nLab
resolution of singularities

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Idea

Given a space XX of sorts, in particular a scheme or variety, with singularities, i.e. with a subspace SXS \subset X at which the geometry is non-regular (specifically: not smooth), a resolution of the singularity is a suitable regular (non-singular) space X^\widehat X equipped with a morphism back to the original space

p:X^X p \;\colon\; \widehat X \longrightarrow X

which is an isomorphism away from the singular locus.

Typical resolution of singularities is by “blow-up” of the singularity where the singular point is replaced by an n-sphere, then called the “exceptional divisor” of the blow-up.

(quick review of the basic details includes Berghoff 14, section 4.1)

Examples

References

The existence of resolutions of singularities by “blow-up” was established, for ground fields of characteristic zero, in some generality in

  • Heisuke Hironaka, Resolution of Singularities of an Algebraic Variety Over a Field of Characteristic Zero: I, Annals of Mathematics Second Series, Vol. 79, No. 1 (Jan., 1964), pp. 109-203 (95 pages) (jstor:1970486)

Basic review includes

The theorem of Hironaka 64 was used to discuss singular distributions (in the sense of generalized functions) in

This method is closely related to the resolution of singularities of propagators/Feynman amplitudes by passage to compactified configuration spaces of points, as disucussed at Feynman amplitudes on compactified configuration spaces of points.

See also

Last revised on November 5, 2018 at 09:26:50. See the history of this page for a list of all contributions to it.