Singularities in characteristic 0 and characteristic p
نویسنده
چکیده
1 Characteristic 0 We start with a basic question: given a polynomial f ∈ C[z1, · · · , zn] with a singularity at 0, how can we measure the “singularness” of this polynomial in a precise way? In other words: we can look at various singularities and see intuitively that some singularities are worse than others. For instance, it feels like a transverse self-intersection is probably not as bad as a cusp. And a sharper cusp feels more singular than a rather gradual cusp:
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