## 112.7 Deformation theory à la Schlessinger

We have a chapter on this material, see Formal Deformation Theory, Section 89.1. We have a chapter discussing examples of the general theory, see Deformation Problems, Section 92.1. We have a chapter, see Deformation Theory, Section 90.1 which discusses deformations of rings (and modules), deformations of ringed spaces (and sheaves of modules), deformations of ringed topoi (and sheaves of modules). In this chapter we use the naive cotangent complex to describe obstructions, first order deformations, and infinitesimal automorphisms. This material has found some applications to algebraicity of moduli stacks in later chapters. There is also a chapter discussing the full cotangent complex, see Cotangent, Section 91.1.

Comment #196 by Emmanuel Kowalski on

Pedantically speaking, "a la Schlessinger" should be "?96?a la Schlessinger"...

Comment #197 by Emmanuel Kowalski on

(and a backslash got skipped in the comment... ("à la Schlessinger")

Comment #198 by on

I notice that there is a character encoding issue. I will look into this.

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