550 Vaughan Jones, 

   550 Vaughan Jones, 

   551 Chris Schommer-Pries, 

   551 Chris Schommer-Pries, 

   552 Thomas Tradler,

   552 Thomas Tradler,

   553 Kevin Costello, 

   553 Kevin Costello, 

   554 Chris Douglas,

   554 Chris Douglas,

   555 and

   556 and

   557 for many interesting and useful conversations. 

   558 for many interesting and useful conversations. 

   558 Peter Teichner ran a reading course based on an earlier draft of this paper, and the detailed feedback

   559 Peter Teichner ran a reading course based on an earlier draft of this paper, and the detailed feedback

   559 we got from the student lecturers lead to very many improvements in later drafts.

   560 we got from the student lecturers lead to very many improvements in later drafts.

   560 So big thanks to

   561 So big thanks to

   561 Aaron Mazel-Gee,

   562 Aaron Mazel-Gee,