In mathematics, the Bernstein-Gelfand-Gelfand correspondence or BGG correspondence for short is the first example of the
Koszul duality In mathematics, Koszul duality, named after the French mathematician Jean-Louis Koszul, is any of various kinds of dualities found in representation theory of Lie algebras, abstract algebras (semisimple algebra) and topology (e.g., equivariant cohom ...
.
Established by
Joseph Bernstein
Joseph Bernstein (sometimes spelled I. N. Bernshtein; ; ; born 18 April 1945) is a Soviet-born Israeli mathematician working at Tel Aviv University. He works in algebraic geometry, representation theory, and number theory.
Biography
Bernstein ...
,
Israel Gelfand
Israel Moiseevich Gelfand, also written Israïl Moyseyovich Gel'fand, or Izrail M. Gelfand (, , ; – 5 October 2009) was a prominent Soviet and American mathematician, one of the greatest mathematicians of the 20th century, biologist, teache ...
, and Sergei Gelfand, the correspondence is an explicit triangulated equivalence that relates the bounded
derived category
In mathematics, the derived category ''D''(''A'') of an abelian category ''A'' is a construction of homological algebra introduced to refine and in a certain sense to simplify the theory of derived functors defined on ''A''. The construction pr ...
of
coherent sheaves
In mathematics, especially in algebraic geometry and the theory of complex manifolds, coherent sheaves are a class of sheaves closely linked to the geometric properties of the underlying space. The definition of coherent sheaves is made with refer ...
on the projective space
and the
stable category of graded modules
over the
exterior algebra
In mathematics, the exterior algebra or Grassmann algebra of a vector space V is an associative algebra that contains V, which has a product, called exterior product or wedge product and denoted with \wedge, such that v\wedge v=0 for every vector ...
; i.e.,
:
.
In the noncommutative setting, Martínez Villa and Saorín generalized the BGG correspondence to finite-dimensional
self-injective Koszul algebras with
coherent
Coherence is, in general, a state or situation in which all the parts or ideas fit together well so that they form a united whole.
More specifically, coherence, coherency, or coherent may refer to the following:
Physics
* Coherence (physics ...
Koszul duals
.
Roughly speaking, they proved that the stable category of finite-dimensional graded modules over a finite-dimensional self-injective Koszul algebra
is triangulated equivalent to the bounded derived category of the tails category of the Koszul dual
(when
is coherent).
References
Further reading
* Peter Jørgensen, A noncommutative BGG correspondence, February 2005, Pacific Journal of Mathematics 218(2):357-377, DOI:10.2140/pjm.2005.218.357
* http://pantodon.jp/index.rb?body=Koszul_duality in Japanese
* https://www.mathsoc.jp/section/algebra/algsymp_past/algsymp13_files/yamaura.pdf in Japanese
Algebraic geometry
{{algebraic-geometry-stub