When are induction and conduction functors isomorphic ?

نویسندگان

  • Claudia Menini
  • Constantin Nastasescu
چکیده

Let R = ⊕ g∈GRg be a G-graded ring. It is well known (see e.g. [D], [M1], [N], [NRV], [NV]) that in the study of the connections that may be established between the categories R-gr of graded R-modules and R1-mod (1 is the unit element of G), an important role is played by the following system of functors : (−)1 : R-gr → R1-mod given by M 7→ M1, where M = ⊕ g∈GMg is a graded left R-module, the induced functor, Ind : R1-mod→ R-gr, which is defined as follows : if N ∈ R1mod, then Ind(N) = R⊗R1N which has the G-grading given by (R ⊗R1 N)g = Rg ⊗R1 N, ∀g ∈ G, and the coinduced functor, Coind : R1-mod→ R-gr, which is defined in the following way : if N ∈ R1-mod, then Coind(N) = ⊕ g∈GCoind(N)g , where Coind(N)g = {f ∈ HomR1(R1RR, N) | f(Rh) = 0, ∀ h 6= g−1} .

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Comparison of spectral sequences involving bifunctors

Suppose given functors A × A F B G C between abelian categories, an object X in A and an object X ′ in A such that F (X,−), F (−,X ) and G are left exact, and such that further conditions hold. We show that, E1-terms exempt, the Grothendieck spectral sequence of the composition of F (X,−) and G evaluated at X ′ is isomorphic to the Grothendieck spectral sequence of the composition of F (−,X ) a...

متن کامل

The Bicategory of Corings

To a B-coring and a (B, A)-bimodule that is finitely generated and projective as a right A-module an A-coring is associated. This new coring is termed a base ring extension of a coring by a module. We study how the properties of a bimodule such as separability and the Frobenius properties are reflected in the induced base ring extension coring. Any bimodule that is finitely generated and projec...

متن کامل

Crystals of Fock Spaces and Cyclotomic Rational Double Affine Hecke Algebras

We define the i-restriction and i-induction functors on the category O of the cyclotomic rational double affine Hecke algebras. This yields a crystal on the set of isomorphism classes of simple modules, which is isomorphic to the crystal of a Fock space.

متن کامل

Monodromy of Partial Kz Functors for Rational Cherednik Algebras

1.1. Shan has proved that the categories Oc(Wn) for rational Cherednik algebras of type Wn = W (G(`, 1, n)) = Snn(μ`) with n varying, together with decompositions of the parabolic induction and restriction functors of Bezrukavnikov-Etingof, provide a categorification of an integrable s̃le Fock space representation F(m), [18]. The parameters m ∈ Z` and e ∈ N ∪ {∞} arise from the choice of paramet...

متن کامل

Implications of Yoneda Lemma to Category Theory

This is a survey paper on the implication of Yoneda lemma, named after Japanese mathematician Nobuo Yoneda, to category theory. We prove Yoneda lemma. We use Yoneda lemma to prove that each of the notions universal morphism, universal element, and representable functor subsumes the other two. We prove that a category is anti-equivalent to the category of its representable functors as a corollar...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2000