Thursday, December 30, 2010

Definitions for CM, etc

CM ring - CM
CM-mod over local ring - Regular Seq.
Regular local ring - Reg. Seq.

Sunday, December 26, 2010

Thursday, December 16, 2010

Monday, December 13, 2010

Sunday, December 12, 2010

Injective module redux

Restriction & extension of scalars

Projectivity of module M and Ext^1(M,N)=0 for all f.g. N

Ext,Tor, pd, id

Also Eisenbud's projective characterization from appendix

simple module

Injective modules

Jordan-Holder

Isomorphic to R/m (NC-III, Jacobson)

Saturday, December 11, 2010

Friday, December 10, 2010

Thursday, December 9, 2010

Tuesday, December 7, 2010

Filtration of modules, support, Ass

Ext, Tor, pd, id

Also Ass(Redux)

Monday, November 29, 2010

Wednesday, November 24, 2010

Tuesday, November 23, 2010

gcd, lcm

Matsumura book, p.164,
Res(new)-M

UFD iff every prime of height 1 is principal, ACCPI, properties of principal primes

Eisenbud, Ex.3.11 (Old)
DVR & Dedekind Folder (New)

Monday, November 22, 2010

Saturday, November 20, 2010

Wednesday, November 17, 2010

n-th syzygy of projective resolution being projective

Ext,Tor,pd,id

Cor. f.g. proj. module over a Noetherian ring which has a finite proj. dim has a finite proj res. consisting of f.g. projective modules. -- UFD, c.i.

Tuesday, November 16, 2010

Monday, November 15, 2010

Sunday, November 7, 2010

Equivalence of categories (II)

C(Affine Varieties) = C(f.g.k-algebraic domains) = C(integral affine schemes over Spec k)

The last part is a conjecture.

Wednesday, November 3, 2010

Sunday, October 17, 2010

Saturday, October 16, 2010

Hom(A,G(X)) <-> Hom(X,SpecA)

Sch.5

α: X -> t(X)

continuity, dense image, homeo onto image... : Scheme II

Friday, October 15, 2010

Tuesday, September 21, 2010

Localizing graded ring, 1-1 correspondence of primes

Proj (P.P.)

Graded associated primes

Modules & Rings: Proj(P.P.) folder

Graded by Monoid: Ezra (Rs.)

Tuesday, August 31, 2010

McCoy's Rank

Atiyah soln project 2.11

Saturday, August 21, 2010

Wednesday, August 18, 2010

Hom commuting with tensor

Hom(M,N)*B=Hom(M_B,N_B) was first proved in Free,...

It was then used in Regular Sequences to prove Ext and Tor versions.

It was proved again in Extensions along with naturalness.

Hom_B(M*N,P)=Hom_A(M,Hom_B(N,P)) was first proved in Extensions in the context of bimodule theory, but (not its naturalness). It will be proved again in Bruns, along with naturalness in bimodule theory.

Edit: naturalness seems to be proved in Extension, not in Bruns.

Sunday, August 15, 2010