2 : 15:00 -- 16:30
@2 : Relative spherical objects
"Seidel and Thomas introduced some years ago a notion
of a spherical object in the derived category D(X) of
a smooth projective variety X. Such objects induce,
in a simple way, auto-equivalences of D(X) called
'spherical twists'. In a sense, they are mirror-symmetric
analogues of Lagrangian spheres on a symplectic manifold and
the induced auto-equivalences mirror the Dehn twists
associated with the latter.
We generalise this notion to the relative context by
explaining what does it mean for an object of D(Z x X)
to be spherical _over Z_ for any two separated schemes
Z and X of finite type. Such objects induce naturally two
auto-equivalences: one of D(X), called "the twist", and
the other of D(Z) called "the co-twist". For objects
of D(Z x X) which are orthogonal over Z we give a simple
cohomological criterion for being spherical over Z which
resembles the original definition of Seidel and Thomas.
This is a joint work with Rina Anno (UMass/Amherst).

(5)
@ : 23 N 6 3 () 15:00 -- 16:30
@ : Lww B701
u : Y [ ({w)
@ : L̏̑㐔ȐƃyAOÍ
AuXgNg : 1999N-2001Nɂēĉ̎OJőŃFCyAO
pVÍ(yAOÍ)ĂǍ̏\NԂ
͓IɌi߂ĂByAOÍł́Aɑȉ~Ȑ
ȉ~Ȑ̃Rrl̏̃FCyAOg邪AÍ
\ɗpȉ~Ȑ⒴ȉ~Ȑׂ̖́Aȉ~ȐÍ
ȉ~ȐÍ\ۂ̏GɂȂB
{uł́AyAOÍ̎dg݂ɂĂ̊Tn߁A
ƂɁAyAOÍ̍\ɕKvȏ𖞂L̏̑ȉ~Ȑ
⒴ȉ~Ȑ悭@ɂāȀ\NԂ̐iW󋵂ЉB

(4)
@ : 23 N 5 20 () 15:00 -- 16:30
@ : Lww B701
u : ؑ r (Lw)
@ : Diophantine Frobenius Problem

(3)
@ : 23 N 5 13 () 15:00 -- 16:30
@ : Lww B701
u : V rY (Lw)
@ : -categories for the working mathematician
AuXgNgFJacob Lurie ͔ނ D _̈ꕔł
``Higher Topos Theory'' (925y[W) ɉ Joyal (=quasi-category)
̗_OIɊg[ SGA4 Grothendieck g|X_ɈʉB
Grothendieck ʑԂł͂Ȃg|XpČ_bɂđ㐔􉽂n߂悤ɁA
pu㐔􉽁v̔W܂ĂB
͓ɁuƂ͉vɏœ_iĉB

(2)
@ : 23 N 4 22 () 16:30 -- 18:00
@ : Lww B701
u : s Ďj (sww)
@ : \_Ɛ_Isϗ
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_Isϗʂƌт𒲂ׂ鎖͋[.
̎`̏ꍇɉ.

(1)
@ : 23 N 4 22 () 14:45 -- 16:15
@ : Lww B701
u : Rc Iq (Rȑwwpw)
@ : Ȗʏ̈xNg̃WC̑oLI
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