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Lee Mosher
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I will answer the question of whether this also gives the classification cheaply.

No.

It gives the classification at the expense of proving that every surface group has a free cocompact action on the upper half plane (or on the euclidean plane, or on the 2-sphere). This in turn depends upon proving:

  • Every surface has a triangulation (Rado's Theorem, and now you've done 90% of the work of the classification theorem)...

  • Every triangulated surface has a compatible smooth structure...

  • Every smooth surface has a compatible conformal structure...

and, finally

  • Every conformal structure has a compatible hyperbolic metric, euclidean metric, or spherical metric (the uniformization theorem).

I will answer the question of whether this also gives the classification cheaply.

No.

It gives the classification at the expense of proving that every surface group has a free cocompact action on the upper half plane. This in turn depends upon proving:

  • Every surface has a triangulation (Rado's Theorem, and now you've done 90% of the work of the classification theorem)...

  • Every triangulated surface has a compatible smooth structure...

  • Every smooth surface has a compatible conformal structure...

and, finally

  • Every conformal structure has a compatible hyperbolic metric (the uniformization theorem).

I will answer the question of whether this also gives the classification cheaply.

No.

It gives the classification at the expense of proving that every surface group has a free cocompact action on the upper half plane (or on the euclidean plane, or on the 2-sphere). This in turn depends upon proving:

  • Every surface has a triangulation (Rado's Theorem, and now you've done 90% of the work of the classification theorem)...

  • Every triangulated surface has a compatible smooth structure...

  • Every smooth surface has a compatible conformal structure...

and, finally

  • Every conformal structure has a compatible hyperbolic metric, euclidean metric, or spherical metric (the uniformization theorem).
Source Link
Lee Mosher
  • 15.4k
  • 2
  • 42
  • 81

I will answer the question of whether this also gives the classification cheaply.

No.

It gives the classification at the expense of proving that every surface group has a free cocompact action on the upper half plane. This in turn depends upon proving:

  • Every surface has a triangulation (Rado's Theorem, and now you've done 90% of the work of the classification theorem)...

  • Every triangulated surface has a compatible smooth structure...

  • Every smooth surface has a compatible conformal structure...

and, finally

  • Every conformal structure has a compatible hyperbolic metric (the uniformization theorem).