Blogs about: Ag Foundations
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Residue field does not change under restriction to closed subschemes or fibres
It does not change when restricting to closed subschemes. It is because the residue ring does not change : . When taking fibre of a morphism : , Consider a scheme Spec . Then by the universal property… more →
Dung Hoang Nguyen's Weblog
Residue field does not change under restriction to closed subschemes or fibres
wrote 1 year ago: It does not change when restricting to closed subschemes. It is because the residue ring does not ch … more →
Flat map - fibre dimension
wrote 1 year ago: Flat map has a nice property : the fibre dimension is very well behaved. Assume we have a flat map . … more →
Blow-up of morphisms
wrote 1 year ago: Suppose we have a morphism . Let’s say we are going to blow up along a coherent sheaf of ideal … more →
Inverse image ideal sheaf, blow-up, and exceptional divisor
wrote 1 year ago: If we have morphism , and a sheaf of ideal on , then the inverse image sheaf is therefore a subsheaf … more →
Normal Cone
wrote 1 year ago: If is a closed subscheme of , with the defining sheaf of ideals, then the normal cone to in is defin … more →
Vector bundle and its sheaf of sections
wrote 1 year ago: A vector bundle over a scheme is a scheme with a projection map in which locally is has the form , i … more →
Projective completion of a cone over a scheme
wrote 1 year ago: A cone over a scheme is the Spec of the sheaf of graded - algebra , is generated by as an algebra. T … more →
