Essentials of the Method of Maximal Singularities
نویسنده
چکیده
We start with a very brief description of the principal events in the history of our subject. About 1870 M.Noether discovered [N] that the group of birational automorphisms of the projective plane BirP, which is known also as the Cremona group CrP, is generated by its subgroup AutP = AutC/C and any quadratic Cremona transformation τ , which in a certain system of homogeneous coordinates can be written down as τ : (x0: x1: x2) → (x1x2: x0x2: x0x1). Noether’s arguments were as follows. Take any Cremona transformation
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